What to do about a 10x10 "bassy" room

[ParadigmDawg]

Cant wait until mine arrive. The wife thinks she will like the wooden frames.

And quickly becoming the number 1 seller may I add!

Glenn

 

[bpape]

Just FYI, we do offer a wide variety of cloth for the panels. We have stock colors in standard, Guilford FR701, and one of the other Guilford patterns. We can, however, get any of the Guilford cloths with a variety of colors an patterns but the cost can vary significantly depending on which you select.

In any case, it's a far better solution to putting posters or anything else reflective on them.

Bryan

 

[rufas2000]

One more question: Since I have a door next to the left back wall I can't put a bass trap in prime position. I have no such issue on the right back wall. Should the priority be having each trap in the best position I can regardless of whether they "match" or is it better if both rear corner traps are set up identically?

Thanks.

 

[bpape]

In the rear, you can slide by with non-symmetry. In the front, symmetry is key. If we can deal with what the room needs without introducing non-symmetry all the better. If we need to deal with that back corner - then it's not a killer.

Bryan

 

[rufas2000]

I'll try it both ways. I prefer symmetry so I'll start from that point. Then I can try it the other way and hear the results.

I realize I'll have to experiment anyway as every room is different (as is every set of ears). But I ask questions in order to have a firm grasp of acoustic principals and how these panels & traps work (so I don't put posters on absorbers LOL). That way I have a good starting point.

So now I'm waiting for my 6 242s. After the improvements of the Tritraps I can't wait to hear what the 242 panels will do. I've known for awhile that my room was the number 1 enemy of great sound and now the solution is in my grasp. I suspect I'll hear music in a way I never have before. I already am to an extent.

 

[ParadigmDawg]

Check out these babies that just arrived!

I'll try it both ways. I prefer symmetry so I'll start from that point. Then I can try it the other way and hear the results.

I realize I'll have to experiment anyway as every room is different (as is every set of ears). But I ask questions in order to have a firm grasp of acoustic principals and how these panels & traps work (so I don't put posters on absorbers LOL). That way I have a good starting point.

So now I'm waiting for my 6 242s. After the improvements of the Tritraps I can't wait to hear what the 242 panels will do. I've known for awhile that my room was the number 1 enemy of great sound and now the solution is in my grasp. I suspect I'll hear music in a way I never have before. I already am to an extent.

 

[rufas2000]

Check out these babies that just arrived!

Showoff!!! (LOL)

Seriously, they look good. I couldn't afford those and I don't have a wife to have to please with the decor.

Hope you enjoy them.

 

[rufas2000]

Once the 242s were attached to their stands I noticed a dramatic difference in sound. It didn't kill the echo but put it on life support. Much better. Now on tap are the two 244s for the back. And that may about do it. Or maybe a monster trap for the middle of the rear wall.

Curiousity: I had the 242s in the room leaning against the wall before they were attached to their stands. They were not nearly as effective as they were once they were attached to the stands. Anybody know why?

Thanks.

 

[bpape]

You have more absorbtion up around your ear level and where other reflections (2nd and 3rd) can't form. Also, you should take note of where your early reflection points are and make sure the 242's cover them. You'll have one on each wall for each speaker for each seat.

244's vs Monster on the rear wall:

It's a tradeoff. The Monster will reach deeper. On the other side, 244's will cover more area. It's hard to say since the room isn't that big and the primary axial modes aren't WAY down deep.

Bryan

 

[peerlesser]

One of the easiest ways to control global axial room modes is still with DSP applications such as BFD or the new fully automatic subwoofer precision-EQ "dspeaker Anti-Mode 8033".

They really make a difference and the latter is a no-brainer to install. Both cost about the same (<300$)

 

[bpape]

If all of your problems happen to be peaks instead of nulls, EQ will work. If they're nulls and/or decay time related, EQ won't work.

Bryan

 

[peerlesser]

If all of your problems happen to be peaks instead of nulls, EQ will work. If they're nulls and/or decay time related, EQ won't work.

Bryan

Thats correct, but the "boomy" high-Q standing wave peaks are usually the most annoying part. That DSPeaker Anti-Mode 8033 will decrease their decay times very efficiently as it corrects both frequency and time domain (unlike some EQs). Using both acoustic solution and DSP is the best way, as the DSPs can not be used to counter-model higher frequencies where everything is local. For lowest ranges from 16 to 80Hz that DSP is way more efficient and cheaper than any reasonable amount of acoustical damping that could be filled to a living room. That product has only been on market for one month and not many knows about it. In Europe it has been very successful amongst users (including me).

 

[mike c]

That product has only been on market for one month and not many knows about it. In Europe it has been very successful amongst users (including me).

what a coincidence ... new product ... new you!

 

[peerlesser]

what a coincidence ... new product ... new you!

Yeah I know

In past I opposed all DSP based EQs and preferred only acoustic damping as it is usually considered the best investment in the whole HT system. With damping I couldn't get more than 5-6dB attenuation to highest modes around 55Hz when I clearly needed about 15dB. I have quite difficult and small concrete room. That little black box just actually worked those worst modes down 15dB, so I could claim it became my best investment. Same results or better could probably be achieved with BFD, but its too difficult to set up as it needs computer with decent sound card. Also it would require ECM8000 or equivalent mic and balanced XLR to RCA conversion because these are not included with it. That new box had included mic and it operates with RCA input and output.

I did get results quite close to those examples of the manufacturer (I had maybe 2-3dB more variation)
http://www.dspeaker.com/en/support/anti-mode-technology/measurements.shtml

I dont know if that box is sold to the US anyway so advertising it would generally be useless.

 

[bpape]

Agreed. If you have a stubborn peak that you can't get rid of, an EQ can work. But please, don't tell people that you can fix decay times with EQ - you can't. You can VERY SLIGHTLY impact ringing at a frequency if you get the center frequency, Q, etc. EXACTLY correct. If you're off even a little, you can actually cause MORE ringing at other frequeneis.

A proper solution is to do what you can to deal with frequency response and decay times via proper placement of seating and speakers (and sub) in conjunction with a proper treatment regimine. This doesn't mean just throwing slabs at every corner. There are a lot of other things in the room that need to be dealt with that won't be addressed in corners.

THEN, once the decay time is in the appropriate range, you can look at the FR and see if there are a couple of peaks that can be knocked down via some judicious use of EQ. If you EQ first and then look at the decay time and try to fix it, you'll end up chasing your tail as you'll be missing what really needs to be treated and constantly going back and adjusting the EQ.

Just my 2 cents.

Bryan

 

[peerlesser]

You can VERY SLIGHTLY impact ringing at a frequency if you get the center frequency, Q, etc. EXACTLY correct. If you're off even a little, you can actually cause MORE ringing at other frequeneis.

Bryan

Getting the parameters right is exactly why that box works so well. With SMS-1 the resolution is not enough as it is only 1Hz. It also needs some hand-tweaking to get good results. 8033AM is more accurate and uses custom z-plane design AMFs instead of normal biquad IIR notching filters, so the late reverbation at mode frequency is suppressed slightly better than normal EQs if the subwoofer is placed in to the corner. This way it has less linear phase shift compared to the pressure maximum of axial mode and the AMF-type attenuation works longer in time-domain. Of course one problem in exact parameters is changes in temperature and pressure, which will affect to the speed of sound and further center frequencies (especially high ones).

It is true that EQs don't much affect 60dB decay times, but if you look at that case 1 in the posted link to measurements, there is serious difference in the 20 dB attenuation times. That is what makes significant audible difference, and it would be difficult or impossible to achieve with only acoustic damping. I would still say that in a 10x10 bassy room, whatever you do will not have the same improving impact than doing that sort of EQ (evaluating both audible difference and measured response).

 

[bpape]

Yes. If you get it exactly right in center frequency and Q, it can help some. How does one go about doing this for 2 rows of 3 seats which all have different peaks and nulls? You can't - unless it's purely height related and a peak instead of a null.

In general, a combination of treatment and EQ is generally the best course of action.

Bryan

 

[peerlesser]

Yes. If you get it exactly right in center frequency and Q, it can help some. How does one go about doing this for 2 rows of 3 seats which all have different peaks and nulls? You can't - unless it's purely height related and a peak instead of a null.

In general, a combination of treatment and EQ is generally the best course of action.

Bryan

Locality is one of the problems indeed. Fortunately, axial modes have rather constant center frequencies in such small rooms where they are the biggest storage of energy. I used the gradient algorithm in 8033AM which is meant to optimize between multiple measurement points and separate axial modes from tangential and oblique modes. Although q values varied, the error can be weighted smartly to carentee all seats equal improvement. It worked well for me as the worst standing wave is perpendicular to seat rows. I still used acoustic treatment but it improved mostly the higher frequency decay time and stereo image by damping the direct 1st and 2nd order early reflections.

 

[bpape]

Have you ever looked at the decay times at each seat when the average Q is used? Also, how does one get the room and ears to ignore the tangential and oblique modes?

How does the algorithm work when you have a peak at a frequency in one row and a null in the other row? Proper treatment can help minimize this.

If treatment didn't impact your decay times in the bottom end, then one or more of the following is the issue:

- Treatment not thick enough
- Treatment not placed in the correct places
- Not enough treatment was used to reach the target decay time for that specific room in that specific application

Again, I'm not saying not to use EQ. EQ has it's place. It's one part of properly addressing room acoustics but it can't do it by itself. Heck, I sell treatments and I use EQ - on my sub only. I have 5 parametric bands all set below 50Hz.

Quite honestly, the biggest thing you can do to help yourself in terms of frequency response requires no purchase of treatments or EQ. It's very careful placment of seating, speakers, and sub coupled with proper xover frequency, slope, and phase adjustment.

We can treat and EQ till we're blue in the face but if the sub is in a corner and the seating is slammed against a wall behind it, there's only so much that can be done.

Bryan

 

[rufas2000]

OK got the 244s. Everything is getting better. still think I could get better still but I'm maxed on treatments, there just isn't enough wall left to store my CDs and DVDs along with the panels. Here is what I got:

Speakers:
5 feet apart from one another (at their end point). Toed in toward me but not directly pointing at me. 18-24 inches away from the side wall, 12-18 inches from the back wall. These are approximates, the range accounts for the back / right side of the speaker being closer to the wall than the front / left.

242s:
I have 6 of them. Two are placed to each side right at the front edge of each speaker. Two are placed behind the speaker to where the panel is behind about half of each speaker. The final two are placed in the back next to one another. Also, I'm glad to read that a sub in a corner is not the optimal placement as I only have room toward the middle between the two fronts for one.

Tri Traps:
One in each of the front 2 corners

244s:
One on the back corner to my right nestled in the corner (kinda like a tritrap) and the other one leaning against the left back wall. There is a door there so I cannot place it in the corner. Neither are on stands as the one by the door cannot be placed in a corner without blocking the door from being open.

Chair:
Six and a half feet from the front of the room, two feet from the back.

EQ:
None right now. Audyssey did not produce a pleasing result for me.

The only rugs are in the front under the two front speakers.

So are there any suggestions on what might make the sound even better. Once I got the 244s in the back vocals were definitely improved. Detail was improved but bass was still dominant. Perhaps its the rock / metal music I'm playing.

Thanks.

BTW: Should I get a sub for the low end and crossover my speakers at 80 Hz or so? If my main issue is an abundance of bass wouldn't a sub make it worse? Or will it make the bass cleaner and more desirable. Seems a shame to not use my Klips powerful bass drivers.