# When is room treatment needed



## marty1

My room is bare wall apart from blackout curtains almost all the way along 1 side of the room where the windows are. The walls are plasterboard with brick underneath (I think :scratch. The ceiling is plasterboard and the floor is carpeted.

I do have slap echo in the room but in general I love the sound from my system. So how do I know whether it will be worth putting accoustic panels and bass traps up?

Do I just put a couple of panels up at the first reflection point and that is it, just enough to maybe get rid of the slap echo, or do I go for broke and put bass traps in the 4 corners of the room, absorbant panels around the front 3rd of the room, absorb/diffuse combi panels along the bare side wall and diffusers on the rear wall and diffusers on the ceiling.

In general do you just treat where necessary or can you fill the room with treatment like I suggested above and assume that would give you the best balance of sound overall. I like to keep things as simple as possible (so my simple brain can deal with things better :rolleyesno so I would prefer, if possible, a straight instruction as opposed to, put one panel up see how that sounds, put another one up, see how that sounds etc etc.

I am on a tight budget so I would rather know exactly what I need to put up, if I even need to put any up at all. I have spent a lot of time with REW trying to get the best out my sub, I found that quite a draining process so if there is simple way of achieving good quality sound that I will notice a big difference from the good sound I am hearing now, without measuring all the time that would be great.

I would really appreciate your advice :help:

Kind Regards
Marty


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## grn1969c10

> I would prefer, if possible, a straight instruction as opposed to, put one panel up see how that sounds


You may get generalized advice on which type of room treatments can help with the echo, but I don't expect you to get the specific answer you want with so little information given. Room treatments vary considerably based on the frequency range of the problem you wish to correct. You could examine the waterfall graphs you have and determine which frequencies have the biggest decay problems. 

I don't have personal experience solving that particular problem, but I'm guessing it involves the higher frequencies well above the sub range and will require broadband treatments. knowing if you are using a measurement microphone or a sound level meter to obtain measurements would indicate how useful your full range measurements could be. Since your room is apparently non-symmetrical, you might consider posting a layout drawing with measurements so people have an idea on what your dealing with. An acceptable budget and WAF factors which must be adhered to might help people give you more helpful suggestions as well.

Matt


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## marty1

I have put a 360 of my room although the rear bipole speakers behind the couch are now further apart and closer to the corners:


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## bpape

Broadband bass absorption floor to ceiling in the 2 front corners. I'd also do some in the shorter left rear corner.

I would add at least 2-3 2" 2'x4' absorption panels on the left wall to bring better left to right symmetry by matching better with the curtains on the other side.

Ideally, the front wall would also be 100% dead to help with boundary interactions and to prevent reflections from the surround channels contaminating the front soundstage.

Bryan


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## marty1

bpape said:


> Broadband bass absorption floor to ceiling in the 2 front corners. I'd also do some in the shorter left rear corner.
> 
> I would add at least 2-3 2" 2'x4' absorption panels on the left wall to bring better left to right symmetry by matching better with the curtains on the other side.
> 
> Ideally, the front wall would also be 100% dead to help with boundary interactions and to prevent reflections from the surround channels contaminating the front soundstage.
> 
> Bryan


So do you mean put absorbant panels all around the screen?

Also would anything be needed for the back wall, as these 2 speakers are bipoles they need to rely on the reflective surfaces?

Will all of this be a massive improvement to the sound?

Will I have to move my sub again once putting bass traps in as I have a pretty good response at the moment and it will be a pain to start over again?

Thanks
Marty


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## bpape

If you've played with sub position to get the best response, the chances of having to move it a lot more are pretty slim. Maybe some slight improvements to be had with slight movements but nothing that you'd have to do right away certainly - or possibly not at all.

Yes - ideally, the front wall would be 100% covered with absorbing material.

Rear wall - not so much other than potentially some membrane type absorbers if you have problems with cancellations in the bass off of the rear wall. Those types will still allow the surround field to sound lively.

Bryan


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## marty1

bpape said:


> If you've played with sub position to get the best response, the chances of having to move it a lot more are pretty slim. Maybe some slight improvements to be had with slight movements but nothing that you'd have to do right away certainly - or possibly not at all.
> 
> Yes - ideally, the front wall would be 100% covered with absorbing material.
> 
> Rear wall - not so much other than potentially some membrane type absorbers if you have problems with cancellations in the bass off of the rear wall. Those types will still allow the surround field to sound lively.
> 
> Bryan


Thanks Bryan

How do I tell if I have bass cancellations with the bass from the rear wall?

The membrane type absorbers, where would they go, if you look at rear speakers and then imagine that they are now both further apart, about 1.5 feet from each side wall, these speakers are bipoles so would the membrane absorbers reflect the sound like bipoles are supposed to?

Kind Regards
Marty


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## bpape

All I'm looking for in the back is something that will absorb bass but not as much in the upper mids and highs to preserve the surround field.

If you move your mic forward or backward from the seating position, do you notice any nulls going away or changing in frequency? If either, then you have potential rear wall problems.

Bryan


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## marty1

bpape said:


> All I'm looking for in the back is something that will absorb bass but not as much in the upper mids and highs to preserve the surround field.
> 
> If you move your mic forward or backward from the seating position, do you notice any nulls going away or changing in frequency? If either, then you have potential rear wall problems.
> 
> Bryan


I did notice that there was a dip around 35-40hz that got steeper as I moved further away from the rear wall, about 2 feet from the rear wall seemed better. I still have to try out rew v5 properly, I tried it the other day and the results were different to what I got in version 4 so I still dont know how to use v5?

Thanks
Marty


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## bpape

Probably just a change in mic position. Or, could be you have smoothing set differently.

Bryan


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## marty1

bpape said:


> Probably just a change in mic position. Or, could be you have smoothing set differently.
> 
> Bryan


Does this null mean I have rear wall bass problems?

How do I absorb the front wall, I wouldn't be able to put much above the screen as there is only about 5 inches from the top of it to the ceiling, I do not know how to remove the screen as it fixed and was proffesionally installed, are you just talking about surrounding the screen with something?

If my subs response is pretty good why would I need bass traps in the 4 corners, what difference would it make to the sound? Would the untrained ear notice a difference?

Thanks Again
Marty


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## bpape

Do as much as you can on the front wall given the restrictions.

If you have a changing null based on seating position front to back, it can be helped with rear wall treatment coupled with good positioning.

For the other absorbers, remember that there is much more than just frequency response in play here. I can have perfectly flat response and excessive ringing and decay times that will muddy up sound, cause dialog intelligibility problems, cause loss of imaging cues and harmonic details, etc. 

Bryan


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## marty1

bpape said:


> Do as much as you can on the front wall given the restrictions.
> 
> If you have a changing null based on seating position front to back, it can be helped with rear wall treatment coupled with good positioning.
> 
> For the other absorbers, remember that there is much more than just frequency response in play here. I can have perfectly flat response and excessive ringing and decay times that will muddy up sound, cause dialog intelligibility problems, cause loss of imaging cues and harmonic details, etc.
> 
> Bryan


Thanks Bryan :T

So what you are saying is the bass traps will make the sound better to the ear but not necessarily visible through REW?

Regards
Marty


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## bpape

It will make it better in REW if you look at the decay time or waterfall windows as opposed to just the measured frequency response.

Bryan


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## marty1

bpape said:


> It will make it better in REW if you look at the decay time or waterfall windows as opposed to just the measured frequency response.
> 
> Bryan


Interesting, I wouldn't have the first idea on what to look at on those sceens :huh:

In regards to the front wall again, I saw a thread where a guy put a couple of corner shelves up and placed triangular cut slices of rockwool on top of eachother all the way up the wall. Is this the correct way of making a corner bass trap because I was under the impression that you need to leave a bit of air space between the rookwool and the corner?

Thanks
Marty


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## bpape

It's one way to do it and will work just fine.

The air gap is a common misconception. It's not the space, it's getting the leading edge of the absorber out farther from the hard boundary that helps extend performance. That said, any time you can have a solid chunk rather than a thinner chunk with an air gap (think 6" flat on a wall vs 4" with 2" of air), the solid piece will perform better. Same goes for flat panels straddling a corner vs solid triangular chunks.

Waterfalls are an easy graphical representation of how fast sound decays across the frequency spectrum. Bottom axis is frequency. Left axis is intensity (db level). Z axis (depth) shows time in milliseconds. The proper decay time varies by each room in terms of size and what you'll use the room for. Classrooms are different from churches from home theaters from listening rooms, etc.


Bryan


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## marty1

bpape said:


> It's one way to do it and will work just fine.
> 
> The air gap is a common misconception. It's not the space, it's getting the leading edge of the absorber out farther from the hard boundary that helps extend performance. That said, any time you can have a solid chunk rather than a thinner chunk with an air gap (think 6" flat on a wall vs 4" with 2" of air), the solid piece will perform better. Same goes for flat panels straddling a corner vs solid triangular chunks.
> 
> Waterfalls are an easy graphical representation of how fast sound decays across the frequency spectrum. Bottom axis is frequency. Left axis is intensity (db level). Z axis (depth) shows time in milliseconds. The proper decay time varies by each room in terms of size and what you'll use the room for. Classrooms are different from churches from home theaters from listening rooms, etc.
> 
> 
> Bryan


I understood it that the sound travels through the absorber reflects off the wall behind and then gets absorbed again?

What decay time would I be aiming for in a home cinema then? Would it be the same db level across all frequencies?

Thanks
Marty


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## bpape

True on the reflection - but - with a solid piece, it's doing the same thing but never leaving the absorbing material.

What are the room dimensions? That's part of the calculation.

The decay times will be a downward sloping curve which is somewhat flat in the middle with the low end being a bit higher and the high end being a bit shorter.

Bryan


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## marty1

bpape said:


> True on the reflection - but - with a solid piece, it's doing the same thing but never leaving the absorbing material.
> 
> What are the room dimensions? That's part of the calculation.
> 
> The decay times will be a downward sloping curve which is somewhat flat in the middle with the low end being a bit higher and the high end being a bit shorter.
> 
> Bryan


My room is 18ft 6inchesx12ft 11inches and 8.5ft high


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## bpape

From an RT60 standpoint (really more for larger rooms but OK for reference), you'd want to be around 200ms in the midrange - maybe 250 in the lows and 160-170ms in the high end. You're really more interested in RT30 which is a bit more than 1/2 of those times but most people don't like it that dead.

Untreated, the low end is now probably closer to 1 second or a bit more.

Bryan


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## marty1

bpape said:


> From an RT60 standpoint (really more for larger rooms but OK for reference), you'd want to be around 200ms in the midrange - maybe 250 in the lows and 160-170ms in the high end. You're really more interested in RT30 which is a bit more than 1/2 of those times but most people don't like it that dead.
> 
> Untreated, the low end is now probably closer to 1 second or a bit more.
> 
> Bryan


Thanks Bryan :T

I will measure on Saturday morning but I will probably need guidence if that is oklease:

I will post the results on here.

Just one more thing, how do you cut rockwool into triangles?

Regards
Marty

Regards


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## bpape

No problem.


Here is the cut pattern to turn 2'x4' sheets into 8 17x17x24" Triangles.



Use a sharp disposable razor knife to keep the blade sharp. 703 is more expensive but a lot easier to cut and work with.

Bryan


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## marty1

bpape said:


> No problem.
> 
> 
> Here is the cut pattern to turn 2'x4' sheets into 8 17x17x24" Triangles.
> 
> 
> 
> Use a sharp disposable razor knife to keep the blade sharp. 703 is more expensive but a lot easier to cut and work with.
> 
> Bryan


703?
Razor Knife?

Sorry :huh:

Over here I know in our D.I.Y. store Wickes or B&Q they sell rockwool in rolls 50mm thick, not sure where to get sheets from?

I assume a razor knife would be the same as our retractable stanley knives?


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## bpape

Pretty much the same thing. These would be disposable and have break off blades. Very thin blades, plastic housing, etc.

For sheets, look at an insulation supply house or a metal building insulation company.

Bryan


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## marty1

Yeah we call them Stanley knives, dont know why, dont know who stanley is :rofl2:


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## Moonfly

same reason we called a vacuum clean a hoover


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## bpape

marty1 said:


> Yeah we call them Stanley knives, dont know why, dont know who stanley is :rofl2:


I think he's married to Shirley


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## marty1

Moonfly said:


> same reason we called a vacuum clean a hoover


I thought Henry invented it 



bpape said:


> I think he's married to Shirley


That's an awfully big moustache


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## marty1

marty1 said:


> That's an awfully big moustache


Frank Drebbin (Naked Gun 2 1/2) if anyone didn't get it :dontknow:


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## grn1969c10

Marty, I haven't used the newer version of REW yet, (Maybe this week...) but I believe you can view the waterfall graph for any measurements you have already taken and saved to disk. In the older version You could reopen them and select the waterfall tab to generate the graph. I thought I would mention that so you didn't think you had to set up all the gear and remeasure just to see the decay times for your current situation.

Matt


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## marty1

grn1969c10 said:


> Marty, I haven't used the newer version of REW yet, (Maybe this week...) but I believe you can view the waterfall graph for any measurements you have already taken and saved to disk. In the older version You could reopen them and select the waterfall tab to generate the graph. I thought I would mention that so you didn't think you had to set up all the gear and remeasure just to see the decay times for your current situation.
> 
> Matt


Thanks Matt but the thing that I need to look into is why my response with REW V5 seems quite a bit different from my older REW response, I am now concerned that my old results may not have been accurate so I feel like I need to get to grips with V5 and remeasure, then I can see if I can match the original results, then I can start learning how to use the waterfalls.

I shall have ago tomorrow :T

Regards
Marty


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## marty1

bpape said:


> Broadband bass absorption floor to ceiling in the 2 front corners. I'd also do some in the shorter left rear corner.
> 
> I would add at least 2-3 2" 2'x4' absorption panels on the left wall to bring better left to right symmetry by matching better with the curtains on the other side.
> 
> Ideally, the front wall would also be 100% dead to help with boundary interactions and to prevent reflections from the surround channels contaminating the front soundstage.
> 
> Bryan


Do I also need to put a panel on the bit of wall next to the front left speaker, at the same height or will the 2-3 panles along the wall at mid height be sufficient. Also once the front wall is absorbed can I push the speakers right into the corner or are they still better off staying about 2 feet away?

Regards
Marty


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## bpape

Corner loading is almost never a good idea unless the speakers are specifically designed for it - which yours aren't. You would also like to try to make sure that the distance behind the speaker and the distance beside the speaker are not the same so the boundary interactions are different.

I'll have to go back and take a closer look on the short wall you're talking about.

Bryan


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## marty1

Here are my measured results for sub+mains

















Not sure how best to show results in waterfall?

Would also like to know how good the sub response is, as it sounds great to me?


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## grn1969c10

The waterfall should be converted to logarithmic scale. That should make it display correctly.

Matt


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## marty1

grn1969c10 said:


> The waterfall should be converted to logarithmic scale. That should make it display correctly.
> 
> Matt


I have tried it on rewv5 does this look any better?









If not how do I convert to logarithmic scale?

Thanks
Marty


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## kflory

marty1 said:


> If not how do I convert to logarithmic scale?


You can change the scale by clicking the "Freq-Axis" button in the top right corner above the graph.


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## marty1

kflory said:


> You can change the scale by clicking the "Freq-Axis" button in the top right corner above the graph.


What do I change it to?


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## kflory

marty1 said:


> What do I change it to?


It will toggle it between a linear and a logarithmic scale.


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## marty1

kflory said:


> It will toggle it between a linear and a logarithmic scale.


Which one is which? One goes down to 15hz the other only goes to 20hz?


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## bpape

You can move it around to set the bottom and the top frequency separately from changing linear to log.

FR isn't that bad other than a wide hole between 100 and 150Hz. Are the mains cut off or running concurrently and what is the xover set to? Are you running both the xover in the processor and the sub or just one? (Should be just one)

Also, FR appears to have some smoothing turned on. I would turn that off. 

For now, just concentrate FR and waterfalls from say 20-300Hz.


Bryan


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## marty1

bpape said:


> You can move it around to set the bottom and the top frequency separately from changing linear to log.
> 
> FR isn't that bad other than a wide hole between 100 and 150Hz. Are the mains cut off or running concurrently and what is the xover set to? Are you running both the xover in the processor and the sub or just one? (Should be just one)
> 
> Also, FR appears to have some smoothing turned on. I would turn that off.
> 
> For now, just concentrate FR and waterfalls from say 20-300Hz.
> 
> 
> Bryan


The mains are set to small, xo at 80hz, sub xo is fully open.

The smoothing can either be the mcaac on my pioneer amp, which to my untrained ears sounds better on than off, but it could be a mental thing, or I do have the parametric equaliser on the svs sub tuned to tame a large peak around 30hz? Or do you mean on rew there is smoothing to be turned off?

I have been trying to improve the sound from my bipole rears, finding the best position for them and the best seating position all round, so after trial and error the sound from the bipoles sound much better when I am seated closer to them, this means instead of 5 feet from the rear wall I am now 2 feet from it, I have measured the subs response in this position and I have it looking ok, is this an ok response and is 2 feet too close? I have tried the dipoles in various positions but this gives the best rear soundstage strangely enough, especially when something travels from left to right you really get a wide soundstage and clearly hear the movement from 1 side of the room to the other.

(This is mainly for sub response and this is with mcaac eq off, mains and sub xo on amp 80hz)









Thanks again Bryan

Regards
Marty


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## bpape

2 feet would normally be too close. You're sitting in a lot of bass buildup and severely limiting your surround experience. 

Just remember than any EQ done at one seating position would need to be redone at any new position. Things will change drastically.

I was referring to smoothing in REW.

Bryan


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## marty1

bpape said:


> 2 feet would normally be too close. You're sitting in a lot of bass buildup and severely limiting your surround experience.
> 
> Just remember than any EQ done at one seating position would need to be redone at any new position. Things will change drastically.
> 
> I was referring to smoothing in REW.
> 
> Bryan


I was always told to use 1/3 octave smoothing.

What is an ideal minimum distance to be from a rear wall? Are the results showing an increase in bass by moving closer?

The problem like I said was I seem to loose the details in the rear soundstage further out into the room, is there a reason for that?

Thanks
Marty


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## bpape

1/3 octave obscures detail. I would recommend turning it off for this exercise.

Ideal seating distance is a function of room length. 

I can't say what's happening when you move without having both measurements done with no smoothing and no EQ applied

If you're losing detail by moving to farther away from the wall, the surrounds are not likely in the right place - or you're expecting to hear too much from them. 

Bryan


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## marty1

bpape said:


> 1/3 octave obscures detail. I would recommend turning it off for this exercise.
> 
> Ideal seating distance is a function of room length.
> 
> I can't say what's happening when you move without having both measurements done with no smoothing and no EQ applied
> 
> If you're losing detail by moving to farther away from the wall, the surrounds are not likely in the right place - or you're expecting to hear too much from them.
> 
> Bryan


My room length is 18 feet?

In regards to the surrounds I sat in the 5 feet from rear wall position and moved the speakers around on ladders testing material, the rear wall about 1 and a half feet from the corners sounded best, then I was trying seating position and i found that closer to them there is details I can hear which I cannot from the 5 feet position. The main thing I noticed is on the thx scene on indy 4 bluray, when the flowers start fluttering around the rear speakers the finally shift across the rear soundstage from left to right, when I sit in the 5 feet forward position you cant really tell what direction the fluttering goes?


This is the results without amps eq and without smoothing, the only thing that was applied was I adjusted the phase to raise a large dip around 50-60hz and the svs subs parametric equaliser to iron out a large peak around 35hz.

2 feet from wall








5 feet from wall








Thanks
Marty


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## bpape

Looks to me like 5' away is much smoother response without the null and peak.

As for the surround details, some of that is purely a function of excessive decay time and the bottom end not being tight that's masking the details. Try an experiment and move the surrounds on ladders within a couple feet of you when you're 5' from the wall and see what you think. You can also try 5' with them at the rear wall and just turn off the sub to avoid the boom and excessive ringing in the bass - at least from 80hz down.

Bryan


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## marty1

bpape said:


> Looks to me like 5' away is much smoother response without the null and peak.
> 
> As for the surround details, some of that is purely a function of excessive decay time and the bottom end not being tight that's masking the details. Try an experiment and move the surrounds on ladders within a couple feet of you when you're 5' from the wall and see what you think. You can also try 5' with them at the rear wall and just turn off the sub to avoid the boom and excessive ringing in the bass - at least from 80hz down.
> 
> Bryan


Thanks Bryan I shall try that tomorrow as it is bed time over here now!

Are you able to suggest an ideal distance from rear wall to seating position in a room 18ft 6inch in length?


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## bpape

In theory, you'd want to be somewhere between 6' and 7' from rear wall to seated ear position. That's theoretical but it usually falls somewhere in that range.

Bryan


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## marty1

bpape said:


> In theory, you'd want to be somewhere between 6' and 7' from rear wall to seated ear position. That's theoretical but it usually falls somewhere in that range.
> 
> Bryan


Thanks Bryan :T

The only problem with that is it puts me too close to the 16:9 pj screen, this is 9 feet wide by just over 5 feet high, I was informed by the installer that ideally you need to sit no closer than around 3 times the height of the screen distance away, this means that 3 feet is really all I should have from me to the rear wall, but I just about got away with 5 feet forwards, my wife wasn't too keen on the couch being there as it made the room feel a lot smaller and it was in between the 2 doors so you have to squeeze around it.

So I guess I should get it back to 5 feet? Although it is smoother than the 2 feet from rear wall response, would you class that as a very good response or is there still a lot of work to be done?

Thanks again Bryan

I am now gonna make my wife happy and tell her to get off the couch so I can do some more mad scientist stuff :bigsmile:


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## bpape

Yeah - that can be a problem getting a screen before you establish seating position so the screen is driving seating instead of the other way around. 

5' is better than 2-3' certainly and the response shows it. I've seen a lot worse response, trust me. Still needs some work but it's a better starting point.

Bryan


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## marty1

I will remember that next time!

I just realised that I was actually sitting 4 feet not 5 feet from the rear wall! Again looking at 5 feet feels too close to the screen and is in the middle of the doors so I am even further back than I thought!!

When you say that response needs work I take it you mean with room treatment as I have done all I can with placement?

Thanks
Marty


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## bpape

You could still potentially play with speaker and sub locations to see if anything else can be done. Treatment can add additional help but I'd like to get you as good as possible before hand so we can best identify what is causing the remaining problems.


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## marty1

bpape said:


> You could still potentially play with speaker and sub locations to see if anything else can be done. Treatment can add additional help but I'd like to get you as good as possible before hand so we can best identify what is causing the remaining problems.


Thanks again Bryan, appreciate it. I have tried every possible location for sub, the only extent I haven't gone to is moving the sub an inch at a time and measuring but that would take a very long time.

I tried the bipoles on ladders 2 feet behind me in the 5 feet foward (sorry 4 feet!) position and I think you were right because they dont sound much different now. I also tried listening to different film clips and moving them about. I tried them on the side wall, 1 tweeter facing towards me the other firing behind, I am not sure how the sound is meant to be heard from a bipole but they sound quite a bit different. I have been informed that they work on back or side walls. I watched the matrix where neo gets shot at by the agent and found on the side wall sounded great but very directional but on the rear wall it was less directional but seemed to be a bit less fluent when the first bullet whizzes down the left hand side of the room?


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## bpape

Well, bipoles by nature would be hung with you sitting directly inside of them so you're in the null and they're not localizable. Back wall, I usually recommend monopoles. 

The clarity is better now since you're away from where all the bass is building up and masking things back closer to the wall.

Bryan


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## marty1

bpape said:


> Well, bipoles by nature would be hung with you sitting directly inside of them so you're in the null and they're not localizable. Back wall, I usually recommend monopoles.
> 
> The clarity is better now since you're away from where all the bass is building up and masking things back closer to the wall.
> 
> Bryan


That is strange about the bipoles, I always sat in the null as I originally thought they were dipoles and had them on the side wall. Someone from cedia said that they are 2 close to the rear wall (2 feet) and would be better placed on the rear wall 1/3 the width of the wall apart. When I moved them there the sound was poor! We were still sitting in the nulls but was really disappointed with the rear soundstage, I could never hear much going at all, like I never even had any rear speakers. Then I was told by the store I bought them from that they are bipoles not dipoles and you are meant to have 1 of the tweeters firing at you and the other firing away from you and reflecting, he then said that they are best placed on the rear wall about 8 feet apart (the rear wall is 13 feet wide) I did this and this is when the rear soundstage really opened up and the width of sound was incredible. Now trying them on the side wall with 1 tweeter firing at us, they are kind of in a monopole placement position in a standard 5.1 layout. I think they sound even better there but not sure, the matrix scene where neo is shot at the bullet seems to have a smoother transition from front left speaker and travels all the way along the side wall to the rear, I would assume that that is exactly how it is supposed to be heard?

Regards
Marty


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## marty1

bpape said:


> If you're losing detail by moving to farther away from the wall, the surrounds are not likely in the right place - or you're expecting to hear too much from them.
> 
> Bryan


I am curious to know what are we actually supposed to be hearing from surrounds, I can hear when loud things happen like things flying around or bullets whizzing past but for 95% of a film I cant hear anything, if you walk up to a surround speaker there is always sounds coming through them for the whole film, surely if there is sound details coming from them you are supposed to hear them otherwise why bother putting any info on rear channels other than fly pasts?



bpape said:


> Well, bipoles by nature would be hung with you sitting directly inside of them so you're in the null and they're not localizable. Back wall, I usually recommend monopoles.
> 
> The clarity is better now since you're away from where all the bass is building up and masking things back closer to the wall.
> 
> Bryan


http://forum.blu-ray.com/speakers/66471-guide-bipolar-dipolar-direct-radiating-monopole-surround-speakers.html
This is why I placed my speakers where they are now and for the major sound effects they sound best in the rear wall position in my room, the side wall was too localised. Notice that for bipoles you are not in the null.
http://forum.blu-ray.com/speakers/6...ect-radiating-monopole-surround-speakers.html

Kind Regards
Marty


----------



## TypeA

Youre hearing exactly what you should from the surrounds, only occasional sound effects. Some movies and sources are better at utilizing the surrounds than others. So much so that movie reviews often mention how active the surrounds were throughout the movie...


----------



## marty1

TypeA said:


> Youre hearing exactly what you should from the surrounds, only occasional sound effects. Some movies and sources are better at utilizing the surrounds than others. So much so that movie reviews often mention how active the surrounds were throughout the movie...


What is the point of the sound effects coming from the surrounds then? I am reffering to the jungle noises or the people mumbling or rain pouring etc. etc.

I would have thought they mixed those sounds there to make you feel like you are in the movie?


----------



## bpape

For exactly what it says the are - surround effects. Mostly, it just adds a sense of envelopment and being IN the movie instead of outside of it. There are some effects that should be heard loud and clear but many are just ambient type of things.

Bryan


----------



## marty1

bpape said:


> For exactly what it says the are - surround effects. Mostly, it just adds a sense of envelopment and being IN the movie instead of outside of it. There are some effects that should be heard loud and clear but many are just ambient type of things.
> 
> Bryan


I am not sure I am even hearing the ambience, I suppose I could try unplugging front speakers and listen to what I am actually hearing but I watched harry potter & the P.O.A. and didn't notice any rear ambience, I know you are not supposed to be distracted but since I am going all out to try and perfect the sound as best as I can I was actually listening to hear what was going on and there was nothing. If I turned my head sideways I can suddenly hear the sound but when I stare straight at the screen nadda! Unless it is a flyover sound effect.

Kind Regards
Marty


----------



## bpape

Try the opposite and play a scene. Then replay with the rears disconnected.

Bryan


----------



## marty1

:


bpape said:


> Try the opposite and play a scene. Then replay with the rears disconnected.
> 
> Bryan


That's an interesting one I will give it a try and see what happens.

Thanks Bryan :T


----------



## TypeA

marty1 said:


> I am not sure I am even hearing the ambience, I suppose I could try unplugging front speakers and listen to what I am actually hearing but I watched harry potter & the P.O.A. and didn't notice any rear ambience, I know you are not supposed to be distracted but since I am going all out to try and perfect the sound as best as I can I was actually listening to hear what was going on and there was nothing. If I turned my head sideways I can suddenly hear the sound but when I stare straight at the screen nadda! Unless it is a flyover sound effect.
> 
> Kind Regards
> Marty


Try processing with all channel stereo via your receiver, that will send the entire soundtrack to all speakers. If you are noticing a loss of rear performance while processing in a surround mode (like truehd dtsmaster dolby digi ect) then its the mastering of your source and not your setup. Speaker level calibration software within your receiver will send white noise to each channel also.


----------



## marty1

TypeA said:


> Try processing with all channel stereo via your receiver, that will send the entire soundtrack to all speakers. If you are noticing a loss of rear performance while processing in a surround mode (like truehd dtsmaster dolby digi ect) then its the mastering of your source and not your setup. Speaker level calibration software within your receiver will send white noise to each channel also.


My speakers are all calibrated to 75db from my listening position, I tried all channel stereo and sounds good all round so it is probably the source as you said.

I tried unplugging all speakers and sub except the surrounds in the flying tank scene in the A-Team, there were surrounds effects galore that I could clearly hear every detail of, then I tried all 5 speakers on and I was unable to hear most of the effects that I heard from surrounds alone?

I then tried what Bryan suggested and just turn the 3 fronts on and I could hardly tell any difference between the surrounds being on or off.

I have only tried this with the A-Team bluray and nothing else so far but what is going on?

Regards
Marty


----------



## Gregr

C'mon guys "Stanley Tools" developed the Utility Knife/razor knife/retractable knife ect. we've always called them utility knives here in Maine. But , the "Skill Saw" that was a tough thing for me to start calling a circular saw/power saw. But Skill Tools did first come out with a circular saw so naturally one would call this a skill saw. Right? 

In any case, Bryan I hate to distract you from the great job you are doing with Marty1 (I have some idea now) and it is probably bad form too. I am just curious (well more than curious). I am reading Stereophile January 2011 and a couple of the columnists have gone souh to visit the Univ of the South in Tenn. where they have gone to examine, critically evaluate a "Million Dollar Stereo System". The entrance to the lisening room even has a sound lock vestibule entrance where like an air lock you enter the vestibule, close the door behind you and then open the door to the listening area. They describe some pretty exotic sheetrocking practices and shelving alignments and other very sophisticated room considerations. They are using a single pair of Wilson's newer Grand Slam speakers..., I forgot the name of this model but they are huge Wilson Audio speakers.
But when I look around what I see for noise Tx are 3' x 6' panel directly behind the speaker and a 2'x2' on the ceiling which which lies beginning just off mid-line of the Wilson's and the area toward center-line of the room and just forward of the speakers. The shelving lining both L/R walls are angled so that any sound reflection trapped by the shelving and dissipates. I don't know about the back wall there were no pic's I guess this is where the special sheet-rock was used. But after reading what you suggest and sounds perfect to me. I just wonder how the library gets by with so little damping around the speakers themselves.

Gregr


----------



## bpape

IMO, the room is undertreated. There have been a lot of things done to maximize the 'starting point' which is always a good thing.

How they get by with it is that most people don't know any better quite honestly.


----------



## marty1

marty1 said:


> My speakers are all calibrated to 75db from my listening position, I tried all channel stereo and sounds good all round so it is probably the source as you said.
> 
> I tried unplugging all speakers and sub except the surrounds in the flying tank scene in the A-Team, there were surrounds effects galore that I could clearly hear every detail of, then I tried all 5 speakers on and I was unable to hear most of the effects that I heard from surrounds alone?
> 
> I then tried what Bryan suggested and just turn the 3 fronts on and I could hardly tell any difference between the surrounds being on or off.
> 
> I have only tried this with the A-Team bluray and nothing else so far but what is going on?


Anyone got any suggestions at all?


----------



## bpape

I would try that experiment with a different movie - one that has more ambient effects like being in a jungle, water dripping in a cave, etc. If the level is just too low for your preference, then there's nothing wrong with adjusting it up a bit to suit your taste.

Bryan


----------



## marty1

bpape said:


> I would try that experiment with a different movie - one that has more ambient effects like being in a jungle, water dripping in a cave, etc. If the level is just too low for your preference, then there's nothing wrong with adjusting it up a bit to suit your taste.
> 
> Bryan


I am looking at the placement again, with the left surround bipole, the tweeter firing towards me is firing at the back of my head, I wonder if that is affecting the sound?

When I experimented with placement I used material with loud surround effects to decide the final position, I found that on the side wall when the helicopter at the start of cliffhanger flies from the left surround and goes around the room, just before the picture first comes on, I could tell exactly where the leftspeaker was. This is why I chose rear placement instead but should I have tried watching a whole film with them on the sides before giving up?

Maybe the ambient sounds would have sounded better from that position?

Regards
Marty


----------



## bpape

Again, I can't say. It's a lot of personal preference and what YOU want from the surrounds. It's certainly possible that you might prefer the other location on other movies.


----------



## marty1

bpape said:


> Again, I can't say. It's a lot of personal preference and what YOU want from the surrounds. It's certainly possible that you might prefer the other location on other movies.


I will give it a try in the side position and leave them there whilst watching a few films, that might give me more confidence in my decision, then I can focus my attention back to your room treatment suggestions.

Got a bit sidetracked :R Thanks for your help again Bryan, much appreciated :T


----------



## Gregr

Bryan,

Sounds like Marty1 has a list of do's and will be busy for a bit. I just have a quick follow-up on the Stereophile trip to the Univ of the South in Tennessee. 

After reading your response, I again looked over the article and there were a few things that now do stand out as different. The article was spread out over a dozen pages or so with a total of 5-7 leaves (verso and/or recto) total dialog. The article I will admit was about the trip but the critique was more about the trip, buying LP's at a NJ Market, eval of the New Ford Edge sound system and lots of other critical stuff.

The actual written dialog about the Univ's $1m sound room consisted of one of two columns on one leaf. The article mentioned a few building materials and construction considerations. included were names of the materials and Architects/Engineers but no "Sound Engineer" specifically. And there was no real critique as you would expect for such a grand effort. There were some superlatives and even a little emotional gushing about the Wilson Alexandria's but fell way short of a total package critique. Not like Stereophile to miss an opp to write on and on about all of the details. Chris Huston was credited with the Acoustical Engineering in one line no longer than line I just gave you. 

Bryan, all of that sounds odd but here is a question that leads to my real question. Can you "Over-dampen a room"? And the real question is: my speakers sound great (matched pair of B&W DM303's especially) if I am standing 3 ft away from one I cannot tell you which speaker is actually playing what I hear (to a very high degree). If I use the 5.1 I can point out the Mission sound track. Will damping improve my speaker invisibility.
if I over-damp will my speakers become obvious or if they are well matched will they disappear even further. I have a sense that all of the speakers flaws will add or multiply. Sorry I didn't mean to go on for so long, but I believe you are the man to answer this one.

Thanks 

Greg


----------



## bpape

Honestly, for the sake of your question and the sake of his thread, it would be better if we did this in your own thread.

Bryan


----------



## Gregr

Thanks 
Good idea I think I will ask for some ideas.

Greg :heehee:


----------



## marty1

bpape said:


> Honestly, for the sake of your question and the sake of his thread, it would be better if we did this in your own thread.
> 
> Bryan


HEHE......HIJACKER ALERT :foottap:


----------



## marty1

bpape said:


> Broadband bass absorption floor to ceiling in the 2 front corners. I'd also do some in the shorter left rear corner.
> 
> I would add at least 2-3 2" 2'x4' absorption panels on the left wall to bring better left to right symmetry by matching better with the curtains on the other side.
> 
> Ideally, the front wall would also be 100% dead to help with boundary interactions and to prevent reflections from the surround channels contaminating the front soundstage.
> 
> Bryan


Ok I am now thinking about making a stud wall for the front wall, mainly due to hearing my neighbours during quiet scenes in films, I have read how to do this and what I was wondering was would making the standard stud wall create the absorbtion I need?

I would loose about 6 inches of the room with the stud wall so I would prefer to avoid adding absorbant panels all around the front wall afterwards.

Regards


----------



## bpape

To provide isolation, you need studs, insulation, and drywall. That's not going to give you any absorption for reflections from the surrounds or help with boundary issues.

Why 6"? 

Bryan


----------



## marty1

bpape said:


> To provide isolation, you need studs, insulation, and drywall. That's not going to give you any absorption for reflections from the surrounds or help with boundary issues.
> 
> Why 6"?
> 
> Bryan


That was the final depth of a studwall away from existing wall drawing I saw, It was thick rockwooll against existing wall, then a 4 inch gap, then 2 layers of accoustic plasterboard with a layer of rockwool sandwiched inbetween them.

So I am guessing I would need to add another layer of rockwool on top of the plasterboard and just cover with a layer of fabric then?

Regards
Marty


----------



## bpape

You can cut the spacing a little. The rockwool between drywall layers isn't going to do much at all. Green Glue would be better by a long shot.

Assuming Green Glue.

Wall
1/2" space
2x4 stud(3.5")
2 layers 1/2" drywall

Total space - 5". That leaves you only using 6" total with 1" mineral wool inside the room or 7" total with 2" inside the room.

Bryan


----------



## Tooley

Or you can use the same as above but instead of 2 sheets you can omit that for 1 1/2" sheet of quite rock which is equal to 8 1/2" sheets of standard drywall and 12" of Safe and Sound.


----------



## bpape

I would quadruple check those specs. No way is 1.5" QuietRock going to have that kind of performance - not to mention that it's outrageously expensive for the 1.5" and you'll need at least 3 guys to wrangle it around.

It's not a bad product, don't get me wrong, but the DD and GG is WAY less expensive and will give you 95% of the performance.


----------



## Tooley

I agree that it is expensive but it is only 1/2" thick not 1 1/2" it weights the same as a regular 1/2" sheet it is 2 1/4" sheet laminated together with a product similar to green glue we use it all the time so does Paradigm at there lab and also Mike Holmes he stated the specs on his show awhile ago. In our area we supply install tape mud prime and paint for $285.00 a sheet and we are told that we are on average $20-30 less a sheet then most of the other contractors.


----------



## bpape

Sorry. Misread your post and thought you were referring to the 1.5".

I'll still stick with the 2 layers of 1/2" and green glue for better performance at the cost of 1/2" of space. I'm not saying it's not a good product at all. Looking at the quiet rock performance data for the 1/2", they show at TL of 17 at 100Hz, 27 at 125, and 33 at 160. GG plus 2 layers 1/2" shows 22 at 100Hz, 30 at 125Hz, and 35 at 160hz. GG also shows 21 at 80hz.

Overall STC
GG assembly - 54
QR assembly - 49

Keep in mind that STC is an average and not an end all. Where the GG assembly shines is at the low end where it's more difficult to stop sound. That's a function of the additional mass of 2 layers of 1/2" vs 2 layers of 1/4".

That said, even at higher frequencies, the GG assembly is superior. At 5kHz - the GG assembly has a TL of 70, the QR assembly has a TL of 58. 

All of these data points come directly from the respective companies' test result documentation from their own web sites.


For your own perusal

http://www.greengluecompany.com/images/transmissionLossTests/OL05-0823_Report.pdf

http://www.quietrock.com/documentation/func-startdown/94/


----------



## Tooley

bpape are you located in the US or Canada I am in Canada I can not get green glue here I called a few places that are suppose to carry it but they told me it is very hard to get here for some reason it would be alot more cost effective like you stated.


----------



## bpape

Contact Ted at The Soundproofing Store. He has good pricing and I know he ships to Canada at a reasonable price.

If you can get the QuietRock locally, I understand the situation certainly. Just pointing out the facts in specs and performance.


----------



## Tooley

Thanks for the contact.
Great talk.
Talk soon


----------



## marty1

bpape said:


> You can cut the spacing a little. The rockwool between drywall layers isn't going to do much at all. Green Glue would be better by a long shot.
> 
> Assuming Green Glue.
> 
> Wall
> 1/2" space
> 2x4 stud(3.5")
> 2 layers 1/2" drywall
> 
> Total space - 5". That leaves you only using 6" total with 1" mineral wool inside the room or 7" total with 2" inside the room.
> 
> Bryan


So what you are saying is instead of putting the rockwool on the existing wall just start off with space then studwall, then rockwool last with fabric covering?

The only problem is I think I need a solid wall to put my fixed pj screen onto?

Would it be just as effective in my room to have the rockwool going on the wall all around the outside of the screen and put in corner bass traps?

Kind Regards
Marty


----------



## bpape

What I'm saying is build a standard stud wall, insulate it with regular fluffy insulation, and drywall the surface. Then mount the screen on that wall. Cover the remaining wall with mineral wool or fiberglass (higher density) and cover with black cloth. 

That will give you the absorption you require, the isolation you want, and the 2" absorption with cloth will actually 'recess' the screen back a bit forming a nice looking shadow box effect.

You'll still need the corner absorption.


Bryan


----------



## fitzwaddle

Wouldn't that wall in front of a wall result in a triple leaf?


----------



## bpape

Not at all. You have concrete and the double drywall - 2 leaves of mass.


----------



## fitzwaddle

bpape said:


> Not at all. You have concrete and the double drywall - 2 leaves of mass.



Oops, my mistake, I didn't read back far enough, thought the wall it was going in front of was stick built with drywall.


----------



## marty1

bpape said:


> What I'm saying is build a standard stud wall, insulate it with regular fluffy insulation, and drywall the surface. Then mount the screen on that wall. Cover the remaining wall with mineral wool or fiberglass (higher density) and cover with black cloth.
> 
> That will give you the absorption you require, the isolation you want, and the 2" absorption with cloth will actually 'recess' the screen back a bit forming a nice looking shadow box effect.
> 
> You'll still need the corner absorption.
> 
> 
> Bryan



OK Thanks Bryan :T

I will have to get a builder to do this for me as It is completely out of my league, I struggle to put a shelf up:R

I will first of all have a go at making 3 (2x4) sound absorbers for the bare wall opposite the wall covered in blackout curtains.

Then I will buy some diffusers for the rear wall as these are probably out of my league to make myself?

I am hoping after I do this the slap echo should be gone?

Then finally the corner traps and the stud wall.

Bryan at the start of this thread you said that my REW response needed improvement, did you mean just the upper frequencies like 100hz and above or the sub response aswell? I dread the thought of having to move the pb13u again :yikes: So if there will be hardly any noticeable difference in the remaining improvements I can squeeze out of the sub then I would rather just leave that be and focus on the upper range?

Thanks for your help

Kind Regards
Marty


----------



## bpape

Up to you. Seating position and sub position can do a lot to change frequency response. 

Bryan


----------



## marty1

bpape said:


> Up to you. Seating position and sub position can do a lot to change frequency response.
> 
> Bryan


What I mean is looking at the subs response I got, which looked fairly good to me (I think it was within the +5/-5 range pretty much), is can this subs response be noticeably improved on? It sounds nicely balanced to my ears, not too boomy, powerful when needed so to go back and start moving everything again I would rather be sure that I will actually be able to sit down and hear the difference between this response and the potentially flatter response I may be able to achieve? Or will it now be just more peace of mind to see that flatter line?

Kind Regards
Marty


----------



## bpape

If you're happy with the results as is, then leave it. That's all that really matters. Yes - you can spend a lot of time to get a little flatter response but if you're good pre-treatment with the response, then you're way ahead of the curve.

Bryan


----------



## marty1

Thank You :T

I will keep you posted on my dodgy diy results :rolleyesno:


----------



## Ted White

Tooley said:


> 1 1/2" sheet of quite rock which is equal to 8 1/2" sheets of standard drywall


No data to support their matketing sound bite.

It all boils down to mass and how much damping material is used. You'll find that any low-mass panel will not get you much isolation. Also lower cost pre-damped panels simply have less damping compound. 

You'll find that a much better wall can be obtained just as Bryan stated. Standard (heavy) 5/8" drywall and a field application of a damping compound. Less expensive, less waste and better.


----------



## marty1

Ted White said:


> No data to support their matketing sound bite.
> 
> It all boils down to mass and how much damping material is used. You'll find that any low-mass panel will not get you much isolation. Also lower cost pre-damped panels simply have less damping compound.
> 
> You'll find that a much better wall can be obtained just as Bryan stated. Standard (heavy) 5/8" drywall and a field application of a damping compound. Less expensive, less waste and better.


I know I will probably sound thick here but what is the difference between the material used to make a stud wall and the drywall panels? I thought the the drywall panels were what makes up the stud wall?

Also do you ship green glue to the uk? How much would I need to do this project, the main wall will be 12ft 11inch by 8ft 5inch

Kind Regards
Marty


----------



## fitzwaddle

marty1 said:


> I know I will probably sound thick here but what is the difference between the material used to make a stud wall and the drywall panels? I thought the the drywall panels were what makes up the stud wall?
> 
> Also do you ship green glue to the uk? How much would I need to do this project, the main wall will be 12ft 11inch by 8ft 5inch
> 
> Kind Regards
> Marty


That would be the studs - a.k.a. dimensional lumber, a.k.a. 2x4s, 2x6s, etc. The drywall just covers up the studs.

But reading my answer, I must have misunderstood your question as stated. :sweat:


----------



## marty1

fitzwaddle said:


> That would be the studs - a.k.a. dimensional lumber, a.k.a. 2x4s, 2x6s, etc. The drywall just covers up the studs.
> 
> But reading my answer, I must have misunderstood your question as stated. :sweat:


No not really, so when you say lumber is that plasterboard, I want to make sure I get the right materials.

Is drywall a specialist thing?

Regards
Marty


----------



## Moonfly

marty1 said:


> No not really, so when you say lumber is that plasterboard, I want to make sure I get the right materials.
> 
> Is drywall a specialist thing?
> 
> Regards
> Marty


Lumber = Timber, Dry wall = Plaster board :T


----------



## fitzwaddle

Oh, haha, I get it now, we're talking two different dialects of English, that's the problem. Looks like Moonfly has that sorted. I should spend more time on the UK HT (I mean HC) site to stay bilingual - or bi-dialectical.


----------



## marty1

fitzwaddle said:


> Oh, haha, I get it now, we're talking two different dialects of English, that's the problem. Looks like Moonfly has that sorted. I should spend more time on the UK HT (I mean HC) site to stay bilingual - or bi-dialectical.


Yeah we are English so English English please :bigsmile:

I am going to the toilet.....sorry restroom :R

Such a colourful language we speak....... sorry again, I mean colorful :rofl2:


----------



## fitzwaddle

Wait, don't you mean going to the loo? Or maybe that's South African or Australian English.:dumbcrazy:


----------



## marty1

I have edited this comment off in case anyone was offended :nono:

I will have to bring this conversation out of the "loo" again 

Thanks so timber/plasterboard got it :T

Regards
Marty


----------



## marty1

I was talking to a guy at custom audio designs about diffusers to go on the rear wall as I will not capable of building them, he recommended these http://www.customaudiodesigns.co.uk/diffusers/skyline.htm

My wife hit the roof when I showed her :R 

They do a flat panel that she said would be acceptable, they did say it would not be as good but would these do the job http://www.customaudiodesigns.co.uk/diffusers/baddiff.htm

What my wife is concerned about is making our living room look like a studio and then when we listen there is no noticeable difference, I would say I am concerned about this too, will we hear a big difference, the main noticeable problem to my untrained ears is when I clap I can hear a slight echo, maybe with films slightly enhanced ssss on speech?

The other thing this guy suggested when I told him I am making absorbers for the bare wall on the left side of the room he said that as I have curtains covering most of the opposite side wall he said the absorbers wouldn't be any good, I need to put curtains down the left side of the room to balance the sound, is this correct? Will it be a waste of time making my absorbers?

I did suggest the curtains but you can imagine her reaction to this :R she said she would actually prefer absorbers disguised as pictures or with just basic fabric to match decor. Will it still make a difference having the absorbers rather than having curtains?

Thanks in advance.

Kind Regards
Marty


----------



## bpape

Hard to say. Diffusion is a much more subtle effect for those who aren't critically listening.


----------



## marty1

bpape said:


> Hard to say. Diffusion is a much more subtle effect for those who aren't critically listening.


Well considering it is around £500 for the diffuser panels to fill up the middle space on the rear wall it will be quite a gamble.

Will the sound absorbers on the side wall disrupt the balance having curtains opposite or can it be evened out just as well, again the curtain on bare wall would like rather odd, most of the room will be covered in curtains!


----------



## bpape

Panels would at least offset the higher frequency absorption from the other wall though they will reach lower (not necessarily a bad thing)


----------



## marty1

That's good to hear :T

Would I be better off making the panels with 25mm rockwool instead of 50mm to try and get closer absorbtion to what the curtains are providing (not very much I know, but I have no choice whatsoever to have curtains that side)


----------



## bpape

50mm will be fine. No need to further skew the high frequency absorption compared to the rest of the spectrum.


----------



## marty1

Thanks Bryan


----------



## marty1

marty1 said:


> My room length is 18 feet?
> 
> In regards to the surrounds I sat in the 5 feet from rear wall position and moved the speakers around on ladders testing material, the rear wall about 1 and a half feet from the corners sounded best, then I was trying seating position and i found that closer to them there is details I can hear which I cannot from the 5 feet position. The main thing I noticed is on the thx scene on indy 4 bluray, when the flowers start fluttering around the rear speakers the finally shift across the rear soundstage from left to right, when I sit in the 5 feet forward position you cant really tell what direction the fluttering goes?
> 
> 
> This is the results without amps eq and without smoothing, the only thing that was applied was I adjusted the phase to raise a large dip around 50-60hz and the svs subs parametric equaliser to iron out a large peak around 35hz.
> 
> 2 feet from wall
> View attachment 26720
> 
> 
> 5 feet from wall
> View attachment 26721
> 
> 
> Thanks
> Marty





bpape said:


> You could still potentially play with speaker and sub locations to see if anything else can be done. Treatment can add additional help but I'd like to get you as good as possible before hand so we can best identify what is causing the remaining problems.


Okay it's been a while but I have not been adding any room treatments yet, I have however managed to get the subs and mains response as best as possible in my room, it is looking a lot better than before, so now I need to begin room treatment, I seem to have a problem above 120 hz, I have the speakers crossover at 80hz on amp, when I measured left and right mains speakers by themselves I found that the front left speaker, which has all bare wall to the side of it measured pretty flat, the right speaker which has all curtains along the side wall (covering a window) is all over the place.

I have experimented with the mains as much as poss and found that I have to have them about half a foot from the side walls and about 2 inches from the front wall (just behind them) If I move them away from these walls the dips above 120hz become more prominent.

What do I need to do next? although the sound is really good I still feel that the sound can be softened a tad and maybe a bit more upper bass punch is needed, I still have bare back wall that could do with some diffusion and the left hand side of the room is all bare wall. I can only afford to do a bit at a time so I am thinking the rear wall diffusion should be attented to first but I would appreciate your advise again please Bryan :bigsmile:

Just to add I found that sitting any closer to the screen than 3 feet from the rear wall was too much for the eyes to take so this is the final seating position.


----------



## bpape

Are you using the xover on your processor and on the sub? Should just use the one on the processor and max or defeat the one on the sub. 

If speaker positioning that close to a boundary, you're using SBIR to tame another problem. We just need to see where it's coming from. If you move them out farther, what do you need to do in terms of mic position to get it to move/change intenstity? Forward/back movement? Side to side movement? Vertical?

Bryan


----------



## marty1

bpape said:


> Are you using the xover on your processor and on the sub? Should just use the one on the processor and max or defeat the one on the sub.
> 
> If speaker positioning that close to a boundary, you're using SBIR to tame another problem. We just need to see where it's coming from. If you move them out farther, what do you need to do in terms of mic position to get it to move/change intenstity? Forward/back movement? Side to side movement? Vertical?
> 
> Bryan


I am just using amps XO the sub is fully open.

SBIR?

I will have to work around the wife when I get a chance, so what you are saying is I need to move the speakers away from the walls and remeasure with the mic in different positions around my main listening position is that right?

Just out of curiousity does it look like I have tamed any noticeable problems with the subs response, I've posted a waterfall too but I have no idea how they work, I assume it is important to look at when beginning room treatments?

Marty


----------



## bpape

SBIR is a boundary related bass anomaly caused by spherical bass radiation pattern causing constructive and destructive (peaks and nulls) due to quick, strong reflections from nearby surfaces. 

It is likely that those are compensating for problems related to seating position or other problems that could potentially be addressed with treatments. 

Bryan


----------



## marty1

bpape said:


> SBIR is a boundary related bass anomaly caused by spherical bass radiation pattern causing constructive and destructive (peaks and nulls) due to quick, strong reflections from nearby surfaces.
> 
> It is likely that those are compensating for problems related to seating position or other problems that could potentially be addressed with treatments.
> 
> Bryan


So does that mean I need to measure around my listening position with speakers away from the walls to get an idea of where to treat?


----------



## bpape

My first shot would be to leave everything as is and just move the mic back or forward say 12-18" and take another measurement and see what that dip does. Whenever taking more measurements, only move one thing at a time so we KNOW what's going on.

Bryan


----------



## marty1

bpape said:


> My first shot would be to leave everything as is and just move the mic back or forward say 12-18" and take another measurement and see what that dip does. Whenever taking more measurements, only move one thing at a time so we KNOW what's going on.
> 
> Bryan


Ok I will give it a try, the only problem I do have is that my seating position is limited, due to screen size and the fact it has been very difficult to get this response from my sub, every sub/seating position had major dips apart from this one which to me, looks like I have got it inbetween the target +5/-5db range up until the 120hz, I dont think it will be possible to improve on that kind of response without an eq device?

So I am reluctant to change anything, when I move the speakers around the peaks and dips above 120hz, mainly dips, appear bigger and bigger 

Kind Regards
Marty


----------



## bpape

Just mark where you are now so you can go back to it. If the seating is limited and forcing an issue that you can't resolve by moving, the speaker position may be the best you can do.


----------



## marty1

Here we go, I measured 2 feet to my left, 2 feet in front and 2 feet to my right here is all 3 individual results and then all 3 measured:


----------



## marty1

Just so you can compare them with my main position again:


----------



## bpape

Well, after all of that, it appears to me that you were correct and you're in about the best place you can be. Not seeing any of those that are better -left and front don't have the dip at 120Hz (and/or it's moved to be either higher or lower in frequency as the graphs show). 

At this point, the 120hz really isn't all that bad and appears to be from a multi-dimensional mode. I would concentrate on getting the decay times more under control.

Bryan


----------



## marty1

bpape said:


> Well, after all of that, it appears to me that you were correct and you're in about the best place you can be. Not seeing any of those that are better -left and front don't have the dip at 120Hz (and/or it's moved to be either higher or lower in frequency as the graphs show).
> 
> At this point, the 120hz really isn't all that bad and appears to be from a multi-dimensional mode. I would concentrate on getting the decay times more under control.
> 
> Bryan


So apart from the decay time I take it this is a pretty good response that I have achieved, in other words no problems that I would really be able to notice?

Admitedly the sub isn't in the place my wife appreciates it (halfway alon the side wall), she preffered it in the front position, the response below I achieved with the sub in that position, but am I right in thinking that there will probably be an audible difference between these 2?


----------



## bpape

The 120 likely won't be too noticeable. The 190ish is pretty deep though very narrow.

The front orientation has a couple of pretty wide and deep dips that would make it sound much thinner and much less slam to it in my opinion.

Getting the decay times in line will help tighten things up and provide more apparent extension along with better dialog clarity.

Bryan


----------



## marty1

bpape said:


> The 120 likely won't be too noticeable. The 190ish is pretty deep though very narrow.
> 
> The front orientation has a couple of pretty wide and deep dips that would make it sound much thinner and much less slam to it in my opinion.
> 
> Getting the decay times in line will help tighten things up and provide more apparent extension along with better dialog clarity.
> 
> Bryan


Sorry when you say the wide dips you are talking about the response from the sub in my wifes favourite position (#125) not the one above that (#123)?


----------



## bpape

Correct - the front position that's preferred by the wife in #125


----------



## marty1

bpape said:


> Correct - the front position that's preferred by the wife in #125


Oh well, she will have to stay unhappy :devil:


Anyway she has 20 rabbits and 5 geese in our garden so it's give and take 

So i can rest easy knowing my main response is good then :T

So I take it isn't going to have much audible benefit to get an eq device then?

In regards to the reverb time I take it it is now time to start room treatment?


----------



## bpape

You can try to EQ up the 120Hz as long as it's not modal in nature. The other one, I wouldn't worry about too much. Like I said, it's pretty narrow for as high in frequency as it is. 

Treatment is definitely the way to address decay times, reflections, etc.

Bryan


----------



## marty1

bpape said:


> You can try to EQ up the 120Hz as long as it's not modal in nature. The other one, I wouldn't worry about too much. Like I said, it's pretty narrow for as high in frequency as it is.
> 
> Treatment is definitely the way to address decay times, reflections, etc.
> 
> Bryan


I figured the bare wall behind me should be my first port of call, with some diffuser panels spread out across it, I can't afford to do the lot yet so I'm prioritising, would this be the best place to begin?

Also am I best to leave the front mains where they are, about 2 inches from front wall?


----------



## bpape

If that close to the wall is the best response, then I'd leave them there. Not optimal but there are always tradeoffs. Eventually, you'll want to address those close walls with something absorptive to catch the very early reflections.

Broadband bass control is usually the best place to start. Having the speakers that close to a corner limits that location though. Next best spots would be front wall/floor junction if there is space, over your head if the ceiling is 8' or less, and center of the rear wall.

Diffusion is definitely secondary as it won't do anything for decay time control and certainly won't get down into the bass range which is what we're concerned about.

Bryan


----------



## marty1

bpape said:


> If that close to the wall is the best response, then I'd leave them there. Not optimal but there are always tradeoffs. Eventually, you'll want to address those close walls with something absorptive to catch the very early reflections.
> 
> Broadband bass control is usually the best place to start. Having the speakers that close to a corner limits that location though. Next best spots would be front wall/floor junction if there is space, over your head if the ceiling is 8' or less, and center of the rear wall.


Thanks Bryan :T

So a bass trap panel behind each speaker on the front wall? How high?

Is there a possibility that they might improve the dips? Even if they force the speakers to be moved forward a bit?

Over my head, that's a new one on me. My ceiling is 8.5 feet high but above me I have the pj and the underneath of the hallway stairs protruding into the room?

So if my rear wall is 13ft wide by 8.5ft high how big and what type of absorber do you mean to go in the centre of the wall?


----------



## bpape

There is a chance that bass absorbers behind the speakers will help. My guess is not in your case but you can certainly try whatever you get for the back wall there as an experiment.

Ideally, front corners would go floor to ceiling.

Rear wall - 4-6" thickness - 3 2'x4' panels would be good.

Ceiling - at 8.5', likely it's not going to be a big problem with height modes so you can skip those.

Bryan


----------



## marty1

bpape said:


> There is a chance that bass absorbers behind the speakers will help. My guess is not in your case but you can certainly try whatever you get for the back wall there as an experiment.
> 
> Ideally, front corners would go floor to ceiling.
> 
> Rear wall - 4-6" thickness - 3 2'x4' panels would be good.
> 
> Ceiling - at 8.5', likely it's not going to be a big problem with height modes so you can skip those.
> 
> Bryan


I was always under the impression that rear wall should be diffuse not absorb?

How far apart should these absorbers be?


----------



## bpape

There is a lot of misinformation out there. There is no one right answer that works for every room. Diffusion can work IF you don't need to address bass issues from that location, you can get enough other bass control in other places, and you can sit far enough away to make diffusion work properly. Diffusion that will work down to 300ish Hz requires for the most part that you sit a minimum of 5-6' away from it.


----------



## marty1

bpape said:


> There is a lot of misinformation out there. There is no one right answer that works for every room. Diffusion can work IF you don't need to address bass issues from that location, you can get enough other bass control in other places, and you can sit far enough away to make diffusion work properly. Diffusion that will work down to 300ish Hz requires for the most part that you sit a minimum of 5-6' away from it.


I sit 3 feet from the rear wall and I have bipoles to my left and right that I would have thought needed to use the reflections off the back wall, I would have thought the absorbers would stop the full effect?

If that isn't the case and I should try absorbers how far apart would I need to place them?

Also for the front corners, so I don't have to move these speakers too much, would 2 bass traps in each corner work, 1 on front wall and 1 on side wall, basically forming an L shape around each speaker, if that would work would they still need to go floor to ceiling?

Marty


----------



## bpape

Having the bass absorbers flat on the walls will limit how low they will reach. It will also require double the expense to cover floor to ceiling. It's doable, just not optimal.

On the rear, the dipoles are higher up. The absorbers would go from say 2' to 6' off the floor so the upper area where a lot of the reflections are is still open and could use diffusion.

Bryan


----------



## marty1

bpape said:


> Having the bass absorbers flat on the walls will limit how low they will reach. It will also require double the expense to cover floor to ceiling. It's doable, just not optimal.
> 
> On the rear, the dipoles are higher up. The absorbers would go from say 2' to 6' off the floor so the upper area where a lot of the reflections are is still open and could use diffusion.
> 
> Bryan


Ok I will stick to the corner fitting bass traps, there are quite a lot of varieties with different frequency range absorbtion, is there anything in particular I should aim for?


The bipoles are 5 feet from the floor and if I put absorbers 2 feet from the floor it would mean that a part of the absorber will go down behind the couch?

Thanks
Marty


----------



## bpape

Part of the rear wall absorbers will go behind the couch. That's fine. Bass is still going through the couch - trust me. 

For the corners, look for something that reaches as low as possible and preferably takes up as little space as possible to minimize interference with speaker/sub positioning. As an example, if you look at our 244 panel vs our Tri Trap - the Tri Trap extends out 17" from the corners. The 244's REAR will hit the wall at 17" and then stick out another 5" from there at 45 degrees. Performance still goes to the Tri Trap though.


----------



## marty1

bpape said:


> Part of the rear wall absorbers will go behind the couch. That's fine. Bass is still going through the couch - trust me.
> 
> For the corners, look for something that reaches as low as possible and preferably takes up as little space as possible to minimize interference with speaker/sub positioning. As an example, if you look at our 244 panel vs our Tri Trap - the Tri Trap extends out 17" from the corners. The 244's REAR will hit the wall at 17" and then stick out another 5" from there at 45 degrees. Performance still goes to the Tri Trap though.


How far apart do the absorbers go on the rear wall and eventually would I need diffusers on the rear wall either side of the absorbers?

With all the help you have given me Bryan I would really love to give you the business and order the absorbers from yourself but I get the feeling it will cost a lot to ship over? The quote I got for 3 curved 4' X 2' diffuser panels with nice matching to room colour fabric was nearly £600 and that company was over here in the UK.

Kind Regards
Marty


----------



## bpape

Hi Marty

First, I'm here to help everyone whether they buy from us or not. I do appreciate the thought though. That said, we do have a factory in the UK so it doesn't need to be shipped from the U.S.

I would likely space the thick panels 4-6" apart to take advantage of the perimeter (assuming our products) being open to absorption but not so far that you start to get a lot of reflections. You don't necessarily NEED to do diffusion but it's certainly an option. Probably 90+% of the home theaters out there don't have any diffusion.

Bryan


----------



## marty1

bpape said:


> Hi Marty
> 
> First, I'm here to help everyone whether they buy from us or not. I do appreciate the thought though. That said, we do have a factory in the UK so it doesn't need to be shipped from the U.S.
> 
> I would likely space the thick panels 4-6" apart to take advantage of the perimeter (assuming our products) being open to absorption but not so far that you start to get a lot of reflections. You don't necessarily NEED to do diffusion but it's certainly an option. Probably 90+% of the home theaters out there don't have any diffusion.
> 
> Bryan


I appreciate your help Bryan and didn't think it was about financial gain I just wanted to offer you the business since you have commited quite a bit of time to my thread :T

So to order is it just your standard website or is there a UK site to order from?

If I was to get any would the diffusers go either side of the absorbers on the rear wall, each one near the side walls and would they actually add anything to the sound quality in my size room?

Kind Regards
Marty


----------



## bpape

Diffusion can add a sense of spaciousness to the sound and make the surround field more enveloping.

If you go to our website under PRODUCTS or ORDER NOW, and just hover, you'll see that it drops down an option for US or UK websites and will take you to the appropriate page.

Bryan


----------



## marty1

bpape said:


> Diffusion can add a sense of spaciousness to the sound and make the surround field more enveloping.
> 
> If you go to our website under PRODUCTS or ORDER NOW, and just hover, you'll see that it drops down an option for US or UK websites and will take you to the appropriate page.
> 
> Bryan


Okay thanks Bryan!

In regards to the diffusers if I put the absorbers up in the mid section where would the diffusers ideally be placed or would it be a case of all absorb or all diffuse?


----------



## bpape

Best places for diffusion are usually"

- Ceiling reflections
- Rear 1/2 of the side wall
- Rear wall where you don't have bass control.


----------



## marty1

bpape said:


> Best places for diffusion are usually"
> 
> - Ceiling reflections
> - Rear 1/2 of the side wall
> - Rear wall where you don't have bass control.


Well at the moment that looks like if I do eventually get some they will go about a foot away from each corner on the rear walls, that should deal with the first reflections from the bipoles.

Thanks again Bryan :T


----------



## marty1

My wife is a bit concerned as to how these absorbers will look, the first thing is none of the fabric colours match our room decor, are there any panels you can either paint or have a wider variety of fabrics, for both the corner traps and the rear wall absorbers?

Also she thinks that 2 big panels on the rear wall that stick out 4 inches will look quite intrusive, is there something thinner that will still work well, if so what panels can you recommend for rear wall and for front corners?

I know ideally the thicker the better, I do want to make sure that if I pay out for all these panels that the performance has a noticeable difference, but If I can get somewhere in the middle so that the panels blend in with the decor and improves the performance then that would be great.

Would appreciate your advice please Bryan.


----------



## bpape

We can do a variety of custom fabrics. Cost is a fraction higher but not a lot. We just don't get as good a price when not buying full bolts. Go go the Guilford of Maine website and go to the sample center. Look at any of the FR701-2100 series fabrics.

On the rear wall, unfortunately not. The idea on the rear is to address bottom end cancellations. That simply requires thickness. Ideally, we'd go with the 7" panels so the mid size ones are already the compromise down in thickness.


----------



## marty1

When you say bottom end cancellations, do you mean like the ones I have above 120hz, is there a level of thickness that treats certain hz levels, like 50mm-treats down to 200hz, 100mm down to 150hz, something like that? Just wondering as below 120hz I dont really have any cancellations, so may not need to go as thick, if that is the case.

So I take it 50mm rockwool would have very little effect?

What panels do you recommend for the front corners and for the rear wall, the rear wall is dot and dab that crumbles, I take it 4 inch panels will be too heavy for wall mounts?


----------



## bpape

Generally, to reach into the deeper bass, you're looking at 100mm or more thickness. How low is kind of a variable question as it depends on the angles of incidence. Not sure what dot and dab is - sorry.


----------



## marty1

bpape said:


> Generally, to reach into the deeper bass, you're looking at 100mm or more thickness. How low is kind of a variable question as it depends on the angles of incidence. Not sure what dot and dab is - sorry.


Dot and dab is the cheaper way of putting up plasterboard, when I drill into it it crumbles quite easily so I was a bit worried that a 4inch thick panel might be a bit too heavy.


----------



## bpape

Sorry - been buried. If it's plasterboard, it should still be fine. 90% of the force from hanging will be vertical and perpendicular to the adhesive.

Bryan


----------



## marty1

bpape said:


> Sorry - been buried. If it's plasterboard, it should still be fine. 90% of the force from hanging will be vertical and perpendicular to the adhesive.
> 
> Bryan


Thats great, I have ordered some fabric samples to look at from Guildford of maine website, which sound absorbers do you recommend for rear wall and which ones for the front corners?


----------



## bpape

Tri Traps are the best combination of bass extension while taking up the least space. 

Rear wall - Monster panels would be best but seeing as how you're concerned about weight, you may need to stick with 244's.

Bryan


----------



## marty1

Okay that great thanks Bryan :T

Do those tri traps come in any other colours beside from the 5 on offer? Even if they are paintable as it's quite an unusual purple colour our walls our coloured with?

Kind Regards
Marty


----------



## bpape

We offer the Guilford fabrics at a slight upcharge. There is a purpleish one available and other custom Guilford colors available. Painting is pretty much a no-no. You'd plug up the pores and completely change how the treatment operated.

The only option would be to get it in off white and paint with WATER COLOR paint. Can't make any guarantees as to how it would come out though.

Bryan


----------



## marty1

bpape said:


> We offer the Guilford fabrics at a slight upcharge. There is a purpleish one available and other custom Guilford colors available. Painting is pretty much a no-no. You'd plug up the pores and completely change how the treatment operated.
> 
> The only option would be to get it in off white and paint with WATER COLOR paint. Can't make any guarantees as to how it would come out though.
> 
> Bryan


I received the fabric samples today, I have 2 that pretty much fit in, I'd be happy to pay the extra.

Can you offer me your thoughts on the question in my last post please Bryan, in regards to the kit compared to buying the bits individually, as it may work out cheaper in the long run?

Marty


----------



## bpape

Really not much difference in price quite honestly. Most times, you're better off to buy exactly what you need vs trying to shoehorn a kit to fit - unless it's exactly what you need and then add bits as required.

Bryan


----------



## marty1

bpape said:


> Really not much difference in price quite honestly. Most times, you're better off to buy exactly what you need vs trying to shoehorn a kit to fit - unless it's exactly what you need and then add bits as required.
> 
> Bryan


Okay Thanks again :T

Marty


----------



## marty1

The other thing I needed to address is the bare wall on the left hand side of my room, the wall on my right hand side has a window and a door with a window, both are covered by big blackout curtains that go near enough floor to ceiling and pretty much the entire wall.

Curtains opposite is definately a nono, even the wife said she would prefer fabric panels, even if we could do a printed fabric and make them look like pictures on the wall, what would my options be for this bare wall to balance out the sound?

Also I just wanted to double check something again, all the treatment packs show just 1 trap in each corner of the room and just 1 monster trap in the centre of the rear wall, you did say it is better to have 2 tritraps in each cornergoing from floor to ceiling and have 2 monster traps on the rear wall (or if concerned about the weight 2 244's)?

The main reason I ask is If it is just as effective to have 1 in each corner and just 1 monster trap on rear wall then the treatment pack will probably work out cheaper as it pretty much has everything I need apart from the selected fabrics.

Marty


----------



## bpape

The kits are just general layouts and an easy way for people to order a group of things with one item designation. Personally, I prefer to have stacked bass absorbers in the front corners and multiple panels on the rear wall for better coverage based on the size of the waves we're trying to address.

You can certainly do Art Panels on the wall opposite the curtains to balance out the absorption and look nice at the same time.

Bryan


----------



## marty1

bpape said:


> You can certainly do Art Panels on the wall opposite the curtains to balance out the absorption and look nice at the same time.
> 
> Bryan


What model absorber will I need, I would have thought they need to be quite thin to correctly balance the sound with the type of absorbtion the curtain is creating, or does that not matter too much?

Marty


----------



## bpape

The thinnest (and standard for Art Panels) is the 242. We're not going to be able to get it perfectly balanced but this will at least address the off axis upper mid and high frequency reflections on both sides. 

Bryan


----------



## marty1

bpape said:


> The thinnest (and standard for Art Panels) is the 242. We're not going to be able to get it perfectly balanced but this will at least address the off axis upper mid and high frequency reflections on both sides.
> 
> Bryan


So I was correct in thinking the thinner the better in this case?

Marty


----------



## bpape

242's are appropriate. Don't want to go too thin and only worsen the imbalance by absorbing more high frequencies only.


----------



## marty1

bpape said:


> 242's are appropriate. Don't want to go too thin and only worsen the imbalance by absorbing more high frequencies only.


I am guessing that I would need 3 panels 4'X2' placed the same height as the rear absorbers, about 2 feet from the floor, which would pretty much cover most of the bare wall?


----------



## bpape

You'd want something to cover roughly what's covered on the other side so depending on that, 2-3 panels.

Bryan


----------



## marty1

bpape said:


> You'd want something to cover roughly what's covered on the other side so depending on that, 2-3 panels.
> 
> Bryan


Thanks :T


----------



## marty1

I received the FR fabric samples from Guildford of Maine, there are 2 that are close but not quite the right shades, are there any other fabrics ranges from them that can be used on sound absorbers at all?

Prefferably plain (no patterns) like the FR range and good to look at.

Marty


----------



## bpape

We can use any of the Guilford fabrics you want. I would not recommend any that are classified as upholstry though. Price per yard varies wildly so I'd have to get an exact price once you pick something.

Bryan


----------



## marty1

Great, hopefully that would give me more options now, I have asked for samples from the anchorage range and anything that has purples or greys and is not classified as upholstry.

Marty


----------



## marty1

Hi Bryan,

Well the panels are up and looking great, Thanks :T

It definately sounds softer with more clarity, they have a very impressive look to them, especially the Art Panels. I just hope I haven't over absorbed as it is pretty much all absorbers and curtains all the way round the room?

Okay I've measured again but I am not sure what I am looking at in terms of improvements, can you have a look for me please?

I have posted with and without amps mcaac eq on, the reason is that the response looks flatter without it on but I always try to leave eq on regardless as I am not sure how many other things it fine tunes that I have no idea about and that maybe REW cannot show?? I have also put waterfall before room treatment.

Kind Regards
Marty


----------



## bpape

Decay times are certainly better. If you're measuring at just the main seat, it could well be that the EQ is actually making the response a bit worse and it's trying to measure and compensate for a variety of locations. There are still some things to address in the space.

Curtains will absorb a LOT of high frequency only information which is likely a portion of the softness.

Bryan


----------



## marty1

bpape said:


> Decay times are certainly better. If you're measuring at just the main seat, it could well be that the EQ is actually making the response a bit worse and it's trying to measure and compensate for a variety of locations. There are still some things to address in the space.
> 
> Curtains will absorb a LOT of high frequency only information which is likely a portion of the softness.
> 
> Bryan


Do I leave the eq off in that case?

What is the next step in terms of improvements, do I need to add diffusion and any more absorbtion?

I still appear to have that huge dip inbetween the 100-200hz zone.


----------



## bpape

The thread is getting pretty long. Any chance of a sketch of the room again with the treatments you've installed, listening position, etc. marked?

Bryan


----------



## marty1

I am not sure how to draw diagram but here is a full 360 view, starting at seating position looking at screen.

The last picture I put in for good measure, it is just to left of the main seating position and it is where the stairs from the hallway partially comes across the corner of the room.

There is still a tiny bit of echoe in the room but hardly noticeable. Not sure how much effect that is having on the sound?

There are 4 tritraps in the front corners, 2 monster traps behind the couch, 3 art panels on the left wall, nothing on the ceiling and curtains all along the right hand side of the room.

Kind Regards

Marty

It isn't uploading pictures so I will pm them to you if that is ok


----------



## marty1

How do I put the pictures on? I changed the pixels 1000x750 but it still keeps coming up the file is too big?


----------



## Gregr

Hey Marty,

How are you uploading your pics? 

Greg


----------



## marty1

I import the pics from my camera onto my laptop, then on the reply I click attachments, browse, click on the selected pics and the upload. First it came up file is too big, so I went onto the pics, click edit then changed the pixel size to 1000 x 750, resave it then tried again but it still came up file is too big?


----------



## Moonfly

Make sure your picture is a jpg rather than bmp file, they have a larger size cap. Then just dowload pix resizer to scale your images if you need to do that.


----------



## marty1

Okay here goes, figured it out thanks 

So what can I do to improve this waterfall, especially that big dip between 100-200hz?

There is still a little bit of echo but not much.

I was thinking maybe 1 more monster trap turned sideways behind the centre speaker (or would a smaller one be better, a gik 242 or something), then maybe a 242 size panle turned sideways on the bare wall to the left of the front left main speaker. Finally some diffusers on the back wall either side of the monster traps and some diffusers on the ceiling. Not just to improve the REW measurements, but to overall tighten up and perfect the sound quality.

Or would this be overkill :huh:

Regards
Marty


----------



## Gregr

Marty1,
After uploading to your laptop the image should upload in any size format but 800x600 is still plenty big to fill a TV screen with enough detail to see what your watching for a movie in your theater photos. 

But before you can add a pic to your posts/replies you need to download images to your "Image Gallery"...:

Go to your profile an click on "Image Gallery Tab" then simply follow instructions on uploading. At the bottom of the page are instructions on adding pics to your Posts/Replies.

That should do it 

Greg


----------



## Gregr

Better late then never

Greg


----------



## marty1

Gregr said:


> Better late then never
> 
> Greg


Ha, did I do something wrong or did you reply before seeing the previous post?


----------



## Gregr

Marty,

Your all set. I loaded a bookmarked page and needed to reload the page. All I saw was a question.
Looks like you've had allot of help setting up your sound. Nice setup..., love Focal

Greg


----------



## marty1

Gregr said:


> Marty,
> 
> Your all set. I loaded a bookmarked page and needed to reload the page. All I saw was a question.
> Looks like you've had allot of help setting up your sound. Nice setup..., love Focal
> 
> Greg


Thanks :T

I love the Focal Profiles sound, they have so much clarity compared to anything I have heard, match them with the PB13U and it's awesome. 

Yeah I have had a lot of help from various people, especially Bryan, great advice that has truely added a lot more to my HT experience.

I just have to figure out how to get rid of that big dip and see if a bit of diffusion will add anything noticeable to the performance.

Marty


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## Moonfly

That big dip is only really gonna be filled out by either moving the sub or getting a second and placing it somewhere that fills the dip in. At some point your going to have to settle for the graph as it is and decide if your happy with the sound. You can do a lot to a room to optimise it, but there is a limit to everything unless you build the room from the ground up.


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## marty1

Moonfly said:


> That big dip is only really gonna be filled out by either moving the sub or getting a second and placing it somewhere that fills the dip in. At some point your going to have to settle for the graph as it is and decide if your happy with the sound. You can do a lot to a room to optimise it, but there is a limit to everything unless you build the room from the ground up.


Don't get me wrong, the sound is fantastic and I am content with it, I just enjoy trying to perfect things here and there. The acoustic panels have had a night and day impact on the sound, not so much with the graph though but more to my ears. I still have a very tiny bit of echo when I clap but I am contemplating covering first reflections on the ceiling with diffuser panels at some point, so that may tighten things up a bit more.


I am certain that dip is the front left speaker, when I measure the sub with xo at 80hz it litterally peters out just after that mark. When I measured individual speakers without the sub on, the front left speaker was almost ruler flat but the front right speaker was all over the place, I think that dip was there?

Marty


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