Need some help with room gain.

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Danzilla31

Audioholic Spartan
I am having some trouble I believe with room gain. When the bass gets heavy in music or music especially movies in grenade explosions and deeper stuff the sub from the right sub just sounds boomy or flabby too thick and it becomes more localizable. You can tell it's coming from the right side. Just a thick muddy almost grinding sound. At first I thought it was the driver but I'm not overpushing them at all. And when I sit to the far left on that left couch it sounds better.

I believe as you'll see in the picture I have posted with this that that corner where the wall comes out it's in is the issue.

This didn't use to happen when I had the PB 2000's but due to there smaller size I was able to move them closer to the center spot and away from that corner.

It was noticeable some in extended mode but it's very noticeable running them in standard mode. I've come to find that I love running these in standard. The way they sound opened up is just awesome in that big room.

I have 2 things I need help on.

The first is a list of the items I need to really begin to measure my room properly. Microphones software etc. I'm tired of operating in the dark here that room is complicated I just need to suck it up and learn how to do this. Just a brief list is all I need. Please be patient if I come back after operating the software and have some questions I'll be learning something new here.

The second question is about a possible solution. I could use your feedback on. I'm thinking of just moving them both behind the couches. Where I would place them would be behind the main 2 sweet spots on the inside seats of both couches. Why I am excited about this is because A) you guys know I prefer near field effect and B) I would get a massive amount of increase in output they'd be practically on top of each other. I could run them lighter put less stress on the driver. And point C) is I could get my PC 4000's and put them up front. With there smaller footprint I could easily keep the right one away from that corner. I get my quad subs and I get all 4 of them almost a perfect match in output and range and I get to keep them in the SVS family. I'm very loyal to them not just for performance but how they've treated me as a customer same With RSL. Those 2 companies are my favorite and wherever possible they will be the first place I spend my money

I still need that list and any feedback on my solution on point a b and c are greatly appreciated. Here's a pic of the setup. Bear in mind gentleman that although aesthetics are appreciated I'm a bachelor. Ultimately I don't care where the subs go it's about performance. Thank you very much for any time and input

20180915_202313.jpg
 
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shadyJ

Speaker of the House
Staff member
I would look into getting a UMIK-1 mic and a copy of REW (this assumes you have a laptop that you can use). REW is free but the UMIK will set you back probably a bit over 80 bucks after shipping. You need to go over a tutorial or two to get REW going with your mic, than make some measurements. Once you ave made your measurements, you can adjust the subs for a more preferable response. I wouldn't bother buying an outboard EQ, you have very good parametric equalizers onboard the PB-4000s. In the meantime, use the room gain compensation control on the SVS app to see if you can reduce some of the low end bloat.
 
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Danzilla31

Audioholic Spartan
I would look into getting a UMIK-1 mic and a copy of REW (this assumes you have a laptop that you can use). REW is free but the UMIK will set you back probably a bit over 80 bucks after shipping. You need to go over a tutorial or two to get REW going with your mic, than make some measurements. Once you ave made your measurements, you can adjust the subs for a more preferable response. I wouldn't bother buying an outboard EQ, you have very good parametric equalizers onboard the PB-4000s. In the meantime, use the room gain compensation control on the SVS app to see if you can reduce some of the low end bloat.
Ok I'll get on ordering those.
I did use the room gain compensation on the subs especially the one on the right it helped but it didn't remove all of it. And it's still localizable on that right hand side. I'm going to move those beasts tonight after I get back home put them behind the couches and see if that makes a difference as well. If it does I can then order the PC 4000's for the front.

Those are the ones I really want anyway to pair with them. So I'm hoping secretly that works

I'll still need the measuring tools whether I do that or not so thanks a lot for your help Shady!
 
D

Danzilla31

Audioholic Spartan
SVS gave me some good advice on running them diagonal that one since it sounds so good on the left just keep it there put the right one diagonal behind the couches. Options options I'll just have to see how this plays out
 
speakerman39

speakerman39

Audioholic Overlord
Dan, I was advised to get a CSL UMik1 b/c it can measure below 20 Hz. Here is a link should you be interested:

http://cross-spectrum.com/measurement/calibrated_umik.html

It looks like they are now $105 plus S&H. IIRC, the S&H cost me another $10. As Shady mentions, REW is free to download. This link should work for REW:

https://www.roomeqwizard.com/

BTW, did you level match the subs before calibration? Doing so is very important. Are you using Audyssey? Very nice looking setup! Congrats! :cool:


Cheers,

Phil
 
S

snakeeyes

Audioholic Ninja
Those UMIK mics work for kareoke? Asking for a friend. LOL :)
 
lovinthehd

lovinthehd

Audioholic Jedi
They're measurement mics! Why would you want to fill up a nice measurement mic with saliva? :) Define "work" otoh. :)
 
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shadyJ

Speaker of the House
Staff member
Those UMIK mics work for kareoke? Asking for a friend. LOL :)
The UMIK mics would be a terrible choice for karaoke. They have an omindirectional pickup pattern. They would constantly be getting into a feedback loop. That is the very last kind of microphone you want for that application. You need a directional cardioid mic for Karaoke. Just get something that was explicitly made for that application.
 
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snakeeyes

Audioholic Ninja
The UMIK mics would be a terrible choice for karaoke. They have an omindirectional pickup pattern. They would constantly be getting into a feedback loop. That is the very last kind of microphone you want for that application. You need a directional cardioid mic for Karaoke. Just get something that was explicitly made for that application.
Yep makes sense. Just making a joke. But karaoke would be fun. Like Jim Carrey in cable guy. :)
 
speakerman39

speakerman39

Audioholic Overlord
Yep makes sense. Just making a joke. But karaoke would be fun. Like Jim Carrey in cable guy. :)
Jim Carey in Me, Myself, & Irene was funnier inmho. Laughed my a$$ off on that one. But, man he has flipped his lid. Not sure what has happened to him, but he has flipped out. Seriously! :confused:

Cheers,

Phil
 
Matthew J Poes

Matthew J Poes

Audioholic Chief
Staff member
You might also try applying a lower crossover to the right sub and see what that does. It’s possible the sub peak causing the boom is higher in the bass region than you realize. By lowering the crossover it also effectively lowers the volume of the upper bass without touching the lower bass. Can sometimes help.

Also try flipping the sub around so the driver faces the wall or across the wall. The sub itself can be physically large enough that SBIR effects screw up an otherwise good response and the best fix is flipping it around.

I wrote an article for my group here:
https://www.avnirvana.com/threads/sbir-matters-for-subs-too.2269/ that shows an extreme example of it. If you follow along and look at all the measurements you can see what was going on.

One last thing to consider, if the phase of one sub is reversed as compared to the other, it can cancel bass in one region of the response and cause a boost in another. I’ve measured this in other people’s systems and found very boomy one-note bass. Literally a flip of the polarity totally fixed it. I didn’t notice this problem as coming from one side so I don’t suspect this is your problem, but you never know.

The measurement mic recommendation is a good one. I’m brand agnostic so I also suggest looking at the Dayton umm-6.

If budget allows the Cross Spectrum is nice, though I really wouldn’t worry too much about it. The correction to below 20hz isn’t that useful. It’s one of those things that I think serves more for bragging rights than practical usage. Get a mic, whichever one you can justify, download REW, and spend many sleepless nights seeking elusive flatness.
 
D

Danzilla31

Audioholic Spartan
You might also try applying a lower crossover to the right sub and see what that does. It’s possible the sub peak causing the boom is higher in the bass region than you realize. By lowering the crossover it also effectively lowers the volume of the upper bass without touching the lower bass. Can sometimes help.

Also try flipping the sub around so the driver faces the wall or across the wall. The sub itself can be physically large enough that SBIR effects screw up an otherwise good response and the best fix is flipping it around.

I wrote an article for my group here:
https://www.avnirvana.com/threads/sbir-matters-for-subs-too.2269/ that shows an extreme example of it. If you follow along and look at all the measurements you can see what was going on.

One last thing to consider, if the phase of one sub is reversed as compared to the other, it can cancel bass in one region of the response and cause a boost in another. I’ve measured this in other people’s systems and found very boomy one-note bass. Literally a flip of the polarity totally fixed it. I didn’t notice this problem as coming from one side so I don’t suspect this is your problem, but you never know.

The measurement mic recommendation is a good one. I’m brand agnostic so I also suggest looking at the Dayton umm-6.

If budget allows the Cross Spectrum is nice, though I really wouldn’t worry too much about it. The correction to below 20hz isn’t that useful. It’s one of those things that I think serves more for bragging rights than practical usage. Get a mic, whichever one you can justify, download REW, and spend many sleepless nights seeking elusive flatness.
Thanks for the advice I've been on your forum browsing around I really like avnirvana I've read some of your reviews and posts and enjoy your articles and advice. Its a nice forum has the same friendly vibe as here I think I'll be registering over there and getting to know you guys. Although is always my home base. Good to meet you!
 
D

Danzilla31

Audioholic Spartan
You might also try applying a lower crossover to the right sub and see what that does. It’s possible the sub peak causing the boom is higher in the bass region than you realize. By lowering the crossover it also effectively lowers the volume of the upper bass without touching the lower bass. Can sometimes help.

Also try flipping the sub around so the driver faces the wall or across the wall. The sub itself can be physically large enough that SBIR effects screw up an otherwise good response and the best fix is flipping it around.

I wrote an article for my group here:
https://www.avnirvana.com/threads/sbir-matters-for-subs-too.2269/ that shows an extreme example of it. If you follow along and look at all the measurements you can see what was going on.

One last thing to consider, if the phase of one sub is reversed as compared to the other, it can cancel bass in one region of the response and cause a boost in another. I’ve measured this in other people’s systems and found very boomy one-note bass. Literally a flip of the polarity totally fixed it. I didn’t notice this problem as coming from one side so I don’t suspect this is your problem, but you never know.

The measurement mic recommendation is a good one. I’m brand agnostic so I also suggest looking at the Dayton umm-6.

If budget allows the Cross Spectrum is nice, though I really wouldn’t worry too much about it. The correction to below 20hz isn’t that useful. It’s one of those things that I think serves more for bragging rights than practical usage. Get a mic, whichever one you can justify, download REW, and spend many sleepless nights seeking elusive flatness.
hmmm I have the Denon X4400h it has Audyssey it calibrated my subs before it runs Audyssey. Do you or anyone know how I would lower the crossover on that individual sub? Not sure if the Denon allows me to do that. Although it could be something I missed.
 
D

Danzilla31

Audioholic Spartan
Dan, I was advised to get a CSL UMik1 b/c it can measure below 20 Hz. Here is a link should you be interested:

http://cross-spectrum.com/measurement/calibrated_umik.html

It looks like they are now $105 plus S&H. IIRC, the S&H cost me another $10. As Shady mentions, REW is free to download. This link should work for REW:

https://www.roomeqwizard.com/

BTW, did you level match the subs before calibration? Doing so is very important. Are you using Audyssey? Very nice looking setup! Congrats! :cool:


Cheers,

Phil
The Denon X4400H I have will level match the subs before it runs Audyssey. I've been very pleased with Audyssey it has done a good job with consistent results in my room.

Thanks for the compliments yeah it's a work in progress but that room is coming along.
 
lovinthehd

lovinthehd

Audioholic Jedi
The 4400 can adjust delay/level for different subs, not provide different crossovers. Unless he means to also use the lpf on the sub? Dunno of any avr that allows separate crossover control for different subs since that would conflict with the speakers between the two subs, unless the avr had separate lpf for sub (which I can't think of any units that do that either).
 
D

Danzilla31

Audioholic Spartan
Hey guys thanks for all the great advice so far. You guys have given me some great options to try before I try and lug these monsters around the room. I'll give some of these a shot and let you know how it goes.
 
speakerman39

speakerman39

Audioholic Overlord
The Denon X4400H I have will level match the subs before it runs Audyssey. I've been very pleased with Audyssey it has done a good job with consistent results in my room.

Thanks for the compliments yeah it's a work in progress but that room is coming along.
Yeah I prefer Audyssey as well. The XT 32 W/Sub HT EQ really makes a difference. Getting dual subs dialed in properly is a lot of work. I can not even tell you how many times I had to run and then re-run Audyssey to only run yet again. It was so bad I was literally doing it in my sleep. No kidding! Just keep at it and you will get there. :)


Cheers,

Phil
 
Last edited:
D

Danzilla31

Audioholic Spartan
The 4400 can adjust delay/level for different subs, not provide different crossovers. Unless he means to also use the lpf on the sub? Dunno of any avr that allows separate crossover control for different subs since that would conflict with the speakers between the two subs, unless the avr had separate lpf for sub (which I can't think of any units that do that either).
Yeah I didn't think there was a way maybe he meant lowering the crossovers on the front speakers that would do the same thing right?
 

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