# Measuring My Subs and Check Level Questions



## Kix_N_Grins (Feb 14, 2015)

Hello,

I've been playing around with REW taking measurements with a UMIK-1. I'm using two subs in the front of my living room. When I made my first measurements in early April, I had the two subs sitting inside my Mains, between the Mains and TV. Based on my measurements, I was advised to move the subs preferably to the corners of the room (possibly stacking the two subs since I only have one corner). So to start, I've moved the right sub into the right corner of the room, and the left sub is still between the Main and TV.

My first questions have to do Checking the Levels. According to the REW instructions, I should set my AVP to where my SPL measures 75dB. My subs also have internal power amps with their own volume controls. So I set my AVP to -30dB, then used the volume controls on the subs to achieve 75dB on the SPL meter. When I checked the levels on each sub individually, I made sure the SPL were 75dB, but when I measured both subs together, I didn't adjust either volume and it was closer to 84dB. I wanted to make sure that each sub was producing approximately the same SPL. Was this the correct way to do it, when there are more than one sub and they have their own amps/volume controls?

As far as my measurements go, can anybody help me interpret what I'm seeing and what I should do next? Aside from moving the left sub and stacking on the other sub in the corner, I don't really have any options for moving the subs or room treatments. I'm leery of stacking a sub on top of each other, as they weigh 50lbs each and have a flawless piano gloss black finish that I don't want marred over time.

I've attached the SPL charts and mdat file below.

Any advice would be appreciated,

Kix

View attachment Subs.mdat


----------



## Wayne A. Pflughaupt (Apr 13, 2006)

Well sure, you can expect a higher SPL once you fire up both subs together, although 9 dB is more than I’d expect. Still, nothing to be concerned about.

I think you’re fine leaving both subs where they are. I’d equalize based on combined response. :T

Regards, 
Wayne


----------



## Kix_N_Grins (Feb 14, 2015)

Thanks for the reply, Wayne.

When I look at my combined response, my instinct is to do the following:
First, bring 20-24Hz so that it's flat at 90dB, then take the peak between 40-48Hz so that it's flat at 90dB. 
Second, calculate for a hard-knee curve, and focus equalization on 48-80Hz area while also achieving the hard-knee curve I want.

As some back-ground, the output of my AVP is mono for the LFE. I'm "Y"'ing that into the left & right channels of a Yamaha YDP2006, which in turn, go to each sub. So I have 6 independent filters for each sub (and separate delay times to account for different distances). Let me no know if there's a better way to connect it.

Back to equalization... In order to achieve my goals in my first paragraph (if they're correct), I need to adjust the separate left and right subs (charts) to realize what I want in the combined chart.

Am I on track, or totally out in left field? If I am on track, where do I start, 20-24 Hz?

Thanks,
Kix


----------



## Kix_N_Grins (Feb 14, 2015)

You know, after looking at the Combined more... Would it make sense to take everything above 90dB, down to 85 to flatten it out from 18 to 80Hz?


----------



## Wayne A. Pflughaupt (Apr 13, 2006)

Kix_N_Grins said:


> Back to equalization... In order to achieve my goals in my first paragraph (if they're correct), I need to adjust the separate left and right subs (charts) to realize what I want in the combined chart.


Typically it’s a futile effort to EQ the subs independently. What you usually find is that you’ll get a nice graph for each one, but once you fire them both up together, combined response is whacked. It’s best to just EQ them both as a single entity. After all, that’s the way you hear them, right? I'd go ahead and keep the independent delay times, however.




> You know, after looking at the Combined more... Would it make sense to take everything above 90dB, down to 85 to flatten it out from 18 to 80Hz?


 A good approach is to put the target midway between the worst peaks and depressions. I’d suggest 87-88 dB.

Regards, 
Wayne


----------



## Kix_N_Grins (Feb 14, 2015)

Well, here's my first attempt at operating a parametric EQ, and at equalizing my subs as a pair.

Wayne, I tried to follow your articles on House Curves and Hard-Knee House Curves. I wasn't able to EQ the subs with only 3-4 filters, and used all 6 filters. I left the subs connected to the EQ's Left & Right Inputs, then ganged the L&R filters whenever I made an adjustment. It took three tries to finally get it to where it's at. I also set my limits from 20-130dB while doing the adjustments.

Does the chart look okay, or should I work on a straighter descending line from 30 to 90 dB? If it look s okay as-is, what my next steps; the timing on the two subs or start on the mains or something else? Not being able to apply treatment or move the subs, should I care what the water-fall looks like at this time?

I also have a couple questions on the operation of the YDP2006 EQ. First, the little meter on the front of it. It seems to cover 0-20Khz. Is there any way I can re-scale it so that it only covers 0-100Hz? I also noticed that the Freq. adjustments where much coarser as the filter number increased. So when I got to using filters 5 and 6, they didn't have the resolution I would have liked. Is that something that can be adjusted? I would have thought it would be something automatic depending on where I set the center frequency.

Thanks,
Kix

View attachment Subs 2015-09-06.mdat










View attachment 100530


----------



## Kix_N_Grins (Feb 14, 2015)

It didn't like me adding the waterfall graph to the previous post while editing, so here it is...


----------



## Wayne A. Pflughaupt (Apr 13, 2006)

Kix_N_Grins said:


> Does the chart look okay, or should I work on a straighter descending line from 30 to 90 dB?


Looks fine; if you think it sounds good then you’re done. :T




> If it look s okay as-is, what my next steps; the timing on the two subs or start on the mains or something else?


Yes, timing the subs to mains would be good. Isn’t your receiver’s auto-set up doing that? If not the YDP2006 has delays, but I guess you already know that.




> Not being able to apply treatment or move the subs, should I care what the water-fall looks like at this time?


Your waterfall looks good, better than most. :T




> I also have a couple questions on the operation of the YDP2006 EQ. First, the little meter on the front of it. It seems to cover 0-20Khz. Is there any way I can re-scale it so that it only covers 0-100Hz?


There is no scaling adjustment for the meter, nor does any equalizer have this function. However, if the EQ is dedicated to the subs (as it appears that yours is), then obviously it’s only going to meter the lows, as that’s the signal being sent to it.




> I also noticed that the Freq. adjustments where much coarser as the filter number increased. So when I got to using filters 5 and 6, they didn't have the resolution I would have liked.


The frequency-center adjustments aren’t really coarser as the filter numbers increase. It’s because (I assume) you’re using the higher-number filters to adjust higher frequencies. If you dialed those filters’ frequency settings down low, you’d see them doing the same thing as the lower-numbered filters. 

The reason the frequency settings appear coarser at higher frequencies is because the number of whole-numbered frequencies doubles with each successive octave. As an extreme comparison, between 20-40 Hz you have 20 whole-numbered frequencies, while between 8-16 kHz you have 8000. That doesn’t really matter for equalizing purposes, because ultimately an octave is an octave.

So, using the example above, you get 25 “stops” between 20-40 Hz, and also 25 “stops” between 8-16 kHz (same for every octave in between). Naturally, with the latter the frequency settings are further apart numerically, but it’s still functionally the same 1/25-octave resolution anywhere in the frequency spectrum. Any digital parametric EQ is going to be like this (the BFD has 1/60-octave resolution, for example). Only an analog parametric can truly be set anywhere in the frequency spectrum.

Hope this helps. :T

Regards, 
Wayne


----------



## Kix_N_Grins (Feb 14, 2015)

Wayne,

Thanks so much for the info. It was very helpful. I was watching a movie last night and noticed the light on my 5th filter was off. I haven't had a chance to re-measure yet, but I'm sure it'll improve the 45-80Hz area of my hard-knee curve. I thought I had it much closer Friday night when I set the filters.

The AV Preamp I'm using doesn't have any auto-EQ or set-up on speaker distance. It just has a menu where I can set the distance of each speaker in feet. That's pretty straight forward for every speakers but my subs. The Preamp only has one LFE channel output, which I'm Y'ing to the left and right of the sub's PEQ's. The sub that sits between my Left Main and Center is about 9 foot away from the LP, and the sub that I moved to the corner is about 11 1/2 foot away. I currently have the sub delay set at 9 feet in my Preamp, which goes to both. So I'm wondering, is that 2 1/2 ft of difference in distance enough to make an audible affect. I do have the separate L&R delays in the PEQ to alter it. I just don't know if it's worth it, and also don't know how to do it (work it in with all the other speaker delays). 

Thanks again for your advice,

Kix


----------



## Wayne A. Pflughaupt (Apr 13, 2006)

You can get problems with response in the crossover region if the subs aren’t aligned with the mains, so you might want to take a look at that. A full range graph with L/R mains and subs, at least out to 3-400 Hz, would show the problems, if there are any.

Keep in mind that setting delays in the YDP2006 is not the same as with your AVP. The figure you enter will be the difference between the main speaker’s distance from the LP and the sub’s.

Regards, 
Wayne


----------



## Kix_N_Grins (Feb 14, 2015)

Had to clean some volume controls on my amps, but think I'm good for some more testing and learning.

Before plodding into mixing mains & subs together, I'm going to back up a step to focus on just my two subs. With the two subs being at different distances from the LP, do I need to worry about delay/timing so those two signals arrive at the LP at same time?

I went and ran some measurements of the two Subs only (together), the Mains only (together, since my understanding is that's ok since I'm looking at less than 400Hz and how they blend with the Subs), and the Subs & Mains together. Does this look like they will blend together both from a frequency response and timing perspective?

























Here's the .mdat file:
View attachment 2015-10-13.mdat


When I move from testing my Subs versus Mains, do I need to check levels for each set of speakers between measurements, and if so, do I use the same Subs noise found under Preferences Check Levels or switch to Mains noise for that part?

This leads me to a topic that is really confusing to me, namely Volume and Gain controls on various equipment... I have the main volume control on my AVP which adjusts all channels at the same time, my AVP also has independant volume controls for each channel (+-10db) which I look at as a 7-channel balance control, my EQ's each have their own Main gain controls, and the power amps each have their own volume/gains controls (including my Subs which have built-in amps and volume controls). Is there a "proper" sequence or process that should be used in setting all of these volume/gain controls, or when is it more appropriate to use one versus another?

What I've been doing so far is the following: Sitting at the LP with a SPL meter, adjust each channel so that I hear 75db using the noise generator in my AVP. While doing that, I'm simultaneously adjusting the gains on the EQ's so that at the AVP's max volume, the EQ's LED signal indicators just barely touch the first red bar (clipping?). I'm also adjusting the volumes on the power amps so at my AVP's max volume (and main gain settings on EQ's), they don't exceed the ratings of my speakers.

What I noticed when taking these last measurements above is, even though each channel measured the same using the AVP's noise generator and my SPL meter at the LP, while using my UMIK-1 via REW and running the Subs seperate from my Mains, my Mains were MUCH lower in SPL. I ended up adjusting the Main gains on the EQ's to get them closer to the SPL I was getting from the Subs. I hope that all makes sense.....

Any help is appreciated,
Kix


----------



## jtalden (Mar 12, 2009)

Kix_N_Grins said:


> Had to clean some volume controls on my amps, but think I'm good for some more testing and learning.
> 
> Before plodding into mixing mains & subs together, I'm going to back up a step to focus on just my two subs. With the two subs being at different distances from the LP, do I need to worry about delay/timing so those two signals arrive at the LP at same time?


Check that out by measuring each SW separately and also together. It is not required to have the timing adjusted between them, but that is the way to get the most output. If your don't time align them and one is more than 180° out of phase with another you can reverse the polarity in it. Having a smooth enough response that can be EQed is more important than having them time aligned. You may also be able to correct a problem using a phase control on one of the SWs so it better matches the others.



> I went and ran some measurements of the two Subs only (together), the Mains only (together, since my understanding is that's ok since I'm looking at less than 400Hz and how they blend with the Subs), and the Subs & Mains together. Does this look like they will blend together both from a frequency response and timing perspective?


The 'together' trace is not helping fill the XO range SPL sag so timing could be better. You could change the SWs distance setting to improve the SPL support in that range. Try increasing or decreasing SWs distance in ~0.5m increments to find a better setting.



> When I move from testing my Subs versus Mains, do I need to check levels for each set of speakers between measurements, and if so, do I use the same Subs noise found under Preferences Check Levels or switch to Mains noise for that part?


No, You can always just adjust the level trims by looking at the overlay of the channel traces and adjust the trim of each channel as needed. Once trims are set there is no need to keep checking it before measurements. There is a level check option on the 'Make a measurement' popup. It's convenient to use that once before the first measurement of a session just to be sure the volume settings are in your intended target range. Once you know the volume level you test at then there is no need for the check level function; just take a measurement and if it not quite right where you want it make volume change and start again.



> This leads me to a topic that is really confusing to me, namely Volume and Gain controls on various equipment... I have the main volume control on my AVP which adjusts all channels at the same time, my AVP also has independant volume controls for each channel (+-10db) which I look at as a 7-channel balance control, my EQ's each have their own Main gain controls, and the power amps each have their own volume/gains controls (including my Subs which have built-in amps and volume controls). Is there a "proper" sequence or process that should be used in setting all of these volume/gain controls, or when is it more appropriate to use one versus another?


It's a somewhat confusing subject. If you want to learn the process see *Here* or search the web for 'gain structure'. If you have no noticeable noise with no signal and your volume control at typical listening level and you can also obtain the loudest volume you want without clipping then there is no serious issue with gain structure; there usually isn't. It can sometimes be a problem particularly with high efficiency horns and/or when mixing consumer level equipment with pro level equipment. 



> What I've been doing so far is the following: Sitting at the LP with a SPL meter, adjust each channel so that I hear 75db using the noise generator in my AVP. While doing that, I'm simultaneously adjusting the gains on the EQ's so that at the AVP's max volume, the EQ's LED signal indicators just barely touch the first red bar (clipping?). I'm also adjusting the volumes on the power amps so at my AVP's max volume (and main gain settings on EQ's), they don't exceed the ratings of my speakers.


Are you just trying to fine tune the gain structure to optimize it, or do you have a problem to solve? I have never gone to the effort of optimizing the gain structure. I did initially need to adjust mine a bit to get into a reasonable working zone though. I don't use a SPL meter for level checks. As mentioned above just confirm session level by looking at the first measurement trace. No other changes are need for additional channel measurements.



> What I noticed when taking these last measurements above is, even though each channel measured the same using the AVP's noise generator and my SPL meter at the LP, while using my UMIK-1 via REW and running the Subs seperate from my Mains, my Mains were MUCH lower in SPL. I ended up adjusting the Main gains on the EQ's to get them closer to the SPL I was getting from the Subs. I hope that all makes sense.....


If you test the SWs through a redirected main channel (as the FL with the FL main disconnected) then the SWs level should be similar to the mains. If you test the SWs through the LFE channel the SWs level will be +10dB compared to the mains.


----------



## Wayne A. Pflughaupt (Apr 13, 2006)

Kix_N_Grins said:


> This leads me to a topic that is really confusing to me, namely Volume and Gain controls on various equipment... I have the main volume control on my AVP which adjusts all channels at the same time, my AVP also has independant volume controls for each channel (+-10db) which I look at as a 7-channel balance control, my EQ's each have their own Main gain controls, and the power amps each have their own volume/gains controls (including my Subs which have built-in amps and volume controls). Is there a "proper" sequence or process that should be used in setting all of these volume/gain controls, or when is it more appropriate to use one versus another?


JT already pointed you to my gain structure article, but the equalizers don’t require any gain-setting. There’s no reason to max out their input levels. Just leave them set at 0 dB. Going above that increases the equalizer’s noise floor.

Your Carver amplifiers aren’t professional but consumer fare. With pro gear there is a lot of different signal levels to deal with, but with consumer audio equipment you have something of a universal standard for signal levels. Thus I expect that your amps should have their gains set to max. However, if you find that this gets you “hair trigger” action from your pre-amp’s main volume control (e.g. it goes from nothing to virtually full blast with only 25% of its travel range) I’d suggest following the gain structure exercises outlined in the article.

Regards, 
Wayne


----------



## Kix_N_Grins (Feb 14, 2015)

Hello Jt and Wayne. Thanks for the replies and help.



jtalden said:


> Check that out by measuring each SW separately and also together. It is not required to have the timing adjusted between them, but that is the way to get the most output. If your don't time align them and one is more than 180° out of phase with another you can reverse the polarity in it. Having a smooth enough response that can be EQed is more important than having them time aligned. You may also be able to correct a problem using a phase control on one of the SWs so it better matches the others.


I'm using the LFE output of my preamp (mono) and feeding it into the left and right channels of my EQ, which in turn feeds my left and right subs. Connecting this way gives me 6 filters per sub, and separate time delays. Per Wayne's advice, I'm using the same filters for both subs, so the only thing I'm gaining by connecting this way is the separate delays. So my thought is that if I don't utilize the delays, I might as well connect the EQ as a single mono channel and have 12 filters for the subs (since the filters are identical anyway). The freq response of my subs to my novice eyes doesn't look too bad, but with 12 filters instead of 6, I could probably make it that dead-knee house curve straight as an arrow (I know, that doesn't sound right). So, that's what I'm debating... 



jtalden said:


> The 'together' trace is not helping fill the XO range SPL sag so timing could be better. You could change the SWs distance setting to improve the SPL support in that range. Try increasing or decreasing SWs distance in ~0.5m increments to find a better setting.


I can set my SW's distance either in my AVP (in 1/2 ft increments), or by using the delays in the EQ. I chose adjust it in the AVP (let me know if the EQ's would be better). Before any adjustment, the subs were set at 9 feet (8.5 feet being my center channel and closest front speaker). I think the most improvement is when I adjusted the subs distance to 12 feet, but I'm really not sure what to look for other than making things flat at 70-100Hz. Does the following chart look like enough improvement? I'm also curious about the distance settings in the AVP. Is the actual delay in mS based off the closest speaker (0 mS) and the differential of the further speakers distance?











jtalden said:


> If you have no noticeable noise with no signal and your volume control at typical listening level and you can also obtain the loudest volume you want without clipping then there is no serious issue with gain structure; there usually isn't. It can sometimes be a problem particularly with high efficiency horns and/or when mixing consumer level equipment with pro level equipment.
> 
> Are you just trying to fine tune the gain structure to optimize it, or do you have a problem to solve?


As Wayne mentioned, most is consumer but the EQs are pro. So it's mixed. At louder volumes, I do hear some buzzing noise. It's much more pronounced if I switch the EQ's to +4dB attenuation versus -20dB, so I keep the back switches set to -20dB. So I guess I'm trying to optimize and get the most out of my equipment, but possibly also have a problem. As I learn how to use the EQ's, I may be able to use the notch filters to get rid of the buzz (without ruining the sound).



Wayne A. Pflughaupt said:


> Your Carver amplifiers aren’t professional but consumer fare. With pro gear there is a lot of different signal levels to deal with, but with consumer audio equipment you have something of a universal standard for signal levels. Thus I expect that your amps should have their gains set to max. However, if you find that this gets you “hair trigger” action from your pre-amp’s main volume control (e.g. it goes from nothing to virtually full blast with only 25% of its travel range) I’d suggest following the gain structure exercises outlined in the article.


I have all of the amps set to max except for the subs (built-in amps) and the amp I'm using for the Mains. I keep the amp down some on the Mains because it's rated at 225W/ch and the speakers are rated at 175W/ch. I have a 25 year old son that visits over the weekend and likes things louder than I do. :bigsmile:

I do have a question on the gain switches on the back of the Yamaha EQ's. There's one switch for the input atteenuation and one for the output. I think I understand why a person would have both set to +4dB or both set to -20dB. When would a person have the input set to -20dB and the output set to +4dB (or vice-versa)? Consumer theatre equipment and pro amps, or pro theatre equipment and consumer amps?

Thanks again for any help,
Kix


----------



## Kix_N_Grins (Feb 14, 2015)

Here's something else that's been perplexing me the past week while trying to integrate the Mains & Subs...

When I use REW, play my turntable, or use a mp3 player, I'm routing the signals through a Beresford TC-7240 Line Level Audio Router. Basically, it's a nice A-B-C-D switch box that feeds into my AVP. I only have a total of 5 inputs on the AVP, and it's my way of having 3-4 line-level signals and only take up one input on the AVP.

My target level of the Mains integrating into the hard knee house curve on the subs is ~78dB. After making the necessary gain adjustments to achieve the chart in my previous post #14, everything sounds great when I listen to my mp3 player or turntable (maybe a little loud on the Mains). However, when I listen to anything from my Samsung Blu-ray (You-tube, Netflix, etc) connected to my AVP via HDMI, the Mains are over-bearing and I can't hear the subs at all from the LP. So, I turn down the Mains using the input gain control on the Mains EQ until it "sounds right" to my ears.

The next time I take measurements using REW, the following chart is what my freq response looks like, until I readjust the gain on the Main EQ back to where it was on my last measurements.

Any thoughts? I've ohm'd out the A-B-C-D switch and it is basically a short (no resistance).

Kix


----------



## jtalden (Mar 12, 2009)

Kix_N_Grins said:


> I'm using the LFE output of my preamp (mono) and feeding it into the left and right channels of my EQ, which in turn feeds my left and right subs. Connecting this way gives me 6 filters per sub, and separate time delays. Per Wayne's advice, I'm using the same filters for both subs, so the only thing I'm gaining by connecting this way is the separate delays. So my thought is that if I don't utilize the delays, I might as well connect the EQ as a single mono channel and have 12 filters for the subs (since the filters are identical anyway). The freq response of my subs to my novice eyes doesn't look too bad, but with 12 filters instead of 6, I could probably make it that dead-knee house curve straight as an arrow (I know, that doesn't sound right). So, that's what I'm debating...


That's fine. Your SW response in Post 11 was very smooth so it doesn't appear you need either delay or more filters to get a good bass response. 



> I can set my SW's distance either in my AVP (in 1/2 ft increments), or by using the delays in the EQ. I chose adjust it in the AVP (let me know if the EQ's would be better).


Either place is fine.



> Before any adjustment, the subs were set at 9 feet (8.5 feet being my center channel and closest front speaker). I think the most improvement is when I adjusted the subs distance to 12 feet, but I'm really not sure what to look for other than making things flat at 70-100Hz. Does the following chart look like enough improvement?


Typically I would adjust the distance to provide the maximum SPL through the XO range (about 30-180Hz in this case). This lets the SWs operate with the lowest power consumption and excursion for a given output. It also usually minimizes the amount of EQ boost that is needed. This practice is not critical however so long as you have enough capacity in the SWs to handle the SPL levels you use. Your chart shows that the initial 9ft red curve SPL is higher than the adjusted 12ft curve with the exception of a slight reversal above 120Hz. My standard recommendation would then be to use the 9ft setting and adjust the EQ accordingly to achieve your house curve. 



> I'm also curious about the distance settings in the AVP. Is the actual delay in mS based off the closest speaker (0 mS) and the differential of the further speakers distance?


In the AVP the furthest speaker is set to 0ms delay and the closer speakers are delayed appropriately. 



> As Wayne mentioned, most is consumer but the EQs are pro. So it's mixed. At louder volumes, I do hear some buzzing noise. It's much more pronounced if I switch the EQ's to +4dB attenuation versus -20dB, so I keep the back switches set to -20dB. So I guess I'm trying to optimize and get the most out of my equipment, but possibly also have a problem. As I learn how to use the EQ's, I may be able to use the notch filters to get rid of the buzz (without ruining the sound).


The noise is possibly a ground loop issue. I will let Wayne or someone with more experience help you with that type of problem. It shouldn't do that and it is best to identify the source of the problem and correct it. 

The -20dB settings are the correct ones for your equipment.


----------



## Wayne A. Pflughaupt (Apr 13, 2006)

I must say I’m impressed with your equipment list, Kix. You’re probably the only other person I know of who has more of those Yamaha EQs than I do. Must be an impressive looking rack!




Kix_N_Grins said:


> So my thought is that if I don't utilize the delays, I might as well connect the EQ as a single mono channel and have 12 filters for the subs (since the filters are identical anyway). The freq response of my subs to my novice eyes doesn't look too bad, but with 12 filters instead of 6, I could probably make it that dead-knee house curve straight as an arrow (I know, that doesn't sound right). So, that's what I'm debating...


Probably not a good idea to go overboard with the equalizing. Filters with small gain values aren’t really audible anyway. One benefit of going with the 12-filter mono setting would be that you could lose the “y” cable, as whichever input you use will give the signal to both outputs.




Kix_N_Grins said:


> I do have a question on the gain switches on the back of the Yamaha EQ's. There's one switch for the input atteenuation and one for the output. I think I understand why a person would have both set to +4dB or both set to -20dB. When would a person have the input set to -20dB and the output set to +4dB (or vice-versa)? Consumer theatre equipment and pro amps, or pro theatre equipment and consumer amps?


I guess if someone needs the extreme level differential mixed settings get, although it would be pretty unusual IMO.




Kix_N_Grins said:


> Here's something else that's been perplexing me the past week while trying to integrate the Mains & Subs...
> 
> When I use REW, play my turntable, or use a mp3 player, I'm routing the signals through a Beresford TC-7240 Line Level Audio Router. Basically, it's a nice A-B-C-D switch box that feeds into my AVP. I only have a total of 5 inputs on the AVP, and it's my way of having 3-4 line-level signals and only take up one input on the AVP.
> 
> However, when I listen to anything from my Samsung Blu-ray (You-tube, Netflix, etc) connected to my AVP via HDMI, the Mains are over-bearing and I can't hear the subs at all from the LP. So, I turn down the Mains using the input gain control on the Mains EQ until it "sounds right" to my ears.


 Almost sounds like some kind of high pass filter is in place. Check the menus on both the receiver and blu-ray. Might try another HDMI input on the receiver, of maye even another blu ray player to see if that makes a difference.

Regards, 
Wayne


----------



## Kix_N_Grins (Feb 14, 2015)

Thanks again for the help and tips, JT and Wayne.



jtalden said:


> Typically I would adjust the distance to provide the maximum SPL through the XO range (about 30-180Hz in this case).


With that in mind, I ran some more measurements tonight trying to maximize the SPL in that area while adjusting the Subs distance. I got a little improvement when I set them to 2 ft, but it wasn't much. I also tried switching the phase on both subs 180 degrees and trying different distances, which seemed much worse. My subs don't have pots for phase, just 180* switches. So, I'm just going to leave at 9ft for now, and keep in mind that it may be easier to EQ at 12ft (since it a little flatter in the XO range).



jtalden said:


> The noise is possibly a ground loop issue. I will let Wayne or someone with more experience help you with that type of problem. It shouldn't do that and it is best to identify the source of the problem and correct it.


Yes, I spent a couple months fighting ground loop problems last spring. I was able to reduce it greatly, but not 100%. After that, I fought some unknown issue with a Galaxy 140 SPL meter for another 4 months. I finally got frustrated and gave up. I figure I'm going to be moving from here in a couple years. I could spend a couple years trying to resolve the issues and not really learn anything about REW, or learn about REW and my equipment for a couple years and let the issues disappear when I move. 

I'm using a Jensen optic-isolator on my cable to my TV, all of my equipment is plugged into the same single wall outlet (using lots of power strips). The only thing that is connected to a different outlet is my PC for REW. I'm looking at buying a NAD 24bit DAC wireless tramsmitter/receiver to break that hard-wire connection.



Wayne A. Pflughaupt said:


> Almost sounds like some kind of high pass filter is in place. Check the menus on both the receiver and blu-ray. Might try another HDMI input on the receiver, of maye even another blu ray player to see if that makes a difference.


I'll look into those menu's next. I don't think I've really explored the menus on my Blu-ray yet



Wayne A. Pflughaupt said:


> I must say I’m impressed with your equipment list, Kix. You’re probably the only other person I know of who has more of those Yamaha EQs than I do. Must be an impressive looking rack!


Thanks, Wayne. I posted a picture of it below. It does look impressive to me, IMO. The pic doesn't do it justice. I had a hard time getting everything to fit in the oak cabinet. The cabinet used to have a fixed shelf at the top that wasn't covered by the glass doors. I had the fixed shelf removed and bought taller glass doors to cover the whole front. 

You can barely see one of my subs on the floor just to the right, and my mains/main assists are to the left. The bottom section of the cabinet holds my gear for sides and rear channels, the middle shelf is center channel and sub EQ, and the top shelf are for the main EQs/amps.

Kix


----------



## Kix_N_Grins (Feb 14, 2015)

So, is this the right time to begin EQing my Mains? 

If so, do I focus on the 60-400Hz area or do I expand the range to something more "full-range" (but focus more on 60-400Hz)? 

I think I read that I need to measure/equalize the left and right Main separately with the subs. Is this correct?

Thanks,
Kix


----------



## jtalden (Mar 12, 2009)

Kix_N_Grins said:


> Here's something else that's been perplexing me the past week while trying to integrate the Mains & Subs...
> 
> When I use REW, play my turntable, or use a mp3 player, I'm routing the signals through a Beresford TC-7240 Line Level Audio Router. Basically, it's a nice A-B-C-D switch box that feeds into my AVP. I only have a total of 5 inputs on the AVP, and it's my way of having 3-4 line-level signals and only take up one input on the AVP.
> 
> ...


Did you resolve this? The AVP manual shows an 'LFE Trim' setting (Page 34) to adjust the SW trim of the LFE channel level verses the redirected stereo to LFE signals. Try setting this to -10dB and see if that resolves the problem. There is another trim there as well 'Stereo+Sub' that may help if fine tuning is still needed. Possibly there is a setting of one or more of these controls in the AVP that will resolve the issue. I am not sure this is the issue and if you still have trouble an Outlaw Forum may be more helpful.

I would sort this out before full range EQ efforts.


----------



## Kix_N_Grins (Feb 14, 2015)

jtalden said:


> Did you resolve this? The AVP manual shows an 'LFE Trim' setting (Page 34) to adjust the SW trim of the LFE channel level verses the redirected stereo to LFE signals. Try setting this to -10dB and see if that resolves the problem. There is another trim there as well 'Stereo+Sub' that may help if fine tuning is still needed. Possibly there is a setting of one or more of these controls in the AVP that will resolve the issue.


Ahhh. I remember reading this when I got the AVP last year. Had no clue what it meant, but it's starting to make some sense now. I'll give it a try in the next day or so... I've always wondered why my cheap mp3 player always sounded more "solid" than my streaming signals from the blu-ray.

Thanks again, JT.

Kix


----------

