Skip to main content ↑ ↓

Notice

Please note that most of the software linked on this forum is likely to be safe to use. If you are unsure, feel free to ask in the relevant topics, or send a private message to an administrator or moderator. To help curb the problems of false positives, or in the event that you do find actual malware, you can contribute through the article linked here.
Topic: Acoustic treatment (Read 17921 times) previous topic - next topic
0 Members and 1 Guest are viewing this topic.

Acoustic treatment

Reply #25 –
Quote from: probedb on
The center speaker looks too big for the room to me. You might find the rear speakers at the side of you work better too, they should really be lower according to what Dolby/DTS recommend but whatever works for you.


Good points.  That center channel speaker looks to me more like a sound bar.  I'd like to  know what make and model.

Quote
Arnold, it's a fairly typical size for flats/apartments in the UK, but it's even closer than I had my setup in a flat


Well, you know about us Americans. ;-)

My wife and I find just enough space in a stand alone house barely under 3000 square feet. 

My listening room was apparently significantly larger than that when we lived in Bavaria, long ago when I was just a humble GI.

If I had that few square feet it would probably be all one room, or two merging the listening room with the food prep/eating area.

Acoustic treatment

Reply #27 –
Quote from: probedb on
The center speaker looks too big for the room to me. You might find the rear speakers at the side of you work better too, they should really be lower according to what Dolby/DTS recommend but whatever works for you.

Arnold, it's a fairly typical size for flats/apartments in the UK, but it's even closer than I had my setup in a flat


I had the larger Paradigm Studio 100 v5 floor standers that I reluctantly sold when I moved to my apartment, so my Studio 20's (the bookshelves) are doing front duties for now.

The center speaker, CC690, is probably the best I've ever heard for dialog intelligibility. I've had the CC590, the smaller center, and there is some weird notch in the upper midrange that causes dialog to sound a little honky which is absent on the 690.

Although the center is high-passed at 70 Hz right now, feeding the low bass from all channels to 2 SVS SB1000 subs.

Acoustic treatment

Reply #29 –
Quote from: greynol on
I hope the pictures at least lay to rest the absurd discussions about amplifiers.


I've disconnected the power amp. Doesn't serve much purpose. Only running a Marantz SR6008 receiver and in my size space, I can't imagine wanting/needing more than that.

Acoustic treatment

Reply #30 –
Quote
The center speaker looks too big for the room to me. You might find the rear speakers at the side of you work better too, they should really be lower according to what Dolby/DTS recommend but whatever works for you.


I'm using dipole surrounds. Unfortunately my room is a compromise. I know that, so I'm just trying to best manage the problems I have.

I couldn't mount the dipoles on either side of the panels as I don't have enough space for that, so my only option was to mount them above.

Surround sound is, in a word, fantastic, despite the imperfect positioning which was my biggest fear, together in close proximity to the absorption panels. My fears were laid to rest once I put on Transformers.

Acoustic treatment

Reply #31 –
Quote from: Rich B on
Quote
Good points. That center channel speaker looks to me more like a sound bar. I'd like to know what make and model.


Not a sound bar.


The make and model makes that clear.

It is one heck of a center channel speaker, not that there is anything wrong with that since the center channel can end up carrying the larger part of the acoustic load in many systems.

On the lighter side, with its current configuration of six (6)! drivers it is just a midrange and tweeter shy of having enough drivers to be a very  serious sound bar! ;-)

Corrected picture:

Quote

Acoustic treatment

Reply #32 –
Quote from: Arnold B. Krueger on
Driven hard, or overdriven?

I wouldn't know. If you define "overdriven" as "exhibits wind noise" then I guess they were overdriven, but then we are arguing a tautology.

Back in the day when I was clicking around in speaker simulation software it was always a challenge to keep both the port dimensions and the air speed in check. Usually, when the chassis were driven at their rated power, the simulation would show air speeds exceeding the recommended threshold many times over.

Anyway, the ports on Rich's speakers are located at the front, so this point is moot anyway.

Quote from: krabapple on
Hmm, don't actual theaters use...subwoofers? 
Yes, but only because they're cheap and lazy. 

Acoustic treatment

Reply #33 –
Quote from: Gecko on
Quote from: Arnold B. Krueger on
Driven hard, or overdriven?

I wouldn't know. If you define "overdriven" as "exhibits wind noise" then I guess they were overdriven, but then we are arguing a tautology.


Exactly what constitutes overdrive should logically be based on the speaker's power handling ratings. Of course those are often mystery meat.

My point is that power amps are cheap and powerful, recordings with powerful bass are plentiful, and building a conventional passive speaker that can't be overdriven may be mission impossible.

Quote
Back in the day when I was clicking around in speaker simulation software it was always a challenge to keep both the port dimensions and the air speed in check. Usually, when the chassis were driven at their rated power, the simulation would show air speeds exceeding the recommended threshold many times over.


It's the old size versus salability problem.

Quote
Anyway, the ports on Rich's speakers are located at the front, so this point is moot anyway.


His speakers seem to be pretty competent.  It is possible that the majority of the energy ends up in that presumably unported center channel.

Quote
Quote from: krabapple on

Hmm, don't actual theaters use...subwoofers? 

Yes, but only because they're cheap and lazy. 


That's what some advocates of so-called full range speakers would like us to believe. IMO it is yet another example of the anti-engineering bias in high end audio as we know it today.  The same problem as we see being played out in the Pono.

Acoustic treatment

Reply #34 –
Quote from: Arnold B. Krueger on
Quote from: Gecko on
Quote from: Arnold B. Krueger on
Driven hard, or overdriven?

I wouldn't know. If you define "overdriven" as "exhibits wind noise" then I guess they were overdriven, but then we are arguing a tautology.


Exactly what constitutes overdrive should logically be based on the speaker's power handling ratings. Of course those are often mystery meat.

My point is that power amps are cheap and powerful, recordings with powerful bass are plentiful, and building a conventional passive speaker that can't be overdriven may be mission impossible.

Quote
Back in the day when I was clicking around in speaker simulation software it was always a challenge to keep both the port dimensions and the air speed in check. Usually, when the chassis were driven at their rated power, the simulation would show air speeds exceeding the recommended threshold many times over.


It's the old size versus salability problem.

Quote
Anyway, the ports on Rich's speakers are located at the front, so this point is moot anyway.


His speakers seem to be pretty competent.  It is possible that the majority of the energy ends up in that presumably unported center channel.

Quote
Quote from: krabapple on

Hmm, don't actual theaters use...subwoofers? 

Yes, but only because they're cheap and lazy. 


That's what some advocates of so-called full range speakers would like us to believe. IMO it is yet another example of the anti-engineering bias in high end audio as we know it today.  The same problem as we see being played out in the Pono.


Sorry I'm not following. Are you saying the use of subwoofers is sort of frowned upon in high end audio? Or? If so, I agree although I'm not sure why that would be.

Acoustic treatment

Reply #35 –
Quote from: Rich B on
Are you saying the use of subwoofers is sort of frowned upon in high end audio?


Yes.

Quote
If so, I agree although I'm not sure why that would be.


I think that subwoofers tend to be frowned on by the high end fraternity because:

(1) They represent a fundamental technological change to audio. Look at how the high end is still struggling with the last few big fundamental technological changes to audio being:

(a) Non-traditional media and distribution

(b) Digital audio

© Solid State.

(2) Subwoofers can easily be a cost effective strategy for audibly higher performance at a lower system cost. In short, the high end as we know it today is largely about anti-science and anti-engineering.

Acoustic treatment

Reply #36 –
Quote from: Arnold B. Krueger on
Quote from: Rich B on
Are you saying the use of subwoofers is sort of frowned upon in high end audio?


Yes.

Quote
If so, I agree although I'm not sure why that would be.


I think that subwoofers tend to be frowned on by the high end fraternity because:

(1) They represent a fundamental technological change to audio. Look at how the high end is still struggling with the last few big fundamental technological changes to audio being:

(a) Non-traditional media and distribution

(b) Digital audio

© Solid State.

(2) Subwoofers can easily be a cost effective strategy for audibly higher performance at a lower system cost. In short, the high end as we know it today is largely about anti-science and anti-engineering.


I've heard arguments being thrown around that full range speskers have better integration between the bass, mids and tops relative to a sub, if used with a high-pass filter.

I think that may also play a factor in the perception that subs are not or should not be used in a high-end audio system. Especially two channel users will scoff at the idea of using a sub.

I know someone that has Vivid Audio G1 floor standers (on Stereophile, I think they considered them to be one ofthe 'best' speakers in the world, and he has two SVS SB13 Ultras, and he isn't missing their contribution because the G1's can reportedly handle 20 Hz at high levels.

Not sure how true that is. I think there is a perception in the high end world that using a crossover degrades sound quality for some reason.

Acoustic treatment

Reply #37 –
Quote from: Rich B on
I've heard arguments being thrown around that full range speakers have better integration between the bass, mids and tops relative to a sub, if used with a high-pass filter.


This comment looks to me like yet another audiophile hypergenerality.  The real question behind it relates to deciding on a good frequency for crossing the channel-related speakers to the shared subwoofer array.  That depends on the room acoustics and speaker placement. Proceeding logically, once we figure out what the required dynamic range and bass extension of the channel-related speakers is, appropriate channel-related speakers should be obtained.

Quote
I think that may also play a factor in the perception that subs are not or should not be used in a high-end audio system. Especially two channel users will scoff at the idea of using a sub.


IME 2 channel high enders tend towards irrational levels of conservatism. That said, my personal best system is fundamentally a 2 channel system. But this is me - I've had a sub and a center channel speakers since the 1980s.  Yup, 3 Ohm F's and a Cerwin Vega 18" driver that was rescued from an Earthquake theater system and reconed.

Quote
I know someone that has Vivid Audio G1 floor standers (on Stereophile, I think they considered them to be one ofthe 'best' speakers in the world, and he has two SVS SB13 Ultras, and he isn't missing their contribution because the G1's can reportedly handle 20 Hz at high levels.


The G1s strike me as yet another speaker with built in subwoofers. However the lowest crossover appears to be 220 Hz which may be high from the standpoint of lowest possible distortion. Since Stereophile ignores the existence of loudspeaker dynamic range issues (which are huge and audible!), their technical tests seem to be inadequate evidence to base a study of the issue at hand.  Their subjective evaluations are so poorly done that they are not even proper tests. The credibility of their staff is being called into question all over the web, and for what appear to be very good reasons. Sic Transit Gloria.

Quote
Not sure how true that is. I think there is a perception in the high end world that using a crossover degrades sound quality for some reason.


In the case of the Vivid G1s, the crossover is right there in the speakers themselves.  It seems well enough designed, so that isn't a problem but its very existence denies the validity of the above claim.  Yet another poorly-informed audiophile hypergenerality, I fear. 

One very serious problem with so-called full range speakers is that they force the subwoofer function and the rest of the speaker system to co-exist in one package, eliminating all kinds of potentially helpful speaker placement and upgrade options.

Acoustic treatment

Reply #38 –
Okay, so we established my room is a compromise. I knew that going in.

So my questions are - without measuring yet, have I basically done all I can to the room to improve the sound?

From my point of view, I have the following I can do, and you guys can agree/disagree with my logic :

1) Space the front and rear panels away from the walls by 3-4", for additional absorption down low
2) Install absorbers, perhaps 1 at the ceiling/wall point above the TV, in the front of the room, and at the rear

3) Tackle the wall/floor corners with some form of soffit.

4) Employ DSP for the very low frequencies

As things stand, I notice that there is still some ringing above 80 Hz. The quality of sound in the space is, in my opinion, fantastic for the most part, but it can be improved further.

I guess I just don't know to what extent I can still improve things within my room. Suggestions would be appreciated.

Acoustic treatment

Reply #39 –
Quote from: Rich B on
Okay, so we established my room is a compromise. I knew that going in.


Don't take it personally - all rooms are acostic compromises. ;-)

Quote
So my questions are - without measuring yet, have I basically done all I can to the room to improve the sound?


Measurements are proxies for listening, so how far you can get without them depends on the quality of your listening.

Quote
From my point of view, I have the following I can do, and you guys can agree/disagree with my logic :

1) Space the front and rear panels away from the walls by 3-4", for additional absorption down low


If you play with the model I posted a link to, you'll probably find that the performance of a porous absorber is optimized when the air space behind the absorptive element is about the same as its thickness.

I don't think your recent description described optimized absorbers, so optimizing them is a good first step.

Quote
As things stand, I notice that there is still some ringing above 80 Hz. The quality of sound in the space is, in my opinion, fantastic for the most part, but it can be improved further.


I wouldn't call audible ringing fantastic sound, but your proposed absorber reconfiguration could help.

Echo following comment about good sound usually being the result of a strategic combination of reflection, diffusion, and absorbency.  Reflection is usually free, absorbency can cost serious  money, but diffusion is usually the most costly.  OTOH it is often amazing what can be done with primarily diffusion.

Acoustic treatment

Reply #40 –
Quote from: Rich B on
Okay, so we established my room is a compromise. I knew that going in.

As are most home listening situations. No shame in that.

If I was in your situation, I would get some measuring kit to pin down any potential problems and specifically address those issues. I would NOT put more damping in the room without good reason. Too much damping will sound unnatural.

Some loose thoughts:
- Consider that professional studios combine absorbers and diffusors.
- It appears as though all dampening is happening at the front and in the back; nothing at the sides?
- The setup looks asymmetric. Your speakers appear to be shifted left of center wrt the room. On the left-side there is lots of glass, which is a great sound-reflector. We can't see what's on the right but I assume it's some furniture and a regular wall. The sound reflected from the left will be different from the sound reflected from the right (timing, different comb filtering effects, interaction with furniture). Is it possible to improve the symmetry?
- DSP is great, but IMO is only effective if you can measure the results of your efforts. As anyone who has played around with this will tell you: taking proper measurements, interpreting the results and making according adjustments to your DSP requires knowledge, skill and patience. You wouldn't be the first to give up in frustration. On the other hand, modern automatic room correction systems found in AVRs are pretty good (e.g. Audyssey MultEQ XT32).

Acoustic treatment

Reply #41 –
Quote
I wouldn't call audible ringing fantastic sound, but your proposed absorber reconfiguration could help.
|

No man, you clearly didn't read properly. I said I can still hear some ringing above 80 Hz, but for the most part, it sounds fantastic. What that means is that certain frequencies, above 80 Hz, are taking longer to decay. That won't ruin my enjoyment, but I would love to pin down exactly where the ringing is and hopefully address it. I never said audible ringing was fantastic or anything of the sort.

Quote
Echo following comment about good sound usually being the result of a strategic combination of reflection, diffusion, and absorbency. Reflection is usually free, absorbency can cost serious money, but diffusion is usually the most costly. OTOH it is often amazing what can be done with primarily diffusion.


So what do you suggest? I put diffusers in front of the absorption panels in the rear? My thinking is that given my small size space, I needed the thickest porous absorbers I could find, but diffusers (to my knowledge) don't work very well down to 100 Hz. I'm not sure how I would incorporate diffusers into my room, but any suggestions are welcome.

Acoustic treatment

Reply #42 –
Quote from: Gecko on
Quote from: Rich B on
Okay, so we established my room is a compromise. I knew that going in.



If I was in your situation, I would get some measuring kit to pin down any potential problems and specifically address those issues. I would NOT put more damping in the room without good reason. Too much damping will sound unnatural.


I ordered a UMIK-1 for measuring with REW. Still waiting for it.

Quote
Consider that professional studios combine absorbers and diffusors.


Every acoustic expert I've so far discussed this with has told me that diffusion will not work effectively in my space size. That I need a certain distance in order for the diffusers to actually work properly.

Quote
It appears as though all dampening is happening at the front and in the back; nothing at the sides?


Well I have a thick curtain to my left - I can't put a panel there obviously. To my right is my kitchen, and I really can't treat reflections there either.

Quote
The setup looks asymmetric. Your speakers appear to be shifted left of center wrt the room. On the left-side there is lots of glass, which is a great sound-reflector. We can't see what's on the right but I assume it's some furniture and a regular wall. The sound reflected from the left will be different from the sound reflected from the right (timing, different comb filtering effects, interaction with furniture). Is it possible to improve the symmetry?


It is asymmetric.  My room is asymmetric. You are right, I have glass on my left and on my right is my kitchen, albeit a small kitchen. What little wall I have on my right is covered with tiles and I won't be allowed to touch that zone. I'm not sure how to improve symmetry short of buying a new room. LOL.

Quote
DSP is great, but IMO is only effective if you can measure the results of your efforts. As anyone who has played around with this will tell you: taking proper measurements, interpreting the results and making according adjustments to your DSP requires knowledge, skill and patience. You wouldn't be the first to give up in frustration. On the other hand, modern automatic room correction systems found in AVRs are pretty good (e.g. Audyssey MultEQ XT32).


Yeah, I have Audyssey Mult EQ XT built into my Marantz AVR. Problem is, I don't like what it does to the rest of the frequency range. I would prefer targeted EQ to handle the very low bass issues only without it touching the mids or high-end range. I seen a few correction systems that I think would work well - Dirac seems to work very well, if reports are to be believed over at AVSforum.

Acoustic treatment

Reply #43 –
Quote from: Rich B on
To the acoustic experts :

Is there any benefit in placing acoustic treatment behind speakers? I have two broadband panels placed behind my main speakers because it was recommended by GIK acoustics

My room is fairly small and my speakers are positioned quite close to the wall. Now they never explained the merits behind it so I just assumed it would be beneficial.

I also have panels on the rear wall. I get why treatment should be used on the walls floor and ceiling to treat reflections, but why behind the main speakers?

Has anyone here put acoustic treatment behind their speakers and did it improve anything?



It is common to treat the front wall in studios, that practice is is getting copied in listening rooms. Looking at your pictures, though since you have have rear surrounds firing toward the front wall, it is helpful to reduce the refections from the sound channels bouncing off the front wall back to you.

On the question of diffusion, you are too close to the rear wall use diffusion there. If you really had to use diffusion RPG BAD panels are the only thing I can think off that might work. I have used them closer then any other diffusion but not as close as you would.



Acoustic treatment

Reply #44 –
Quote from: Rich B on
So what do you suggest?


If sound quality is really all that important to you, find a space where you can built a conventional listening room.

Quote
I put diffusers in front of the absorption panels in the rear?


Diffusion would probably be more effective in the front and the sides.

Quote
My thinking is that given my small size space, I needed the thickest porous absorbers I could find, but diffusers (to my knowledge) don't work very well down to 100 Hz.


Porous diffusers need to be really thick to be effective below 100 Hz. In your case sufficient thickness might exacerbate the obvious lack of space.

If your dream is building an anechoic chamber, I don't want to get in the way of your dreams, but most find anechoic chambers a lot weird sounding.

Quote
I'm not sure how I would incorporate diffusers into my room, but any suggestions are welcome.


Trying to obtain good sound quality in such a tight space is really challenging.

Acoustic treatment

Reply #45 –
Quote from: Arnold B. Krueger on
Quote from: Rich B on
So what do you suggest?


If sound quality is really all that important to you, find a space where you can built a conventional listening room.


Right, so you suggest I buy a bigger house. Thanks for that useless bit of advice, Arnold.

Quote
If your dream is building an anechoic chamber, I don't want to get in the way of your dreams, but most find anechoic chambers a lot weird sounding.


Who said anything about wanting an anechoic chamber??? This is the second time you have made really strange statements here. Perhaps you aren't the best person to be giving advice on the topic of acoustics. I have 8 acoustic panels in my room. Hardly an anechoic chamber!

Quote
Trying to obtain good sound quality in such a tight space is really challenging.


Gee, well thanks for nothing.  I may as well have not asked you to reply.

Acoustic treatment

Reply #46 –
Quote from: Rich B on
Quote from: Arnold B. Krueger on


Quote from: Rich B on

So what do you suggest?
Quote

If sound quality is really all that important to you, find a space where you can built a conventional listening room.


Right, so you suggest I buy a bigger house. Thanks for that useless bit of advice, Arnold.


There is a point there that might require some reflection to perceive. You seem to want a system that is great sounding in conventional terms. The point of my comment is that in the room you've got, not so much.

You wouldn't be the first guy to buy a house or better yet had one custom built, so he could set up the listening room of his dreams. I don't know how dedicated you are to good sound, but until you've gone that far, you are looking up at some people that you may look down on.

Quote
If your dream is building an anechoic chamber, I don't want to get in the way of your dreams, but most find anechoic chambers a lot weird sounding.

Quote

Who said anything about wanting an anechoic chamber??? This is the second time you have made really strange statements here.



There is another point here. Whether you realize it or not, you are further down the road than you might perceive to building that anechoic chamber that you say you don't want.

Quote
Perhaps you aren't the best person to be giving advice on the topic of acoustics.


Never said I was. Talk about strange comments! ;-)

Quote
I have 8 acoustic panels in my room. Hardly an anechoic chamber!


For the size of the room and the panels...



Quote
Trying to obtain good sound quality in such a tight space is really challenging.


Gee, well thanks for nothing.  I may as well have not asked you to reply.


You might want to try to work on fiegning civilized treatment to people who tell you what you may not want to hear when you grow up, Rich. ;-)

Acoustic treatment

Reply #47 –
First, implying that my room is an anechoic chamber is just utter nonsense. A fair amount of my walls are uncovered, and I have tile floors. If I had an anechoic chamber the majority of the wall surface area would be covered in absorption.

You're right, in this department you don't have much to offer. I'll rather talk to the experts at Gearslutz or Shack rather than talk to you.

Acoustic treatment

Reply #48 –