# REW Noob



## weverb

I am trying to start using REW. Can you please help point me in the right direction on measurments. This is the graph I am getting. What am I missing? :huh:


----------



## brucek

> What am I missing?


You're taking a measurement of your loopback cable to test your soundcard cal file, and have the SPL meter calibration file loaded. It should not be loaded when you do this test, as the result will be a perfect inversion of the SPL meter cal file....

brucek


----------



## weverb

Thanks for the help. Just had the loop back connected backwards. I feel like a .... :duh: Here are the plots. The first is just subs and the second is with the mains on.


----------



## brucek

Change your graph axis to the standard of:

Vertical = 45dB-105dB
Horizontal = 15Hz-200hz.

Anyway, it doesn't look like the first graph is a sub only through the receiver, with the crossover set, and mains disconnected (in fact, both graphs look identical). The usual starting point is to do the sub only and position it for the best response. Then add the mains and get the best crossover response.

brucek


----------



## weverb

Sorry for the graphs. This should be correct. I turned of my external amp for the first so my mains would not receive anything. Do I have to go into the receiver and tell it there are no main speakers?


----------



## brucek

> I turned of my external amp for the first so my mains would not receive anything. Do I have to go into the receiver and tell it there are no main speakers?


Well, I think you can see that the "sub only" graph is simply not tracking the standard target crossover. 

You simply need to turn off the mains. But, you certainly have to have the mains set at small in your receiver and the crossover set at the normal crossover you use (i.e. 80Hz).

BTW, set the measurement level at 75dBSPL. You're a bit high.

brucek


----------



## weverb

brucek

Thanks for your help. The speakers are currently set to small and the crossover is set to 80Hz. When I manual get a reading playing the test tones on the HSU disk, I get a graph that looks like this (with mains on).


----------



## brucek

That graph also doesn't really make sense. How can the signal after 80Hz continue to produce ~75dBSPL all the way up to 250Hz. The crossover is suppose to continue to reduce the signal above the crossover frequency.... The signal should act like the target REW shows. This is a bit confusing.

I would suggest to use REW to check out the receivers crossover. Feed the soundcard line-out to the CD or AUX input of the receiver and then feed the receivers sub out signal to the soundcard line-in and do a Check Levels setup and a measure up to 200Hz and see what the graph looks like. It should track the REW ideal target....

brucek


----------



## weverb

The above graph was with the mains on. That is why it continued to produce 75dB. What gets me is the major dip at 80Hz with REW versus the manual reading of 75dB at 80Hz when playing that specific tone. :huh:

I will try your recommendation of testing the crossover. I can say, when I play those different frequencies manually, you can verify that at 80Hz the mains start to play.


----------



## weverb

Found something interesting. My MBM xo has been "out" during all my first testing and that's what all the previous graphs show. I just switched it to "in" and....


----------



## brucek

> My MBM xo has been "out" during all my first testing and that's what all the previous graphs show. I just switched it to "in" and


hehe, now we're getting somewhere.........

So, you have a small peak at 50Hz to deal with and you now know that you need a bit of work at the crossover where the mid bass module starts....... 

Can you reposition your main sub to ameliorate the 50Hz peak?

brucek


----------



## weverb

brucek said:


> hehe, now we're getting somewhere.........
> 
> So, you have a small peak at 50Hz to deal with and you now know that you need a bit of work at the crossover where the mid bass module starts.......
> 
> Can you reposition your main sub to ameliorate the 50Hz peak?
> 
> brucek


Unfortunately due to WAF, I cannot move my main sub for now. Can you elaborate a little more on your thoughts about the crossover for the mid bass? Do you think it should be raised to 100Hz?

Next week, I am going to try and switch the main sub and MBM around and see what readings I get.


----------



## brucek

> Do you think it should be raised to 100Hz?


Nope, you just need to adjust the phase control on one or both of the main sub and mid bass sub, while being careful that an adjustment of phase to the mid bass sub (assuming it has one) does not deteriorate the crossover smoothness between the mid sub and Main speakers. At that point you can also change the receiver sub distance setting so that the main sub and mid sub phase will move in concert against the main speakers.



> I am going to try and switch the main sub and MBM around and see what readings I get


I thought the theory was that the mid unit was to be placed near the listening position.

brucek


----------



## weverb

Ok, they are both set to 180.

In theory yes, the MBM is suppose to be nearfield, but can be moved next to the mains. It is usually done in pairs though.

Looking at the new graph, it looks more like the manual one I plotted. I still don't understand why the 16Hz and 80Hz readings are so different.


----------



## brucek

REW is far more accurate representation of the response than continuous test tones are...

brucek


----------



## weverb

brucek said:


> Nope, you just need to adjust the phase control on one or both of the main sub and mid bass sub, while being careful that an adjustment of phase to the mid bass sub (assuming it has one) does not deteriorate the crossover smoothness between the mid sub and Main speakers. At that point you can also change the receiver sub distance setting so that the main sub and mid sub phase will move in concert against the main speakers.


What am I looking for that shows a smooth crossover between the mid and mains? Am I correct in understanding that my current graph does not show a smooth crossover?


----------



## brucek

> What am I looking for that shows a smooth crossover between the mid and mains?


Well, the mid bass module certainly adds another complication to the mix (whether necessary or not, is another question), but it is no different than a single sub and mains with respect to getting a smooth transition at the crossover.

If you look at the pic below, it shows a typical sub and mains with an 80Hz crossover and the resultant mix is a perfect smooth transition as shown. The mains and sub are both 6dB down at the crossover and they add to a flat line.

That's all there is to it, in a perfect world.

Some people like a bit more bass and add a house curve, but the theory is the same.









An MBM is no different, except now you have three signals to integrate. 

The pic below shows the main sub and then in red, the MBM sub. Add in the mains and you get the idea.

You want them to all add to a straight line..... good luck.... :blink:









brucek


----------



## weverb

brucek :hail: for your help!

Here are a couple graphs. The phase is (MBM setting, main sub setting). Let me know your thoughs.

Graph 1 - MBM XO Out (180,180) Phase
Graph 2 - MBM XO In (180,180) Phase
Graph 3 - MBM XO In (0,180) Phase
Graph 4 - MBM XO In (0,0) Phase
Graph 5 - MBM XO In (180,0) Phase


----------



## brucek

You can see that graph 3 and graph 5 are the best (and quite close). 

You still have a dip, but I wouldn't decide on which setting to use (between graph 3 and 5) until I added the mains to see which setting married with the mains the best.

You've still got that pesky peak at 50Hz, that likely won't go away without equalization or movement of the main sub.

brucek


----------



## weverb

Ok... here we go! :nerd:

Graph 1 - MBM XO Out (180,180) Mains On
Graph 2 - MBM XO Out (0,180) Mains On
Graph 3 - MBM XO Out (0,0) Mains On
Graph 4 - MBM XO Out (180,0) Mains On


----------



## weverb

And more.... :nerd:

Graph 1- MBM XO In (180,180) Mains On
Graph 2 - MBM XO In (0,180) Mains On
Graph 3 - MBM XO In (0,0) Mains On
Graph 4 - MBM XO In (180,0) Mains On


----------



## weverb

So brucek which do you think looks the best so far? I am thinking Graph #2 (MBM XO Out (0,180) Mains On) in the first group of 4 graphs. I am going to try to reposition the MBM to see if it effects the 80Hz dip.


----------



## brucek

I'd say graph 1 looks the best. 

It's a lot easier to do comparisons by using the REW Measured Tab..........

brucek


----------



## weverb

Here is a new graph with rotating the MBM 90 degrees (port facing lp) and switching the phase to 0. Mains are on.


----------



## weverb

Comparison of the two different settings.


----------



## weverb

Rotated MBM so port facing a corner away from LP.


----------



## weverb

Well, after more playing around. I switched...

1. Main sub to max extension
2. MBM is rotated 90 degrees w/port facing lp
3. Main sub phase is 0, and MBM 180
4. Turned up main sub from 4.5 to 5
5. Mains are on
6. Receiver pink noise leveled mains at 75dB and subs at 78.5dB

:hush:

:huh:


----------



## HomeTRNut

Hey weverb,

For me, I would want more in that 20-30Hz region. I love movies and do very little music except for BR & HD-DVD concerts. I am trying to set up several presets on the BFD to compensate for concerts vs action movies.


----------



## weverb

Hey Larry,

I was thinking of adjusting the target up to 78dB and then start looking at applying filters. I do not have a BFD at the moment, but was just playing like I had the ability. Below is a graph of what I was thinking of doing. I know I should not be using 12 filters, I am just playing right now. Let me know your thoughts. The other option I was thinking of trying today was adjusting the main sub up some to increase the 20-30Hz range. Anyone's opinion?

:huh:


----------



## HomeTRNut

Hey weverb,

I would try and lift the 20 - 30Hz region with placement and sub settings and not with an EQ boost. You had a graph before that looked really good in this region. I have also gone a bit over the top with the 12 filters and I am heeding the advice here to limit the amount of filters.:T

Larry


----------



## HomeTRNut

Ok, graph #1 on Post #20 looks like a winner to me. You could set a target curve at 78dB and have very few filters required to tame your peaks.


----------



## weverb

The only thing I did not like about that set-up was that it just died after 20Hz. :yawn:

What do you think about turning up the main sub another .5 on the volume knob? I am still within the 5dB hot range overall for the subs. I am only running 78.5dB for subs versus 75dB for highs (using receiver's pink noise).

Oh yea! The other reason I raised the 20-30Hz section with filters was that I could not lower the ~16Hz section with a filter if it gets boosted too much.


----------



## HomeTRNut

I would turn it up and ya, the BFD can't touch 16Hz...

I like the sound of my room when I have the subs running hot. This is how I progressed: 1 sub: set at 82dB, 2 subs: each set at 78dB and they produced 82dB and 4 subs: each set at 75dB and they produce 81dB.

I am going to try some boost on my recent graph and see what happens.


----------



## weverb

What would be better....

1. Creating a filter with a +6 gain to boost the 20-30Hz range and have it flat to 16Hz, or
2. Turn up the sub volume and have another spike at 16Hz?

I thought we wanted as flat a bass line as possible. :gah:


----------



## weverb

Well I tried turning up the main sub another .5. Now I get 75dB for the mains and 79dB for the subs when playing the pink noise from the receiver. I also set the target at 78dB.


----------



## brucek

A lot of the bass you're hearing now will be coming from that 50Hz peak............


----------



## weverb

brucek said:


> A lot of the bass you're hearing now will be coming from that 50Hz peak............


Yup. It is time to tame that beast. How does the rest of the graph look? What are your suggestions for filters?


----------



## brucek

> What are your suggestions for filters?


That's what REW is for............

brucek


----------



## HomeTRNut

weverb said:


> What would be better....
> 
> 1. Creating a filter with a +6 gain to boost the 20-30Hz range and have it flat to 16Hz, or
> 2. Turn up the sub volume and have another spike at 16Hz?
> 
> I thought we wanted as flat a bass line as possible. :gah:


This is fun, right!:bigsmile:

Your constant is the peak at 50Hz. What does it sound like in your room without the 50Hz peak? I think you are ready to find out with the purchase of a BFD or the Anti-Mode.:whistling:

I am chasing the smoothest sound possible in my room and to my ears and the REW shows me graphically what that looks like. I like the Hard Knee House Curve for movies in Max Ext Mode on the subs and I like the standard house curve for concert movies in Max Output on the subs, YMMV.

The last time I looked, zzsounds.com had the BFD for 1 Ben Franklin.:bigsmile:


----------



## weverb

Without any smoothing, it said there was a peak at 49.1 and 71 Hz. It created a filter at 49.1 Hz with a -14 gain and one at 71Hz with -9 gain.


----------



## HomeTRNut

Hi weverb, here is the link to an article here that resonates with me:

http://www.hometheatershack.com/for...target-levels-hard-knee-house-curve-long.html


----------



## weverb

So I guess the two filters would be a good place to start. I guess the two dips it shows really will not be the true response once they are applied. I have been watching for a used 1124P. They seem to be a pretty hot item. They go very quickly.

I demoed War of the Worlds and there is just a tremendous amount of more bass now. I know I will not be needing any buttkickers any time soon. :bigsmile:

I am still trying to wrap my head around the whole house curve idea. How do you go about seeing if you need one? Do you have REW play a 100Hz sine wave and then a 30Hz and see what volume difference you hear?

I have read the link you posted a couple of times. I like what he says about changing the vertical limits. My graph looks a lot more subtle that way.


----------



## HomeTRNut

I use the Hard Knee HC for movies only and switch back to a standard curve for music titles. I just like the way it sounds and feels for movies. I am going to change the gain on the filters to reflect the new vertical limits and see what it sounds like.

Larry


----------



## brucek

> It created a filter at 49.1 Hz with a -14 gain and one at 71Hz with -9 gain.


Did you use Optimize PK Gain & Q?

brucek


----------



## weverb

I just did...

1. Find peaks between 20-80Hz.
2. Assign Filters.
3. Optimize PK Gain & Q

And....


----------



## JohnM

Increase the cutoff frequency for the subwoofer target so that it matches the cutoff of the MBM then redo the optimise for the filters, at the moment the target is not correct for the system.


----------



## HomeTRNut

weverb, you are one BFD away from hearing the dotted line in your room.:jump:

Do you have a Birthday coming up?:bigsmile:


----------



## weverb

JohnM said:


> Increase the cutoff frequency for the subwoofer target so that it matches the cutoff of the MBM then redo the optimise for the filters, at the moment the target is not correct for the system.


Sorry John, I am still very new to this and really appreciate you commenting on my situation. Is this better?


----------



## brucek

Simply set the cutoff in REW to the cutoff of the MBM module, so you can include the peaks that it is responsible for...

brucek


----------



## weverb

brucek said:


> Simply set the cutoff in REW to the cutoff of the MBM module, so you can include the peaks that it is responsible for...
> 
> brucek


Gotcha. That's is what I did. My MBM is xo at 80Hz. I did a search for peaks between 20 - 80Hz.

Although looking at my graphs, I have been debating about playing with the xo point. that transition between the MBM (80Hz) to the highs does not look smooth. Just a reminder, the last few graphs have all been with the mains on.


----------



## JohnM

If your mains are on then the target shape should be full range - basically a flat line plus whatever house curve response you are targeting, if any. The target response that rolls off at the high end is only appropriate when you are measuring with the mains off and the sub crossover filter is active, it then shows what the ideal response would be. Once the mains are added in your ideal is for everything to be flat, so that is the target response you want REW to aim for when applying filters.


----------



## weverb

Well I read the house curve section again. I used REW to play a sine wave at 80Hz and had a spl reading of 74dB. I then had REW play a 32Hz sine wave and had a spl reading of 73dB. If I play a 100Hz wave, the reading only goes to 75dB. Am I understanding correctly that I do not need much of a curve?


----------



## brucek

> play a 32Hz sine wave and had a spl reading of 73dB. If I play a 100Hz wave, the reading only goes to 75dB. Am I understanding correctly that I do not need much of a curve?


You may have missed the point. You *measured* basically the same level at 32Hz and 100Hz - now, how did *you perceive* it?

From the house curve article you read, it says:

_a house curve is perceived flat response as opposed to measured flat response._

It then says:

_After your sub’s response is reasonably smooth, play a couple of sine wave test tones, one at 100 Hz (or whatever your sub’s crossover frequency is), the other at about 32 Hz. (Naturally, you don’t want either of these to be in a null - shift your test tone up or down if you have to.) With measured flat response (or a less-than-optimal house curve), the 100 Hz tone will sound louder than the 32 Hz tone. If that’s what you find, your sub’s response needs to be adjusted so that both test tones sound like they’re the same volume level. Yes, that’s a highly subjective evaluation, but remember a house curve is perceived flat response – that is, it sounds flat, not measures flat._

brucek


----------



## weverb

Ok, maybe this time I got it. I relistened to the two tones and adjusted the volume to see about a 5dB difference. I then created a house curve of 80 0.0 and then 30 5.0. I adjusted my target to 75dB and loaded the house curve.

Once loaded, I applied 1/3 octive smoothing and had REW find the peaks from 20-80Hz and create filters. After optimize PK and adjust PK, I reviewed the filters. REW only created one filter (@ 49Hz). I added a second to boost the 23-31Hz range. So the filters look something like this....

1. PA 49.00 -9 12 for 13.9Hz
2. PA 26.62 +6 17 for 10.7Hz

Am I on the right track now?


----------



## brucek

> Am I on the right track now?


Looks pretty good..........

brucek


----------



## weverb

Thanks for all your help brucek :hail:!

Anything else I could do to improve? I finally have a Behringer DSP1124P on the way. Now to just :daydream: until it gets here.


----------



## Wayne A. Pflughaupt

weverb said:


> Once loaded, I applied 1/3 octive smoothing and had REW find the peaks from 20-80Hz and create filters. After optimize PK and adjust PK, I reviewed the filters. REW only created one filter (@ 49Hz). I added a second to boost the 23-31Hz range. So the filters look something like this....
> 
> 1. PA 49.00 -9 12 for 13.9Hz
> 2. PA 26.62 +6 17 for 10.7Hz
> 
> Am I on the right track now?


Yes, but the idea is for equalized response to track the house curve Target. Another filter centered between 60-70 Hz ought to do it...

Regards,
Wayne


----------



## HomeTRNut

weverb said:


> I finally have a Behringer DSP1124P on the way. Now to just :daydream: until it gets here.



:jump::jump:, Thank you for sticking with it, weverb. I learned so much from this discussion.:bigsmile:

Line up your demo scenes and music tracks.:T

Larry


----------



## weverb

HomeTRNut said:


> :jump::jump:, Thank you for sticking with it, weverb. I learned so much from this discussion.:bigsmile:
> 
> Line up your demo scenes and music tracks.:T
> 
> Larry


I already started today! I am not sure if the slight feeling of nausea is from not eating or too much bass! :bigsmile:


----------



## weverb

Thanks to Wayne's suggestions....

1. PA 26.62 +6 17 for 10.7Hz.
2. PA 49.00 -9 12 for 13.9Hz.
3. PA 66.4 -5 9 for 14.1Hz.

Results in..


----------



## HomeTRNut

^^

Looks good, weverb! Have you been studying/lurking in the BFD forum?


----------



## weverb

No. The deal for the Behringer fell through, so I am lurking for a used one still. I have a couple of feelers/inquires out there though.


----------



## HomeTRNut

I am sure you want to :explode:


----------



## weverb

Was just playing around this morning.

Red - main sub and MBM
Green - main sub only (xo active 40-45Hz)
Gold - MBM only (xo bypassed)

Look like my receiver is still sending a lfe signal even after it's setting of 80Hz and the main sub does not fall off very quickly! :huh:


----------



## weverb

Looks like I can remove the Noob now on the title. Here is my new graph.

Red - BFD off
Green - BFD on

I am only using three filters. :jiggy:


----------



## Wayne A. Pflughaupt

Looks great! Might want to pull your 66 Hz filter down a few more dB , so that everything >45 Hz overall tracks the house curve a bit better. Too much up there compared to below there can make things sound a bit bloated.

Regards,
Wayne


----------



## weverb

Thanks Wayne,

I appreciate your feedback and help. :hail: I figured I would start to listen to material before making any more changes. The hard knee curve will more than likely make its way into my set-up.


----------



## weverb

Well, after a lot of help from Wayne and bruceK, I have decided to move on to my mains. First things first, I only have a RS meter for now. I will decide to get a better mic depending how this process goes. Here are graphs of my sound card and actual measured sound card. It looks like there is going to be problems trying to measure anything over 2kHz with this sound card. Am I looking at this correct, or is all that variation ok?


----------



## brucek

> Am I looking at this correct, or is all that variation ok?


All that variation is less than a dB. 

To test that the soundcard file works and that your card is good, simply connect a cable from line-out to line-in and take a measurement with the newly created soundcard cal file loaded in REW. It will return a flat line............

brucek


----------



## weverb

brucek said:


> All that variation is less than a dB.
> 
> To test that the soundcard file works and that your card is good, simply connect a cable from line-out to line-in and take a measurement with the newly created soundcard cal file loaded in REW. It will return a flat line............
> 
> brucek


That's what I did to get the bottom graph. Can you explain how to test the highs? When I went to try today, the measurements were steadily declining after 200Hz. It looked like the highs were almost not turned on. I tried setting the level to 81dB using the REW sub cal signal to get a 75dB reading from the highs. These are the readings I get when I use the receiver's pink noise test. Then I tried setting the level using the REW speaker cal signal. Not once did the mains maintain the level at which the calibration was set to. Every time, after 200Hz, they just started taking a nose dive all the way out to 20kHz. I did not save the graphs because I thought there was no point since something was incorrect.


----------



## weverb

Does having the loopback always connected effect the testing of the highs?


----------



## brucek

> That's what I did to get the bottom graph.


No, that's a test of the loopback cable without the soundcard cal file loaded.
Are you sure you created the soundcard file on the right channel with the cable on the right channel and then saved that file and did the test measurement on the right channel. The left channel is never used, and you do not check the box that says "Use left channel as calibration reference"..



> Does having the loopback always connected effect the testing of the highs?


Huh???

brucek


----------



## weverb

I was just wondering about the loopback connection. It just mentions it is optional. Did not know if it needs to be connected all the time.

Here is a snap shot of the settings.


----------



## weverb

brucek said:


> No, that's a test of the loopback cable without the soundcard cal file loaded.
> Are you sure you created the soundcard file on the right channel with the cable on the right channel and then saved that file and did the test measurement on the right channel. The left channel is never used, and you do not check the box that says "Use left channel as calibration reference"..


What I don't understand is everything works fine for the sub. The highs just seem to drop off almost 25dB compared to the <200Hz frequencies.


----------



## brucek

> What I don't understand is everything works fine for the sub. The highs just seem to drop off almost 25dB compared to the <200Hz frequencies


Can you tell me what you are trying to measure and what frequency range you're talking about. 

Hopefully your receiver is in stereo only mode and all soundfields are shut off.

Your settings page looks fine (other than I would select the line-in and line-out device in the pulldown rather than the Default you're using). 

brucek


----------



## Wayne A. Pflughaupt

> Can you explain how to test the highs? When I went to try today, the measurements were steadily declining after 200Hz.


Under the "Target Settings" button on the left side of the REW screen, change the "Speaker type" from SUBWOOFER to FULL RANGE. Then go to the "Graph Limits" icon at the top right of the screen and change the Right axis limit from 200 to 20,000. You should be good to go then.

Keep in mind that the Radio Shack meter is only going to be good out to 5 kHz or so...

Regards,
Wayne


----------



## weverb

Here is what I am getting when I try to measure to 20kHz....


----------



## brucek

Turn off your sub and measure one main speaker by itself from 15Hz-20000Hz. Be sure to use the correct Main speaker pink noise to Check/Set levels and use a 75dB target.

Post the graph..........

brucek


----------



## weverb

brucek said:


> ...measure one main speaker by itself from 15Hz-20000Hz. Be sure to use the correct Main speaker pink noise to Check/Set levels and use a 75dB target.


That should help. It is currently going through both main speakers.


----------



## brucek

> That should help.


Well, I don't know about that. I'm just trying to establish what sort of problem you have. It looks like an equalizer setting is turned on somewhere (in the soundcard, in the receiver). Did you go through all the soundcard settings and be sure all soundfields and mixers and EQ and boost etc are shut off?


----------



## weverb

Ok (with 1/3 smoothing applied)....

Green is right
Purple is left


----------



## brucek

And when you use your receiver test tones to set the speaker levels, you have the sub about the same level as the other speakers?

Are the two plots above with the speakers set as large without a crossover engaged?

brucek


----------



## weverb

brucek said:


> And when you use your receiver test tones to set the speaker levels, you have the sub about the same level as the other speakers?
> 
> Are the two plots above with the speakers set as large without a crossover engaged?
> 
> brucek


When I use the receivers pink noise, the mains are at 75dB and the subs combined are at 81dB.

The two graphs are the mains set to small with a xo at 80Hz. I think I posted earlier that it looks like my receiver's xo is not working. When you look at my last graph of the subs, the DSP1124P has taken care of all the spikes at 50Hz. Now there just seems to be two in the 80-150Hz range. I can probably get them under control with the DSP1124P because,looking at the two graphs of the highs, those spikes are being caused by the subs.


----------



## brucek

> The two graphs are the mains set to small with a xo at 80Hz. I think I posted earlier that it looks like my receiver's xo is not working.


Well, it sure looks like you have an enormous peak at 50Hz that the mains are contributing to the mix of sub and mains.

If you look at the pic below, it's a standard crossover at 80Hz (2nd order) with the target at about 70Hz (which would roughly match the level of your graph). It makes me think that you may not have the crossover engaged, but I could be wrong and you simply have a large peak. The one peak at 50Hz is about 85dB, where it should be at the target of about 60dB at 50Hz. That's a 25dB peak.










When you think about the receivers test tone for setting levels, it may include the frequencies of that peak and so your level of the mains is low because of the energy in that 50Hz peak. The only suggestion I might have is to move the mains or raise the crossover perhaps.

brucek


----------



## weverb

Well, I checked my receiver yet again and the crossover is set to 80Hz and the mains are set to small. I popped in a test disc with different frequencies and played the 50Hz tone. Sure enough, the mains were playing. :hissyfit:

So at this point, would it be cheaper to....

1. Try and get a new receiver (try and sell my current one)?
2. Try and get my current one fixed (passed its warranty period)?
3. Buy a eq and use its high/low pass filters like xo's?
4. Buy a good external xo? Any recommendations?

Any other options....?


----------



## Wayne A. Pflughaupt

weverb said:


> Well, I checked my receiver yet again and the crossover is set to 80Hz and the mains are set to small. I popped in a test disc with different frequencies and played the 50Hz tone. Sure enough, the mains were playing. :hissyfit:


Of course they were. That doesn't necessarily mean the crossover isn't working. What you should do is, if you're checking to see if the mains are being filtered, play a test tone at the crossover frequency and take an SPL reading. Make sure it's fairly high, say 80-85 dB. Then take another SPL reading one octave lower - 40 Hz if the crossover frequency is set for 80 as you said. The 40 Hz reading should be reduced approximately 24 dB, assuming that is the slope.

Regards,
Wayne


----------



## brucek

> Any other options....?


Test the crossover with a pseudo anechoic near-field test to remove the rooms influence.

Place one main in the middle of the room as far from boundaries as possible and put the mic about a foot or so away from the speaker and redo your single mains test. The result should look closer to the target I suggested (that you should also put on your graph so you can compare - use 80Hz, bass limited, 12dB/octave)

brucek


----------



## weverb

Wayne A. Pflughaupt said:


> Of course they were. That doesn't necessarily mean the crossover isn't working. What you should do is, if you're checking to see if the mains are being filtered, play a test tone at the crossover frequency and take an SPL reading. Make sure it's fairly high, say 80-85 dB. Then take another SPL reading one octave lower - 40 Hz if the crossover frequency is set for 80 as you said. The 40 Hz reading should be reduced approximately 24 dB, assuming that is the slope.
> 
> Regards,
> Wayne


Wayne,

I will give it a try tomorrow. Do you have any other thoughts as to why the mains are so much lower than the lows when trying to use REW? Also, looking at my current response, how well do you think the YDP2006 would help or be applied?

Thanks.


----------



## weverb

brucek said:


> Test the crossover with a pseudo anechoic near-field test to remove the rooms influence.
> 
> Place one main in the middle of the room as far from boundaries as possible and put the mic about a foot or so away from the speaker and redo your single mains test. The result should look closer to the target I suggested (that you should also put on your graph so you can compare - use 80Hz, bass limited, 12dB/octave)
> 
> brucek


Thanks brucek, I will try this tomorrow.


----------



## brucek

> Do you have any other thoughts as to why the mains are so much lower than the lows when trying to use REW?


Yes, that was what I was attempting to explain a few posts above. 

The Radio Shack meter is being tricked by using the test tones in the receiver when you're setting the speaker level trims. The huge peak you have is what the meter is reading and so the mains get set low. You will have to use REW to set your levels between the mains and sub.......

brucek


----------



## weverb

brucek said:


> Yes, that was what I was attempting to explain a few posts above.
> 
> The Radio Shack meter is being tricked by using the test tones in the receiver when you're setting the speaker level trims. The huge peak you have is what the meter is reading and so the mains get set low. You will have to use REW to set your levels between the mains and sub.......
> 
> brucek


With a 5x200 amp, why do I have to turn it up so high using REW to get the highs to 75dB? To get REW to get the mains to 72dB I had to have the volume level on the sound card almost all the way up. When I listen to music, it does not sound too bass heavy. The highs actually sound louder compared to REW. Looking back to before I used REW, the values I was getting when manually measuring where much higher when playing the higher frequencies. Actually, it seems like when I play the sine wave with REW, it is much louder than the measurement sweep.


----------



## Wayne A. Pflughaupt

weverb said:


> Wayne,
> Also, looking at my current response, how well do you think the YDP2006 would help or be applied?


Keeping in mind that this graph that you posted earlier was taken with the RS meter, and it's not accurate all the way out to 20 kHz, and as such this is just a "for instance:" A parametric EQ could address the area where the big dip is centered at ~3kHz, and the peak at 6 kHz, and that would most likely result in a significant improvement in sound quality. Again, if this was an accurate reading.










Not sure what's up with the levels discrepancy. If the mains and subs are calibrated to what sounds like a good blend to you, then what the graph shows should be what's being put out by the system.

Regards,
Wayne


----------



## weverb

Wayne A. Pflughaupt said:


> Of course they were. That doesn't necessarily mean the crossover isn't working. What you should do is, if you're checking to see if the mains are being filtered, play a test tone at the crossover frequency and take an SPL reading. Make sure it's fairly high, say 80-85 dB. Then take another SPL reading one octave lower - 40 Hz if the crossover frequency is set for 80 as you said. The 40 Hz reading should be reduced approximately 24 dB, assuming that is the slope.
> 
> Regards,
> Wayne


Well, I just played a 80Hz tone at 78dB and then played a 40Hz tone. The 40Hz tone went to about 80dB. The subs were off and only the mains were playing. The mains are only rated for 45Hz to 20kHz. The specs say the low cut-off is 300Hz at 12dB/octave.


----------



## Wayne A. Pflughaupt

My apologies weverb, I should have paid more attention to your graph before making that recommendation. Both your purple and green traces show the level at 40 Hz is at least 15-18 dB higher than at 80 Hz. That's certainly going to have an effect. If that little sine wave test got the two within a couple dB of each other, then it looks like your crossover is indeed working. The problem is, with so much acoustic boost happening in your room, all it's able to do is flatten response below 80 Hz. 

What kind of speakers are these? How large is your room (cubic ft.)? Something like having large speakers with mundo bass output in a small room could cause a problem like this...

Regards,
Wayne


----------



## weverb

The room is about 2,300 cubic feet. It is very open, meaning open to another large room (10'x20') and kitchen. Here is a link to the speakers. The ones I have are ESW's which have a slightly different spec.

http://www.triangle-fr.com/WD100AWP...3-kYnVBRtvRA/gamme_Esprit_EX/SYNC_-1267732500

If I had longer speaker wire, I would try moving them out more. Unfortunately, I am sure the WAF will not let them stay out further from the wall though.


----------



## weverb

Changed xo on receiver to 120Hz and took a measurement (green line). I then moved the speaker 18" from the wall (xo still 120) and took a measurement (blue line).


----------



## weverb

I did notice today when disconnecting REW, an audible hum is being introduced when hooking my sound card and REW to the receiver. I think I need to back to school and take a few some sound/acoustics classes. :sad2:


----------



## Wayne A. Pflughaupt

Wow, if that's what they look like with a high pass, it must be downright scary with no filtering!  I don't see how this could not have a detrimental effect on your overall sound quality. Assuming your sub has a peak at the same place, or even if it doesn't, any EQ you do for it will be blown out by the mains. It looks like you may be a candidate for mains EQ as well as subs.

Regards,
Wayne


----------



## weverb

Wayne A. Pflughaupt said:


> Wow, if that's what they look like with a high pass, it must be downright scary with no filtering!  I don't see how this could not have a detrimental effect on your overall sound quality. Assuming your sub has a peak at the same place, or even if it doesn't, any EQ you do for it will be blown out by the mains. It looks like you may be a candidate for mains EQ as well as subs.
> 
> Regards,
> Wayne


Don't forget to look back the sub graphs. The last ones were always with the mains on and that 50Hz peak has been delt with compared to rest of the lows. One benefit I can think of all this is, there is no localization of the bass. :bigsmile:


----------



## brucek

> Changed xo on receiver to 120Hz and took a measurement (green line). I then moved the speaker 18" from the wall (xo still 120) and took a measurement (blue line).


I can tell you that I would bet money that your bass management crossover is not engaged for the input you're using in the graphs you just posted.

I overlayed a 120Hz target where the signal should be, (it would be nice if you posted your plots with the appropiate target shown), and you can see that there is no crossover there - that's a full range speaker (with a 50Hz room mode).









brucek


----------



## weverb

I tried my REW connection in a different analog source on the back of the receiver. I was able to get both speakers to play at the same time while reaching 75dB.

:huh:


----------



## brucek

The only way you're going to solve the problem of whether that's an actual mammoth room mode or a bad crossover is to take the test outside.......... hehe you'll need a long speaker and microphone cable...............

brucek


----------



## weverb

When I use this room mode calculator, it looks like 47Hz is bad!

http://www.bobgolds.com/Mode/RoomModes.htm

Room dimensions are 24' L x 12' W x 7.9' H


----------



## brucek

Yeah, but there's bad and then there's real bad.

I think you take the prize so far as having the single largest room mode peak I've ever seen (or your receivers crossover is not engaged).

It's obvious to me why your mains were so low in relation to your subwoofer. It's because your SPL meter simply reads the level of that peak when using your receivers test tones, and so the rest of the mains above the peak frequency is down about 20dB from the 75dB setting.

The trouble is, that if you set your mains level to an actual 75dB, then that peak would be way too high and would add with the sub to produce an unusable system.

Sure would be nice to take a test outside that room. Outside would be the best option.

brucek


----------



## weverb

What about doing your suggestion of taking a measurement at 1' from the speaker?

Here is a graph of possible room modes. Review the graph in post #64 and the previous one for the highs. It looks like a lot of the peaks correspond to this graph.


----------



## brucek

I'm not doubting that you have a room mode at 50Hz. That's a given.......

I'm doubting your crossover.

OK, try this.

Do a single mains sweep with a crossover of 80Hz and then do the same sweep with the speaker set as large.

Make sure you set the levels for each test and don't move the mic.

Overlay the two plots on the All Measured tab and use the Trace offset adjustment to exactly line up the two plots around the 2KHz area, so that we're comparing apples to apples.

The two plots should show lots of difference below 80Hz.......

brucek


----------



## weverb

:wits-end: No change. :wits-end:


----------



## brucek

As I suspected.

There are lots of settings on receivers today that you may have missed?

I know that most receivers allow settings for each input. Is there any way you're using an input that the settings are enabled as Large Mains? I've even seen receivers that allow a different crossover for mains and sub.

OK, I wonder if the crossover for the sub is working. This one is easy to check.
Feed the soundcard to the receiver as normal, but now feed the soundcard line-in from your receivers subwoofer line output. This is now checking only the receiver, while the speakers and sub have been removed from the mix.
When you set the Check Levels you'll have to fuss with the receiver volume control a bit to get the REW line-in Input level set up, and then do the standard Calibrate to 75dB.
The result should be a text book 80Hz low pass plot.

brucek


----------



## weverb

brucek said:


> As I suspected.
> 
> There are lots of settings on receivers today that you may have missed?
> 
> I know that most receivers allow settings for each input. Is there any way you're using an input that the settings are enabled as Large Mains? I've even seen receivers that allow a different crossover for mains and sub.


There is only one screen to make those settings (see previous picture). I will try and filter through the different inputs and see if anything changes.

I turned down the sub setting to as low as it would go (-12dB) and took a measurement. You will see that pesky 50Hz mode surpassed the sub settings. The mains look to be still off more than 6dB from the lows.


----------



## weverb

Went through all the different inputs and the settings screen did NOT change from small or xo of 80Hz.


----------



## weverb

brucek said:


> OK, I wonder if the crossover for the sub is working. This one is easy to check.
> Feed the soundcard to the receiver as normal, but now feed the soundcard line-in from your receivers subwoofer line output. This is now checking only the receiver, while the speakers and sub have been removed from the mix.
> When you set the Check Levels you'll have to fuss with the receiver volume control a bit to get the REW line-in Input level set up, and then do the standard Calibrate to 75dB.
> The result should be a text book 80Hz low pass plot.


This will have to wait until tomorrow. Can I use any of the subs out after the y splitter and still get the same result? I don't have enough cable to connect before the y splitter.


----------



## brucek

Splitter? I'm guessing you have more than one sub. In that case just disconnect all subs at the splitter and use it as the connection to the soundcard line-in.

brucek


----------



## weverb

brucek said:


> Splitter? I'm guessing you have more than one sub. In that case just disconnect all subs at the splitter and use it as the connection to the soundcard line-in.
> 
> brucek


Yes, LFM-1 EX and MBM-12. I will try and use one the lines from the splitter.


----------



## weverb

brucek said:


> OK, I wonder if the crossover for the sub is working. This one is easy to check.
> Feed the soundcard to the receiver as normal, but now feed the soundcard line-in from your receivers subwoofer line output. This is now checking only the receiver, while the speakers and sub have been removed from the mix.
> When you set the Check Levels you'll have to fuss with the receiver volume control a bit to get the REW line-in Input level set up, and then do the standard Calibrate to 75dB.
> The result should be a text book 80Hz low pass plot.


Was able to give it a try tonight. What is this?


----------



## brucek

> Was able to give it a try tonight. What is this?


Once you clear your meter calibration file (not required since you aren't using a meter right now), you will see that it is a flat response, indicating that the subwoofer output has no crossover enabled.

You don't need to redo the measure after you remove the meter calibration file. Simply select the IR Windows buttons (top right corner) and then select Apply Windows in the popup. This will apply "no cal file" to your measure. You should then show a flat response (instead of the expected low pass response of a 80Hz crossover).

Looks like the subwoofer output is working without a crossover.

The output should look like the target you have showing if you clear the house curve.

brucek


----------



## weverb

brucek said:


> Looks like the subwoofer output is working without a crossover.


So basically, I need a new receiver or some form of filter for the L/R main speakers. :foottap: Any other options? Their cost?


----------



## brucek

> So basically, I need a new receiver or some form of filter for the L/R main speakers.


Well, you would also need a low pass for the sub and high passes for all other five main and surrround channels, so that's not really an option.

And I think you want to be sure that there's a problem. It certainly would appear so from your testing, but you want to be sure. Receivers aren't cheap.

So, let's be sure of the subwoofer measurement you just did, as it's easy and definitive (because no pesky speakers or rooms are involved).

You connected the right channel of the soundcards line-out to your CD or AUX (right and left) input of the receiver.
You connected the subwoofer output of the receiver back to the right channel of the soundcards line-in.
Your receiver is in stereo mode with no soundfield or effects turned on, and you have the CD or AUX input set to (main speakers as small) with an 80Hz crossover and subwoofer enabled.

You ran REW and set up the levels and did a measure from 0-200Hz and the result was a flat line response instead of a low pass filter target.

Is that correct?

brucek


----------



## weverb

brucek said:


> You connected the right channel of the soundcards line-out to your CD or AUX (right and left) input of the receiver.
> You connected the subwoofer output of the receiver back to the right channel of the soundcards line-in.
> Your receiver is in stereo mode with no soundfield or effects turned on, and you have the CD or AUX input set to (main speakers as small) with an 80Hz crossover and subwoofer enabled.
> 
> You ran REW and set up the levels and did a measure from 0-200Hz and the result was a flat line response instead of a low pass filter target.
> 
> Is that correct?


The only variation was that I connected to the splitter on the back of the BFD (which was in by-pass mode).

So.... Yes.


----------



## weverb

Just checked and my center and (2) surrounds only do 100Hz to 20kHz. Where as my mains do 40Hz to 20kHz with a rolloff at 250Hz @ 12dB/octave.


----------



## brucek

Well, I think you can see that the subwoofer loop should have measured with the crossover enabled at 80Hz rather than a straight line.

As an example, here's my processor doing the same test, except I use a 60Hz crossover.

You can see it tracks the target line so close, that it's hidden, except around 10Hz you see it start to drop off a bit. That's what it's suppose to look like. Yours isn't dropping rapidly at 80Hz as it should. It isn't filtered at all. I wish there was some switch you had in the wrong mode.....









brucek


----------



## weverb

brucek said:


> I wish there was some switch you had in the wrong mode.....


Me too. Post #101 shows you that both are on. :huh:


----------



## weverb

> The Radio Shack meter is being tricked by using the test tones in the receiver when you're setting the speaker level trims. The huge peak you have is what the meter is reading and so the mains get set low. You will have to use REW to set your levels between the mains and sub.......


I was thinking about this some more. I understand how it could influence the L/R mains because they can play down to 40Hz. If this is true about the receiver's pink noise and RS meter, why does it sound the same when being played by the center and surrounds. Both speakers can only go to 100Hz. They are both set only 1-2dB higher than the mains. Wouldn't they need to be "boosted" by more than a couple dB?

It is late and I am :snoring:. Maybe I am thinking about it too much.


----------



## JohnM

Don't the LFM-1 and the MBM have their own crossover settings? Try making measurements with both turned off and with one or the other switched on to see which is making the biggest contribution to that peak and try adjusting the crossover settings on the subs.


----------



## weverb

JohnM said:


> Don't the LFM-1 and the MBM have their own crossover settings? Try making measurements with both turned off and with one or the other switched on to see which is making the biggest contribution to that peak and try adjusting the crossover settings on the subs.


Both graphs in post #101 and #107, the subs were turned off. The LFM xo is set to about 50Hz and the MBM is bypassed right now. I can switch the MBM to 80Hz but from the previous graphs, the 50Hz spike was done by the mains (L/R) only.


----------



## brucek

> Don't the LFM-1 and the MBM have their own crossover settings?


It's my understanding that an MBM's crossover is a high pass that controls its mix with the main subwoofers internal low pass (for example, at 50Hz). Then the receiver/processors crossover is set to 80Hz for example to feed the mixed pair. 

This means that the MBM would not have its upper limit controlled if a receiver/crossover was not engaged...

brucek


----------



## weverb

brucek said:


> It's my understanding that an MBM's crossover is a high pass that controls its mix with the main subwoofers internal low pass (for example, at 50Hz). Then the receiver/processors crossover is set to 80Hz for example to feed the mixed pair.
> 
> This means that the MBM would not have its upper limit controlled if a receiver/crossover was not engaged...
> 
> brucek


The MBM design naturally rolls off at 45-50Hz, therefore no xo needed (just one on the main sub to blend). It is capable up past 120Hz. The typical set-up is to use the receiver's xo (usually set to 80Hz for nearfield placement) to blend with the mains and not be localized. There are set-ups where two are placed up front with the mains and are xo at 120Hz. Still though, the receiver's xo is used.


----------



## JohnM

Try inverting the phase on the LFM, leaving the crossover about 50Hz, so that it counters the mains.


----------



## weverb

Ok, this is strange. I went into the receiver and played with turning the sub off and on. Then messed with xo setting. I pushed it up to 200Hz. I ran REW again and made a graph just like in post #101. I then played the HSU disc with the different frequency tones and got this:

50Hz - 64dB
63Hz - 57dB
80Hz - 57dB
100Hz - 60dB
125Hz - 67dB
160Hz - 72dB
200Hz - 71dB

:huh:

Is it possible because the disc is through optical versus REW is through an analog connection there is a difference?


----------



## weverb

I think I am on to something here. Just ran REW through a digital connection and......


----------



## weverb

Looks like the xo works in digital! Here it is at 80Hz.


----------



## brucek

> Is it possible because the disc is through optical versus REW is through an analog connection there is a difference?


Doesn't seem likely, but easy to check. Connect the output of the soundcards digital output to the digital input of the receiver instead of the analog line-out. 

Run the subwoofer test through the receiver like you did and see if there is a crossover..

brucek


----------



## brucek

hehe, you're ahead of my suggestion...........

Yeah, maybe the firmware in the receiver is a bit glitchy on the analog input?
Retry the analog input again...

That looks better..

brucek


----------



## weverb

brucek said:


> hehe, you're ahead of my suggestion...........
> 
> Yeah, maybe the firmware in the receiver is a bit glitchy?
> 
> That looks better..
> 
> brucek


:yay: Thank goodness all my connections are through digital and not analog. I guess I better double check the subs!


----------



## Jason_Nolan

weverb said:


> I am trying to start using REW. Can you please help point me in the right direction on measurments. This is the graph I am getting. What am I missing? :huh:


I'm having the exact same problem, yet even with the advice Brucek gave you, I cannot figure it out?! Hmm...Any helpers, please.

Yeah, I've never used anything like this before. So I'm a bit ignorant.:huh:


----------



## Wayne A. Pflughaupt

Jason_Nolan said:


> I'm having the exact same problem, yet even with the advice Brucek gave you, I cannot figure it out?! Hmm...Any helpers, please.


Welcome to the Forum, Jason! We're happy to help, but it would be best if you started a new thread. That way we can concentrate on your specific issues. :T

Regards,
Wayne


----------



## weverb

Well I just set-up Wayne's hard knee curve. Now I need to go listen. My next step is focusing on the highs. I have a Yamaha YDP2006 on the way for my L/R mains.


----------



## HomeTRNut

^^^

I :hail::hail::hail: to you weverb. Awesome graph! How does it sound?

Larry


----------



## weverb

So far it sounds real good with music. I have not had a chance to watch any movies yet. I am curious to see what the ECM8000 mic says it looks like. I never thought I would say that I could not wait for Monday! :newspaper:


----------



## weverb

New toys arrived. :nerd:

I don't think the WAF will accept pic #1!


----------



## weverb

Wow! The ECM8000 is getting a total different response for the highs. The 1st graph compares the ECM to the RS meter. The second is the result by itself. :nerd:


----------



## weverb

Measurement of center only. :nerd:


----------



## Wayne A. Pflughaupt

Did you create a calibration file for the mixer (same process as creating one for the sound card)? And I assume you’re using our ECM calibration file?

The reason I ask, your response above 10 kHz looks pretty um, wild...

Regards,
Wayne


----------



## weverb

Wayne A. Pflughaupt said:


> Did you create a calibration file for the mixer (same process as creating one for the sound card)? And I assume you’re using our ECM calibration file?
> 
> The reason I ask, your response above 10 kHz looks pretty um, wild...
> 
> Regards,
> Wayne


No I did not. Did not know it would change. 

Yes, I downloaded the ECM cal file and loaded it. I also turned c weighting off.


----------



## weverb

Wayne A. Pflughaupt said:


> Did you create a calibration file for the mixer (same process as creating one for the sound card)?


Thinking about it a little more, how do you do this? Do I remove the ECM8000 and run the signal through there with a cable?


----------



## Wayne A. Pflughaupt

Also make sure all the mixer tone controls are set to flat...

It looks nifty-keeno in that cabinet. Tell the wife you need a second one to fill that hole. :laugh:

Regards,
Wayne


----------



## Wayne A. Pflughaupt

weverb said:


> Thinking about it a little more, how do you do this? Do I remove the ECM8000 and run the signal through there with a cable?


Yup. And an output back to the soundcard. At least I think that's how it's done, I've never done it myself. brucek will hopefully correct me if I'm wrong about that.

Regards,
Wayne


----------



## weverb

Wayne A. Pflughaupt said:


> Yup. And an output back to the soundcard. At least I think that's how it's done, I've never done it myself. brucek will hopefully correct me if I'm wrong about that.
> 
> Regards,
> Wayne


So it is line out from the sound card to an input where the mic should be. Then out of the 802 to the input of the sound card. Do I continue to keep the optional loop back connection on the sound card also? Does the phantom power need to be on or off during this?


----------



## weverb

Wayne A. Pflughaupt said:


> Also make sure all the mixer tone controls are set to flat...
> 
> It looks nifty-keeno in that cabinet. Tell the wife you need a second one to fill that hole. :laugh:
> 
> Regards,
> Wayne


I set all the dials per the picture reference in the connections basics post:

http://www.hometheatershack.com/for...ards/10001-rew-cabling-connection-basics.html


----------



## brucek

> Do I remove the ECM8000 and run the signal through there with a cable?


No, you use the line-in.......



> Do I continue to keep the optional loop back connection on the sound card also?


Continue? You shouldn't have it there at any time. You're using the soundcard cal file method - not the "Use Left Channel as Calibration Reference" method.



> Does the phantom power need to be on or off during this?


Doesn't matter, you're not using the mic input. This is all line level.

brucek


----------



## weverb

Ok does this look right?


----------



## brucek

Yep........


----------



## weverb

Ok then here we go..........

New corrected highs and lows. I adjusted my xo to 100Hz.


----------



## weverb

New corrected center......:nerd:


----------



## weverb

Played around with a couple of filters for the highs. Just trying things out so far. :dumbcrazy:


----------



## Wayne A. Pflughaupt

Looks pretty good. Looks like you have a good command of what needs to be done, in that your filters are only affecting the problem areas and nothing above or below. :T

Looks like you have a pretty stiff boost in that 2500 area, though. I’d like to see you keep any adjustments, especially boosts, under 6 dB if possible. Also, I’m not sure the 325 Hz problem is wide enough to worry about.

Go ahead and save those filters to memory, just to have them for the sake of comparison, and try this in a new memory: 

Move the Target Curve to 73 dB. (1) Adjust the 2500 filter as before (only hopefully with less gain now). (2) See if another filter can reduce the 1200 Hz peak. (3) To tame the top end, try a filter that’s something like 1.5 to 2-octaves wide at 20 kHz (use the Q to octaves conversion table I sent you). Adjust the gain to get response roughly down to the 73 dB line, and the bandwidth so that it doesn’t suck down anything below 7 kHz. (4) See if you can eliminate that obnoxious 50 Hz peak, either with a PEQ filter or the high pass filter. Forget the 6 dB rule for that one, it’s low enough that you could safely use a significant cut.

After you dial in your settings, bypass all filters and play some pink noise. Then switch each filter in and out, one at a time (i.e., check each filter with all others switched off). The goal here is to get an audible improvement in sound quality. So any filter that’s doing us any good, you should hear a noticeable change on timbre (I’m not sure about the viablity of the #2 filter, for instance). If you perceive that a filter is doing nothing audible, or barely anything audible, you might want to consider eliminating it.

With that in mind, check your original ~325 Hz filter to see if it’s giving any audible change in timbre.

When you’re done, play a familiar source and listen with and without EQ, to make the final determination whether or not you’ve achieved an improvement.

Regards,
Wayne


----------



## weverb

Thanks Wayne.

The filter at 2.6kHz is only boosted 6 db. I figured you would not like anything more than that. Plus, from the response, it looks to be right on.

You have given me a lot of info to soak in. I will be back at it tomorrow. More than likely with more questions and graphs.

Thanks again.

:hail::hail::hail:


----------



## weverb

How's something like this:

1. PK 2.6kHz +6.0 Gain Q 3.0
2. PK 17.5kHz -6.0 Gain Q .5
3. PK 1.2kHz -4.0 Gain Q 3.5
4. HP 80Hz

:nerd:


----------



## Wayne A. Pflughaupt

Well, looks like you don't need me any more. 

So a single broad filter above 7 kHz wasn't working?

You could probably push the HP up to ~120-150 Hz to pull that 50 Hz thing down even more...

Regards,
Wayne


----------



## weverb

Wayne A. Pflughaupt said:


> So a single broad filter above 7 kHz wasn't working?


Can you explain a little more? I thought I had only used one for about 7kHz. :huh:


----------



## Wayne A. Pflughaupt

Sorry 'bout that, I mistook the 1.2 kHz for 12 kHz... :duh:

Regards,
Wayne


----------



## JohnM

You should be wary of applying filters at the top end of the frequency range if you have not had your mic calibrated, the cal file we have for download may not be (likely will not be) an accurate match for your particular mic at the top end.


----------



## weverb

Here is an update on my highs. I have applied four filters and one high pass filter.

1. 325Hz +6.0 Gain 5.0Q
2. 1.2kHz -3.0 Gain 5.0Q
3. 2.6kHz +6.0 Gain 3.0Q
4. 17.5kHz -6.0 Gain .8Q
5. HP 80Hz

First graph compares highs without filters (purple) to filtered highs (blue/green). The second is the new highs with a target of 73Hz. Playing a pink noise with REW from 200Hz to 20,000Hz, I turned on each filter separately to listen for a difference. The only one I question is filter #2. The third graph shows the response with turning the second filter off. It looks like I have a major problem with 330Hz. I don't think I will be able to fix it with any eq'ing.


----------



## weverb

Swapped out filter #2 for a boost at 850Hz. I was able to hear a difference when playing pink noise again.

2. 850Hz +4.0 Gain 5.0Q

:nerd:


----------



## weverb

Well, I proceeded to move onto making a full range plot. First thing I noticed was that my subs were running way too hot. I decided to check their settings two different ways. The first check was using the receiver's pink noise to verify that all 5 highs were reaching about 75dB. Then the subs were measured and showed to be only running 4-5dB hot compared to the mains. The second check was performed using REW. I used the REW speaker cal signal to verify the mains were at 75dB. I then used the REW subwoofer cal signal. That's when I saw the subs running +12dB hot! :yikes: I redid the REW subwoofer cal signal using just the MBM and verified it was 74-75dB. I then did the REW sub signal on just the main sub with the MBM off and the sub xo bypassed. It was running about 85dB.! :no: I readjusted the main sub down to below 80dB.

Now basically starting over, I redid my REW plots for just the subs (see graph #1) and verified my previous filters and made any adjustments. With the new filters plugged into the BFD, I was able to get the subs back under control (see graph #2).

I thought I was ready to plot a full range graph again. So I turned everything on and calibrated using REW's speaker cal signal to about 73dB. I verified my levels and plotted a full range graph from 15-20kHz (see graph #3). Now another major dip appeared at the 200Hz mark. Being frustrated at this point, I plugged another filter in the mains eq at 195Hz with a +6.0 gain and 8.5Q. Well the result looks a little better (see graph #4), but the subs still look like they are maybe too hot still. I decided to stop and actually take a listen. I played a couple of different cd's (Eagles, jazz, Floyd) and watched the pod scene from War of the Worlds. The bass is way lower. It sounds good, but just not as much "kick". :hsd: Maybe I just need to give it time to sink in as this is how it should sound.

My overall feel for today.....:dizzy::surrender::wits-end:


----------



## HomeTRNut

weverb said:


> The bass is way lower. It sounds good, but just not as much "kick". :hsd: Maybe I just need to give it time to sink in as this is how it should sound.


weverb, I fight this all the time. After about 2-3 weeks, I want to try and tweak it again.:bigsmile:




> My overall feel for today.....:dizzy::surrender::wits-end:


Never Surrender!


----------



## weverb

HomeTRNut said:


> Never Surrender!


Thanks for the encouragement Larry. You are the reason I am in this situation you know! :gah:

I am just....:rofl: with yea.


----------



## HomeTRNut

Yes, I do feel responsible for your pain....:hide:


----------



## weverb

Just for that.... I am going to tell your wife you need an external amp, eq, 802 mixer, ECM8000 mic, and a whole bunch of cables! :demon:


----------



## HomeTRNut

Please do....


----------



## weverb

:rofl: :spend: :rofl2:


----------



## Wayne A. Pflughaupt

JohnM said:


> You should be wary of applying filters at the top end of the frequency range if you have not had your mic calibrated, the cal file we have for download may not be (likely will not be) an accurate match for your particular mic at the top end.


Thanks for clarifying that, John. I was having a hard time swallowing such a severe rise up that high!

Regards,
Wayne


----------



## Wayne A. Pflughaupt

> I verified my levels and plotted a full range graph from 15-20kHz (see graph #3). Now another major dip appeared at the 200Hz mark. Being frustrated at this point, I plugged another filter in the mains eq at 195Hz with a +6.0 gain and 8.5Q.


That’s a pretty narrow filter. Make sure it’s giving an audible improvement (both with the pink noise test and with program material) before you commit to it. Often ultra-narrow depressions aren’t terribly audible.



> Well the result looks a little better (see graph #4), but the subs still look like they are maybe too hot still.


I’d agree. 



> It sounds good, but just not as much "kick". Maybe I just need to give it time to sink in as this is how it should sound.


Have you tried the regular (non-hard-knee) house curve yet? You might like it better. Also, I presume you’ve followed the directions in the house curve article on how to determine the amount of slope you need?

Regards,
Wayne


----------



## weverb

Wayne A. Pflughaupt said:


> That’s a pretty narrow filter. Make sure it’s giving an audible improvement (both with the pink noise test and with program material) before you commit to it. Often ultra-narrow depressions aren’t terribly audible.
> 
> Have you tried the regular (non-hard-knee) house curve yet? You might like it better. Also, I presume you’ve followed the directions in the house curve article on how to determine the amount of slope you need?


Now that I have had time to cool off a bit. I went back and did the pink noise test for my 195Hz filter and could not hear a difference. So I will be removing that one. Any other/more suggestions for the 330Hz dip?

I also went back and set-up a regular house curve on a different memory setting. This way I can try both. In addition, I revisited the house curve technique. I played a 150Hz sine wave (pretty loud) and then played a 30Hz sine wave. I did see a 11-12dB difference on the RS meter to get them to sound at the same level. I also played a 80Hz sine wave compared to a 40Hz sine wave. Once again there was about a 6dB difference to get them to sound the same in volume.

What does that all mean.....looks like my lows might not be off that much. I think I have reached a point now where I just need to sit and listen to a bunch of different material and start judging with my ears.


----------



## HomeTRNut

weverb said:


> I think I have reached a point now where I just need to sit and listen to a bunch of different material and start judging with my ears.



Hello weverb, I have reach this point several times in the last five months and I agree with your advice.:bigsmile:


----------



## weverb

What's the story/difference of this ECM8000 cal file (the first one) versus the one on the download page (the second one)? I found it in one of brucek's postings. There looks to be a very big difference in the upper Hz. :huh:


----------



## brucek

Use the newecm file on the download site. It is the one professionally calibrated and certified by West Caldwell Calibration Laboratories. The other is an old one we used before the professional calibration was carried out.

brucek


----------



## weverb

Thanks brucek. I am just wondering what could be causing my top end of the graphs to go up so much. Nothing sounds overly bright to me.


----------



## weverb

Well , I have started to work on my center channel now. I am using a YDP2006 to eq it and the mains. Here are some graphs for your review....:nerd:

1. Center with no filters.
2. Center with filters.
3. Center compared to mains.


----------



## Wayne A. Pflughaupt

You've certainly got the right idea. :T 

The graphs for both mains and center show an overall sag in response between about 2 kHz and 10 kHz. It would probably make a noticible improvement in SQ to shore that area up a bit with a broad filter.

Looking at your center baseline graph, it looks like the Target Curve should have been lowered to maybe 72-73 dB before you started equalizing. That way less severe filters could be used.

Regards,
Wayne


----------



## weverb

Wayne A. Pflughaupt said:


> You've certainly got the right idea. :T
> 
> The graphs for both mains and center show an overall sag in response between about 2 kHz and 10 kHz. It would probably make a noticible improvement in SQ to shore that area up a bit with a broad filter.
> 
> Looking at your center baseline graph, it looks like the Target Curve should have been lowered to maybe 72-73 dB before you started equalizing. That way less severe filters could be used.
> 
> Regards,
> Wayne


Thanks Wayne, none of the filters were more than +/-6.0dB. I try and take your guidelines to heart when eq'ing. There are only four filters being applied to the center. The first being a high pass filter (obviously), the second is a shelving filter to help with that 200-500Hz. area. The last two are a boost at about 3.0kHz. and a small cut of the very high end to get it to match the mains. I must say, so far the center has been easier than the subs. :bigsmile:


----------



## weverb

Messing around with the rear channel.

1. Rear channel with no filters.
2. Rear channel with filters.
3. Rear channel compared to center.

:nerd:


----------



## weverb

One last confusing graph. Comparing mains, center, and rear channel.

:dumbcrazy:


----------



## Wayne A. Pflughaupt

REW has a function that will off-set the traces for easier comparison...

That rear w/ filters is the best-looking one you've done yet. :T

Regards,
Wayne


----------



## weverb

Wayne A. Pflughaupt said:


> REW has a function that will off-set the traces for easier comparison...
> 
> That rear w/ filters is the best-looking one you've done yet. :T
> 
> Regards,
> Wayne


Thanks Wayne! :hail::hail::hail:

I feel like a young (pardon the silly comparison) Jedi that has just passed basic training. :bigsmile:

I wanted to overlay them to help confirm that all three are following the same trends. I guess I don't really need to worry about the varying dips and peaks. They seem pretty narrow and probably would not hear any SQ improvement by addressing them. Correct?


----------



## Wayne A. Pflughaupt

Probably correct.

Regards,
Wayne


----------



## weverb

Wayne A. Pflughaupt said:


> The graphs for both mains and center show an overall sag in response between about 2 kHz and 10 kHz. It would probably make a noticible improvement in SQ to shore that area up a bit with a broad filter.


Went back and remeasured these and made a few minor tweaks. I was able to still hear a slight "boomyness" to male voices while watching Iron Man. I mostly noticed it with Downey's voice once in a while. Any suggestions? Or is it just from having the center located in a cabinet?

Blue - center channel
Purple - main left and right


----------



## thewire

Could it also be a lobbing effect? This is usually a pretty common problem with alot of center channels. If it is a resonance to do with speech, it should be fairly easy to detect with some simple pink noise. Whether or not is the cabinet or the speaker box itself would be more difficult, and would require removing it from the cabinet to measure I would think.


----------



## Wayne A. Pflughaupt

It could be just that movie, so I wouldn't worry about it unless you hear it with most program material. It's not unusual to find programs with poorly equalized male voices. If you come across one, just adjust the Yamaha to take care of it; I believe it will return to the stored memory setting the next time you power up.

Regards,
Wayne


----------



## weverb

Well, just wanted to put a conclusion to my chapter of REW. This is my final adjustments to my current subs. At least until I get permission for a fourth! :bigsmile: :hide:

I tried my main sub in its "max output" mode and was able to get the first graph as a response. I really felt like I was missing out on something! :sad2:

After working with tech rep for my main sub, I went back to its "max extension" mode and relocated it to the front corner. I was able to get enormous amount of room gain in this location (see second graph). The main problem with this scenario was that my current eq could only go as low as 20Hz.

With Wayne's help and some research, I was able to find an inexpensive eq that would go down to 10Hz. My two main options were a Rane PE17 or a Symterix 551E. I was able to find a brand new Symetrix 551E for $125 shipped. It would be nice to be able to keep my response down to 14Hz., but I will take the +/-2dB smooth response down to 15Hz. If you were to drop my target line 2dB, it does intersect at 14.5dB. :bigsmile: I am happy overall since the main sub is only rate down to 16Hz.

Time to go listen!


----------



## Wayne A. Pflughaupt

An EQ solely dedicated to the octave between 10-20 Hz - now there's a man who takes his subwoofer equalizing seriously! I think you've taken subwoofer equalization to new highs, weverb. Or maybe I should say new lows... 

Regards,
Wayne


----------



## weverb

Wayne A. Pflughaupt said:


> An EQ solely dedicated to the octave between 10-20 Hz - now there's a man who takes his subwoofer equalizing seriously! I think you've taken subwoofer equalization to new highs, weverb. Or maybe I should say new lows...
> 
> Regards,
> Wayne


Thanks Wayne.... I only need four filters total. I could probably use just the Symetrix 551E, but I like the ease of use of the YDP. The YDP is much quicker and easier to make adjustments. I just wish it went lower. :bigsmile:


----------

