# First time user - mixed results



## lovingdvd (Jan 23, 2007)

Hello - well I got all the pieces in place and go up and running quite smoothly with REW. What a fantastic product! Hats off to all those that contribute to its development and support. The help files are exceptional and it made for a very smooth setup and configuration.

Its late so I'll spare some detail for now, but I had some mixed results so I'd like to please get some clarifications:

I measured for only the sub. Target was 75dB, xo 80hz. I used the Find Peaks and Optimize very easily and it flattened out a good bit of the major peak issue I was having!

However I am unclear what to do about the dips. For instance I have a dip at 60hz. I was able to clear it up by using +6dB gain 4 wide. The curve now looks nice. However I am concerned about headroom and clipping issues because the manual says not to go over 3dB gain for filling in dips.

I play my system at fairly low levels most of the time, and only occassionally start to crank it up. But even in those cases I never really blast it. Point is that I know the sub can play and handle much larger volumes than I ever push to it. So in that case am I safe using this level of gain?

The other question I had is that I wound up using all 12 filters because I had various small gaps to lower (about -2 to -5dB) and a handful of dips to raise (+3 or so except for that one +6 I already mentioned). This made for a rather choppy line (all +/- about 2-3dB from 75db).

Is there a way I could have it smooth this out? I used the Optimize function but apparently that only smooths out the AUTO filters, whereas these I added were manual. Is there a way I can tell REW 'hey these are filters I want you to consider in your optimization' and have it smooth over my manual ones as well? If not how does once achieve a more smooth curve if they have several small dips and peaks to manually take care of?

OK so after doing just the sub I turned my attention to calibrating with the L/R fronts added in and set to full range Full Range. This is where things went down hill.

In this mode I had a very choppy spikes for dips and peaks from 30-100hz (and up). Lots of zig-zags. I don't know how to begin to smooth that over. It took out some peaks but I'm left with a ton of big dips. When I measured my L/R along without the subs and choose Base Limited I saw that these speakers contribute a lot of bass (as they should - they are rated down to 32hz). I am really surprised to hear just how much bass is coming out of these speakers below the 80hz crossover, and I verified that my Yamaha receiver is set to xo at 80hz.

I'm tempted to just equalize the sub alone knowing that it will be smooth and not worry about how the sub and fronts do together. However I have a feeling that is the wrong approach.

Also as a side note - what is one supposed to do if they have a significant dip. Everything I read says don't crank up the gain too much. But say someone has a -10dB dip? I'm thinking that in this case you can define the target -10dB lower, and then flatten everything else out. Then just crank up the sub to get it balanced with the rest of the system again. But not sure if that is the right approach.

For instance in my case where I had that -6dB dip, is there an easy way to take out 6dB from everything else and then not have to raise the dip? I'm very confused about this.

Thanks again!


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## lovingdvd (Jan 23, 2007)

BTW - I just wanted to add that I have not yet tried any of the EQ filters in the BFD - just working within the REW software and its estimated results. Perhaps actual results will be close but a bit smoother and these little dips/peaks I referred to in my last post will be smoothed. 

At any rate I plan to get these programmed into the BFD tomorrow. Because the MIDI doesn't work I didn't have a chance to program it in yet, as I'll need to research how to do that tomorrow.


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## terry j (Jul 31, 2006)

"For instance in my case where I had that -6dB dip, is there an easy way to take out 6dB from everything else and then not have to raise the dip? I'm very confused about this."

For sure, boosting the entire response by 6db then cutting everything else back around the dip is a totally valid and workable way to go, and is usually the way I do it. Of course that only applies to the sub, guess it's a bit trickier if it's the mains that are causing it!

You didn't mention how 'sharp' the dips were, the sharper they are the less you need to worry about them.

In any case, more intelligent help is probably on it's way!! ha ha. Just as an afterthought, always test the results of any boost you do, if it doesn't respond to the boost then get rid of it quick as it's likely that no amount of boost will help in that situation.

As always, trust your ears and if it doesn't sound like it is struggling then it is probably OK.


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## Ivaols (Dec 29, 2006)

lovingdvd said:


> OK so after doing just the sub I turned my attention to calibrating with the L/R fronts added in and set to full range Full Range. This is where things went down hill.
> 
> I'm tempted to just equalize the sub alone knowing that it will be smooth and not worry about how the sub and fronts do together. However I have a feeling that is the wrong approach.
> 
> Thanks again!


Hi,

1: try setting the L/R fronts to NOT play anything under 80 HZ. This will give your speakers and your receiver more headroom, and will probably remove a lot of the (gain/phase) problems below 80hz. 

2: Your feeling is correct, after all you do listen to front speakers and sub at the same time.


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## lovingdvd (Jan 23, 2007)

terry j said:


> For sure, boosting the entire response by 6db then cutting everything else back around the dip is a totally valid and workable way to go, and is usually the way I do it. Of course that only applies to the sub, guess it's a bit trickier if it's the mains that are causing it!


Mainly concerned with just the sub at the moment. How do I go about boosting the entire repsonse by 6dB and then cutting everything else back? Do I simply turn up the sub? Will REW then take care of the filters to flatten everything back to the target? I ask because this will not really be a peak for much of the range - instead it'll be a range that's about 6dB too high. 



> You didn't mention how 'sharp' the dips were, the sharper they are the less you need to worry about them.


Pretty sharp, like zig-zags.



> In any case, more intelligent help is probably on it's way!! ha ha.


Thanks I look forward to hearing from the guys on all this but certainly your input has been very helpful too!


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## lovingdvd (Jan 23, 2007)

Ivaols said:


> Hi,
> 
> 1: try setting the L/R fronts to NOT play anything under 80 HZ. This will give your speakers and your receiver more headroom, and will probably remove a lot of the (gain/phase) problems below 80hz.


Is this a common feature in receivers? I don't think there is any way I can tell my Yamaha RX-V1400 to not play anything below a certain freq like 80hz. I have them set to Small, and have the xo at 80hz, but it would be great to have it cut the lows off sharper if anything.

It does have an EQ that I could probably use to set 60hz very low and maybe 80hz too. But if I engage its graphic EQ then I cannot use its parametric EQ auto-calibration, and I need that for it to balance the high end (unrelated to the sub).


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## lovingdvd (Jan 23, 2007)

*Challenges with line input level*

Here's an oddity I was also hitting I'd like some feedback on...

When I did the Check Levels from the Sound card options it said my input level was good like -18dB. However when I press the Check Levels button on the Measurement window before taking a measurement it said it was too low, like -30ish.

So I then used the option to increase the level from -12 to -9. Then the measurement Check Levels button said the level was ok. But then the problem was that my receiver was no longer putting out 75dB, it was putting out something more.

So then I'd lower the receiver volume so I was back to 75dB, but then the Measurement Check Levels button again would say it was too low. So I was caught in this cycle.

Eventually somehow or another I seemed to manage to get this straight while using the -12 setting. Not sure how I did this though and am wondering what to do the next time this happens. Thanks.


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## brucek (Apr 11, 2006)

> Mainly concerned with just the sub at the moment. How do I go about boosting the entire repsonse by 6dB and then cutting everything else back? Do I simply turn up the sub?


Yes, but the sub has to have that headroom. You'd be far better to post your graph so we can see it.



> Is this a common feature in receivers? I don't think there is any way I can tell my Yamaha RX-V1400 to not play anything below a certain freq like 80hz. I have them set to Small, and have the xo at 80hz, but it would be great to have it cut the lows off sharper if anything.


Yes, most receivers allow a different crossover than 80Hz. If yours is fixed at 80Hz that is fine.




> Is there a way I could have it smooth this out? I used the Optimize function but apparently that only smooths out the AUTO filters, whereas these I added were manual. Is there a way I can tell REW 'hey these are filters I want you to consider in your optimization' and have it smooth over my manual ones as well? If not how does once achieve a more smooth curve if they have several small dips and peaks to manually take care of?


REW does what you ask. The Help file says:

"The filter settings can be manually adjusted to improve the correction, typically adjusting the Q values and using Adjust PK Gains to readjust the gains to suit. The graph traces update as the adjustments are made making the process fast and easy. Adjust PK Gains alters the gains of all Automatic filters to bring the response at their centre frequencies to the target level. Q is not altered."

So simply set a filter to MANual if you don't want it included or set it to AUTOmatic if you do want it included.









brucek


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## lovingdvd (Jan 23, 2007)

brucek said:


> Yes, but the sub has to have that headroom. You'd be far better to post your graph so we can see it.


Is it possible to post the mdat file so you can see everything including the filters?



> Yes, most receivers allow a different crossover than 80Hz. If yours is fixed at 80Hz that is fine.


Mine definitely has variable xo. For instance I can move it up from 80hz, to say 90hz, 100hz, 110hz etc. I thought what Ivaols was saying was to set things so it does not play anything at all below the xo. Because of the slope that would mean setting the xo quite high. I'd like to get the xo point as high as possible. But my concern is localization of the sub. If I start sending say 90hz or more to the sub won't I risk localization?




> REW does what you ask. The Help file says:
> 
> "The filter settings can be manually adjusted to improve the correction, typically adjusting the Q values and using Adjust PK Gains to readjust the gains to suit. The graph traces update as the adjustments are made making the process fast and easy. Adjust PK Gains alters the gains of all Automatic filters to bring the response at their centre frequencies to the target level. Q is not altered."
> 
> ...


Yes I had read that and tried setting mine to AUTO. However when I told it to optimize things after I added my manual one in it REMOVED all my manual entries. So I figured that in order for the entries to "stick" manual entries must be set as Manual. Obviously I am missing something here? Thanks!


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## brucek (Apr 11, 2006)

> But my concern is localization of the sub. If I start sending say 90hz or more to the sub won't I risk localization?


Yes, leave it at 80Hz. You took what Ivaols said too literal. He meant set the xo at 80Hz.



> Is it possible to post the mdat file so you can see everything including the filters?


Yea, you can just attach an mdat file just like you attach a pic. I'd rather see the pic too...



> Obviously I am missing something here? Thanks!


Just play around. You'll get it..

brucek


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## lovingdvd (Jan 23, 2007)

brucek said:


> Yea, you can just attach an mdat file just like you attach a pic. I'd rather see the pic too...
> brucek


Thanks. I've attached the files. Note that although the file type is .mdat, these are really .zip files of the .mdat. So after you download them please rename them from .mdat to .zip. I had to do this because the mdat files were about 780KB each so the forum wouldn't accept them because they were over 750kb.

I was under the impression that this file is mainly a project file and that once loaded you'll be able to see the graphs and recommended EQ settings and so forth. No? If not let me know what graph you want me to produce and I'll follow the guidelines for posting it.

Also when you have a chance please let me know about the auto vs. manual EQ filters question I have. In my last post I mentioned that when I set the filters I added with Auto and tell REW to optimize, REW removes my filters. This is why I did them as manual but would prefer it to take my "auto" as hints and do a better job with the EQ than I can do manually. Thanks again!


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## brucek (Apr 11, 2006)

> I was under the impression that this file is mainly a project file and that once loaded you'll be able to see the graphs and recommended EQ settings and so forth. No?


Well yeah, but that's kinda time consuming. I would rather you press the 'save as jpg' button on the REW graph and post it as an image as I've done below - then everyone can discuss....

Anyway, your response of the sub is easily BFD'd. I attached a quick set of filters where I only added one more than REW recommended and then optimized. Simply don't use manual. Make all filters AUTO. It works fine. You could just enter the filters I show into the BFD and it would clear up a lot, but it's better you play with it yourself. I attached the before and after picture of your sub.

The mains plus sub is another story. I don't see how that is your mains and sub together. It looks more like the mains only. If it's the mains plus sub, then where did the sub go. Look at the sub only and see what I mean. You'll have to sort that out.


SUB ONLY RAW MEASURE










FILTERED SUB









SUB + MAINS (I don't really think so??)










brucek


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## lovingdvd (Jan 23, 2007)

brucek said:


> Well yeah, but that's kinda time consuming. I would rather you press the 'save as jpg' button on the REW graph and post it as an image as I've done below - then everyone can discuss....


Makes sense - will do that in the future.



> Anyway, your response of the sub is easily BFD'd. I attached a quick set of filters where I only added one more than REW recommended and then optimized. Simply don't use manual. Make all filters AUTO. It works fine.


I'm still confused about the Auto filters. I'll play with it some more and see what I can figure out. Perhaps I am not following the procedure correctly? Any idea what issue I may have been hitting where I was adding Auto filters, then telling it to optimize, and it was removing my filters I added?

What about the dip at 53hz? Should I add a manual filter to try bringing that up a few dB? Same for the smaller dips and peaks? For instance is it helpful at 20hz, 31hz and 37hz to add a narrow filter to bring these down a few dB? And perhaps push up 72hz a couple dB? I recall seeing graphs you've posted of your HSU and the line looks perfectly smooth around the target. Then again you are the master! 



> The mains plus sub is another story.
> brucek


Yea I'm not sure what happened there. I was playing with lots of things back and forth and it was late. That likely was mains only. I'll work that out.

My plan from here is to first get the bass only equalized. Then I'll add the mains back in and see what it all measures together. From there I'll tweak it some more. Too bad I don't have any EQ control over the fronts for its bass. I could get limited control via its graphic EQ but then I'd lose its parametric EQ functions which I need for the high end.


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## JohnM (Apr 11, 2006)

*Re: Challenges with line input level*



lovingdvd said:


> Here's an oddity I was also hitting I'd like some feedback on...
> 
> When I did the Check Levels from the Sound card options it said my input level was good like -18dB. However when I press the Check Levels button on the Measurement window before taking a measurement it said it was too low, like -30ish.
> 
> ...


What end frequency were you using? The levels check in the measurement window tests across the whole range you are set to measure, when measuring a sub that means the result gets lower as the end frequency goes higher. It operates differently to the levels setting on the soundcard settings to avoid having to select whether you using a sub or a main speaker (Bruce told me this would confuse people :R)


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## brucek (Apr 11, 2006)

> What about the dip at 53hz? Should I add a manual filter to try bringing that up a few dB? Same for the smaller dips and peaks? For instance is it helpful at 20hz, 31hz and 37hz to add a narrow filter to bring these down a few dB? And perhaps push up 72hz a couple dB?


A dB here or there isn't going to really matter. The fact is, if you move your microphone a few feet you can easily have a different spot where the response will move a few dB. The really important part is removing the large peaks that occur at room resonances. Yours was at 30Hz. That's taken care of. The rest is window dressing for people who like to push buttons - of which I am a charter member. 

brucek


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## brucek (Apr 11, 2006)

> What end frequency were you using?


Yeah, I was going to answer that question John........just ran out of time.

He had an end frequency that was too high.....









lovingdvd, change your sweep range to have an end frquency of 200Hz in the Measurment panel pulldown...

brucek


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## lovingdvd (Jan 23, 2007)

brucek said:


> Yeah, I was going to answer that question John........just ran out of time.
> 
> He had an end frequency that was too high.....
> 
> ...


Roger that - will do. This is to take care of the input level warning?


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## brucek (Apr 11, 2006)

> This is to take care of the input level warning?


Yes...........


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## lovingdvd (Jan 23, 2007)

Great. Tonight I'll do some more experimenting and will put the filters into the BFD. Looking forward to hearing my sub with a flat response (the peaks I have really make it sound pretty lousy as-is) and then I'll play with the house curve. I'll report back on how it goes. Thanks again for all the help.


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## cyberbri (Apr 27, 2006)

You should DEFINITELY think about adding some bass traps to your room. Not only will it smooth out the response, it gets rid of a lot of ringing and boominess. You may not even notice any, but once you hear how your sub sounds without that nastiness, you'll never go back.

For example, here's how my in-room response looks (sub+mains) with a few bass traps:









I was able to smooth it out to this with these filters:

Freq BW Cut/Gain
74Hz 6 -13
45Hz 8 -7
66Hz 2 -4
54Hz 8 +4
37Hz 4 +4
53Hz 3 +2










Before I was using a ton of filters, 11-12, including a lot more boosts. I had similar results, but I like using less filters this way. Plus, with all the cuts I was using in the BFD, I had to turn the gain on the sub up a lot more - to 55-60% or so. There was a slight hum (presumably from the BFD and the extra connections), although it was only audible with no sound in the room and if I was within 4' from the sub. Being able to turn the gain on the sub down and just amplify a higher signal really toned down the hum as well. 

It takes a lot of experimenting. I've probably "redone" my filters 5~6 times now. Now I'm really satisfied with my results and I probably will leave them like this for a long time. With bass traps first, then with the BFD, listening to the "it's cold in here" scene from The Haunting went from "scared, but for the safety of my sub," to controlled, tight bass, hearing every detail and knock and rumble and texture. :bigsmile:


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## lovingdvd (Jan 23, 2007)

Thanks for the advice. I will have to look into adding traps.

You mention using cuts and it brings me back to something I don't think I got answered yet. Looking at the second chart shown in the post above (http://www.hometheatershack.com/forums/23231-post12.html ) let's say I didn't want to add a gain to 53hz. But rather, I wanted to cut everything down instead in order to flatten things out without having to use a gain. How does one go about such a think?


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## cyberbri (Apr 27, 2006)

First, to see if it's a dip and/or if the other frequencies are just being boosted by the room - vs it being a null, try additional sweeps to see if the volume increases/decreases the same as the rest of the graph. If it won't get any louder when you run the sweep at louder volumes, or if it only goes up a bit while the rest goes up a lot, that's tough.

But if you want to use filters to "cut" everything to the level of the lowest, do a sweep and get that lowest level around 70~75dB. Then set the "target level" to whatever dB level that range is in, and use "Find Peaks," "Add Filters," and "Optimize Filters." Be sure to check the before/after for the filters, because at least for me the end result didn't always come out like REW predicted it would. 

But don't worry about a dip that deep at 53Hz. It's probably a null if it's that deep. Aim for the level of the mid-60s there, or about 72dB on that graph. Fixing a null like that requires moving the sub and/or the couch, and bass traps could possibly help with that as well.



Also, you may find that you prefer to leave some kind of house curve on the low end, because you need more dB in the 20s and lower for it to be audible anyway. If you look at my graph:








I cut down on the rise at the bottom end, but not too much. Music won't usually dig this deep, so the impact is there for movies but it doesn't make music sound too bottom-heavy.


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## lovingdvd (Jan 23, 2007)

Thanks. My listening is almost 100% movies so I'll definitely be experimenting with house curves once I get a handle on the basic calibration.

Thanks for the tip about the dip - that's just what I'll do. I'll turn my volume up say 5dB and run the sweep again and see how much the dip comes up.

Just to make sure i have this basic principle right - it's ok to use cuts as heavy as you need (negative dBs) to get a curve with no impact (other than having to turn the sub louder). But ideally one should not add any gain beyond 3dB because doing so requires twice the power?

So in other words, everyone is in agreement that to fill a dip (assuming it is fillable and not a null) its far better to use greater cuts almost across the board, than to fill a single dip with say 6dB correct?


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## cyberbri (Apr 27, 2006)

If it's just one dip and the rest is pretty flat, try adding 3dB. A 3dB dip isn't as bad as a 6dB dip. And that would probably be easier than trying to cut every other frequency and shape it to be flat. 


But a lot depends on your "target" level, what dB you aim for when you experiment with filters in REW.

Here's a case in point, from my thread over here:
http://www.hometheatershack.com/for...digital-meter-strange-results-high-freqs.html

Here's my sub and mains, no BFD, just some bass traps:











Here's one attempt - with very good results, but using a lot of filters:









The filters I used to get there:
Freq BW Adjustment
24Hz 8 -3
30 10 -4
48.5 3 -5
40 6 -7
44.5 6 -12
53.25 3 +6
72.35 10 -16
83 6 -5
51 2 +4
89 2 +6
37.88 3 +3
100 4 -7
(some of these I added because when combined with the output of the mains I had some peaks I wanted to tame)

And here is my most recent attempt, which I think came out very well, with much fewer filters:









Filters used
Freq BW Cut/Gain
74Hz 6 -13
45Hz 8 -7
66Hz 2 -4
54Hz 8 +4
37Hz 4 +4
53Hz 3 +2

As you can see, I used cuts to bring down the big peaks, and a few small boosts to flatten it out. I could always add 3 more filters and do small 2~3dB cuts to smooth out the 60~75Hz range, but I didn't want to mess with it.

(ignore the null around 90Hz in the first and 3rd graph -- the middle/2nd graph was taken with my speakers in their original position, and after taking that I moved my speakers closer together and back a little so they're a little further away, and the 1st and 3rd graphs were taken with the new speaker position. That null is just from the sub + mains interaction. And that's why they look different above 100Hz)


One thing I didn't like about the previous attempt (2nd graph, lots of cuts) was that I had cut the levels so much I had to turn the gain on the sub way up. It was at about 55-60% and I could hear a hum coming from the sub if I got pretty close. With the most recent pass, much fewer cuts, I'm under 1/2 way on the gain on the sub. My HK receiver puts out a lot of voltage in the sub signal, so I had to turn it way down in the receiver so the signal wasn't clipping coming into the BFD. Originally, before BFD, the gain was at maybe 15% or so, or 1/2 way between 0 and the first tick on the sub gain.


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## lovingdvd (Jan 23, 2007)

Looks great! I see what you mean. Regarding my dip, take a look at the second graph in this post: http://www.hometheatershack.com/forums/23231-post12.html . Look around 53hz. That's about a good 6dB. 

That could be a null that I can do nothing about (short of room treatments). So I'll try your recommendations as far as determining whether its is treatable with equalization.

Assuming so, based on that graph would you push it up 6dB, or bring everything else down instead, or maybe just bring it up 3dB and let it be short about 3dB?


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## brucek (Apr 11, 2006)

> Regarding my dip, take a look at the second graph in this post:


If when you add your filters, and the graph and dip looks as it does in the predicted response, then it would be wise to add the mains and see if it persists..... only then do you decide on an action..

brucek


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## lovingdvd (Jan 23, 2007)

*Results from last night - and how to handle localization issues?*

Last night I had some good success with REW and BFD as I dug in and starting to dial things in nicely.

With the sub alone, I got the response to be nearly perfect! However this beautiful response curve fell apart once I added added the mains back in. So essentially at that point I had to start all over with the filtering process to account for the subs+main.

I noticed I had some dips and fall off (in a sharp-like zig-zag fashion) in the 70-90hz range. Then i dawned on me. I did not have the HSU sub's crossover OUT - I had it engaged at the maximum xo of 90hz.

I had done this previously because when watching movies I noticed some localization coming from the sub.

Interestingly, when I turned the subs xo switch to OUT, the dips were gone and in fact were a bit too high in that 70-90hz range, but I brought those down with some more filters.

So in summary with the sub's xo switched to out and my latest filters, I have things very flat at about +/- 2dB from 20-90hz with no dips or peaks whatsoever!

However... Now I noticed that I have a challenge with the localization again. My sub is only 6 feet away behind the couch and there is no other place in the room for it. I have to listen a bit more closely but I believe I am now getting muffled voices and so forth coming from the sub in this configuration.

I guess this would make sense, because with a proper rolloff one still has a fair amount of dB of 100+hz coming from the sub and its my understanding around that range is when you start to pick up localization.

What is the best thing to do if your calibration shows very good tracking to the target, but results in too much localization?

I have not yet added a house curve, which I plan to work on tonight. With the house curve I'll likely wind up with a good 5-10dB push in the 20-30 range, or more of a linear slope in which case the upper end (higher hz) will still be 5-10dB lower than 20-30hz.

So I'm thinking that this will result in me needing to turn the sub down a bit, and therefore decreasing the dB of the localization frequencies in the sub?

Another thing I am considering is just put the xo on the sub back in and leaving it at 90hz, perhaps even toning things down a bit. This will result in the bass being a bit shy in the upper end of the sub's range, but would be better I think than having localization.

Its a shame I have no way to boost the 80-100 range at the main speakers. This would allow me to use the xo switch on the sub to cut the 80-100 range back at the sub while increasing it at the receiver/mains so the net affect would still be the right amount of bass in that range.

Humm. Anyone know if I may be able to get this type of boost in the mains by just turning up the Bass knob on the receiver itself? If doing so wouldn't affect the sub than perhaps that could work?

At any rate any recommendations for how to handle this would be much appreciated. Thanks!


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## brucek (Apr 11, 2006)

> What is the best thing to do if your calibration shows very good tracking to the target, but results in too much localization?


Normally, you would just lower the crossover setting, but I believe 80 is as low as your receiver allows.



> However this beautiful response curve fell apart once I added added the mains back in.


Are you sure you don't have a setting with your mains that is adding some low end to them even though they're set to small. Many receivers have a setting such as that. Adding the mains shouldn't mess up your sub that much....



> Another thing I am considering is just put the xo on the sub back in and leaving it at 90hz


Double crossovers is not a good idea. I would scrap that notion. Let your receiver do all the bass management.

brucek


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## JohnM (Apr 11, 2006)

Try placing a manual filter in the BFD at 130Hz or so, not too narrow (BW around 8-10) and use that to lower that range until you no longer get the voices breaking through, should have less influence through the crossover region than leaving the sub's filter in place.


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## lovingdvd (Jan 23, 2007)

brucek said:


> Normally, you would just lower the crossover setting, but I believe 80 is as low as your receiver allows.


My receiver allows me to set the xo at 40hz, 60hz, 80hz, 90hz, 100hz, 110hz and some higher. Do you think it would be worthwhile to do some tests with it set at 60hz?



> Are you sure you don't have a setting with your mains that is adding some low end to them even though they're set to small. Many receivers have a setting such as that. Adding the mains shouldn't mess up your sub that much....


Thanks for the tip I'll read through the manual but I am not aware of any such setting.

I don't have the graph or data in front of me, but as I recall, when I test the mains only it shows I have about 50-60dB of bass from about 35hz and up WITHOUT the sub turned on (based on the receiver set to output 75dB). I agree is seems like a lot of influence.



> Double crossovers is not a good idea. I would scrap that notion. Let your receiver do all the bass management.


Make sense. Too bad the receiver seems to be doing a fairly poor job in this respect for some reason...


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## lovingdvd (Jan 23, 2007)

JohnM said:


> Try placing a manual filter in the BFD at 130Hz or so, not too narrow (BW around 8-10) and use that to lower that range until you no longer get the voices breaking through, should have less influence through the crossover region than leaving the sub's filter in place.


Sounds like a good idea. How is this different than, say, engaging the subs xo and having it set to its max of 90hz xo?


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## cyberbri (Apr 27, 2006)

With the xo set to OUT/on now, did you run any tests comparing the sub + mains with the sub's phase at 0 and 180 degrees? You could end up having to choose the lesser of two evils with regards to the effects, but you should at least know what the freq response is and choose what works best. 

And yes, measuring the sub alone and using cuts above 100Hz could possibly help with the problem of being able to localize of the sub.


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## lovingdvd (Jan 23, 2007)

cyberbri said:


> With the xo set to OUT/on now, did you run any tests comparing the sub + mains with the sub's phase at 0 and 180 degrees? You could end up having to choose the lesser of two evils with regards to the effects, but you should at least know what the freq response is and choose what works best.
> 
> And yes, measuring the sub alone and using cuts above 100Hz could possibly help with the problem of being able to localize of the sub.


Yes I did try with the phase at 0 vs. 180 (with the sub XO enagaged at 90; did not do this comparison with the xo OUT). After much experimentation I concluded that the phase in its normal setting (0?) was by far best. For some reason using the 180 phase resulted in a shortage of bass in the 20-30 range (which I don't understand because my mains don't go down that low anyway) and also caused some other issues like a rattle/buzz that seemed to be coming from my left front main speaker. In just listening to the sweep I could hear that it just didn't sound right.


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## lovingdvd (Jan 23, 2007)

brucek said:


> Are you sure you don't have a setting with your mains that is adding some low end to them even though they're set to small. Many receivers have a setting such as that. Adding the mains shouldn't mess up your sub that much....
> brucek


brucek - OK I think you are on to something here!! in thinking about is some more I have an idea as to what might be going on to exaggerate the low end bass from the mains...

My main speakers are within cabinets. And I know these speakers are not designed to be within an enclosure like some speakers are.

My fronts are Pinnacle Classic Gold Reference speakers. They are towers with a size of 8 3/8" Wide x 33" High x 13 1/4" Deep. Each is within an enclosed cabinet that has GOM fabric in the front. The cabinet is not much larger than the size of the speakers (cabinets are part of the wall unit these speakers sit in).

In particular I'd say that within the cabinet there is about 5-6" of space to the left/right of the speaker, about 6" of space behind the speaker, and about 8" or so above the speaker.

It seems logical that the cabinet enclosure could be having the affect of significantly boosting/amplifying the bass. So whereas before we suspected that the receiver was somehow boosting it - maybe its the enclosure. What do you think?

If it is the enclosure, I certainly cannot move the speakers but perhaps I can treat the inside of that cabinet and this would help? If so what's a good material to treat it with? Right now the inside of the cabinet is just hard wood.

Thanks!


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## brucek (Apr 11, 2006)

> It seems logical that the cabinet enclosure could be having the affect of significantly boosting/amplifying the bass. So whereas before we suspected that the receiver was somehow boosting it - maybe its the enclosure. What do you think?


Yeah, you're not suppose to do that really. The speakers should be out and away from all reflective surfaces by a few feet at least.....

brucek


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## lovingdvd (Jan 23, 2007)

brucek said:


> Yeah, you're not suppose to do that really. The speakers should be out and away from all reflective surfaces by a few feet at least.....
> 
> brucek


Thanks. Well now that I have the ability to measure actual response, as an experiment I'm going to take the speakers out of the cabinet and put them on a small table, just in front of where they were residing. Then I'll measure the response of the fronts this way vs. how they sound in the cabinet. It will be interesting to see the results.

BTW if anyone knows a good way to soundproof the inside of the cabinet to help cut down on the bass bouncing around in there please let me know (maybe some sort of insulation or something?).


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## cyberbri (Apr 27, 2006)

Warning: once you take them out of the cabinets and hear how they sound, you won't want to put them back and you'll end up doing whatever you can to keep them out.


In my last residence, we had a wall where the TV went, with the TV stand in the middle and 2 cabinets flanking it with shelves above the TV strapped to the cabinets. I didn't have room to have the speakers out, so my towers were situated in the bottom half of the cabinets. One time I took the speakers out to see how they sounded, and it was almost a night/day difference. I even sat my wife down and she was surprised - she said they sounded bigger and more open. I didn't get to keep them "out," but the next residence we moved to (our current one) has a much bigger room for me to move my speakers and sub around as I see fit.


BTW, you might see about stuffing the cabinet with towels/blankets. And do the speakers have rear ports, firing into the open cavities?


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## Guest (Jan 26, 2007)

I'm having this same problem. I'm even considering redoing my entire entertainment center because of it.


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## lovingdvd (Jan 23, 2007)

cyberbri said:


> BTW, you might see about stuffing the cabinet with towels/blankets. And do the speakers have rear ports, firing into the open cavities?


Yes, they have ports that fire into the open cavities, although keep in mind that it forms a sealed "box". In other words its not a large cavity but rather a single sealed cabinet that the speaker sits within. Perhaps this makes it even worse (since the frequency has no where to go by out).


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## cyberbri (Apr 27, 2006)

Yeah, even if it's sealed in the back, the bass will bounce around in there, and make the cabinet itself resonate at different SPLs and frequencies.


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