danadam
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If those rooms looked like in those pictures then I'd like a third sample from a room with typical/normal furniture.
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Room Treatments in the Real World
- Thread starter FrantzM
- Start date
- Thread Starter
- #22
Reviving this thread ... Room is being painted. It is much smaller than I anticipated a year ago ...
4.8 x 3.2 x 2.6 meters ( L x W x H) ...
dual purpose room, concrete all over with glass windows that will be covered with thick drapes.
I don't believe in dealing with bass issues with room treatments. I have 3 subs, could be overkill for such a small room , I will try to use 2. Room is mine, other people can use it but its main purpose is music and HT. Man-cave. Mine
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What does the collective suggest? I would later try to limit transmission and noise from the other rooms... For now, I will try these, Amazon TroyStudio Acoustic Studio Absorption Foam Panel - Broadband Sound Absorber - Periodic Groove Structure - 12'' X 12'' X 2'', PACK of 6 @ $12.99, these are cheap enough to try but ....
there has to be a better way to know what to use? I am sure I am not alone in this ..
4.8 x 3.2 x 2.6 meters ( L x W x H) ...
I don't believe in dealing with bass issues with room treatments. I have 3 subs, could be overkill for such a small room , I will try to use 2. Room is mine, other people can use it but its main purpose is music and HT. Man-cave. Mine
.What does the collective suggest? I would later try to limit transmission and noise from the other rooms... For now, I will try these, Amazon TroyStudio Acoustic Studio Absorption Foam Panel - Broadband Sound Absorber - Periodic Groove Structure - 12'' X 12'' X 2'', PACK of 6 @ $12.99, these are cheap enough to try but ....
there has to be a better way to know what to use? I am sure I am not alone in this ..
ernestcarl
Major Contributor
Two inches is really too thin for acoustic foam panels to be all that effective. Maybe better to layer two panels together with a flat panel underneath to make it 3-4 inches thick.
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The best way to use 2"-thick foam squares is to glue them onto panels of 1/2" or 1/4" plywood, of different sizes, maybe 4' x 2', 6' x 4', and so on. Then suspend the panels from their top edges, several inches off the wall.
Foam arrays are velocity absorbers, and to put them directly on the wall is to put them where velocity approaches zero, diminishing their effectiveness. An air gap behind helps a lot. Plus the suspended panels themselves act as lossy membranes against lower frequencies. Win-win.
Because I think bass issues should be dealt with by room treatment, if possible. DSP can bring down standing waves so that a REW curve looks better, but remember that a standing wave is not an amplification of your speaker's signal. It's a pure fundamental, harmonically dumb, no better than the hoot you get blowing across an empty beer bottle. You might be able to get that sound leveled off in terms of amplitude, but it's not a sound you want to hear.
Foam arrays are velocity absorbers, and to put them directly on the wall is to put them where velocity approaches zero, diminishing their effectiveness. An air gap behind helps a lot. Plus the suspended panels themselves act as lossy membranes against lower frequencies. Win-win.
Because I think bass issues should be dealt with by room treatment, if possible. DSP can bring down standing waves so that a REW curve looks better, but remember that a standing wave is not an amplification of your speaker's signal. It's a pure fundamental, harmonically dumb, no better than the hoot you get blowing across an empty beer bottle. You might be able to get that sound leveled off in terms of amplitude, but it's not a sound you want to hear.
Hipper
Addicted to Fun and Learning
Frantz, are you going to be doing any measuring?
You can measure in a number of ways, from the simplest and least accurate to the most accurate but much more complicated:
1. Simply your ears.
2. Using a set of test tones and your ears.
3. Test tones and a sound pressure level meter.
4. Sophisticated software (such as Room EQ Wizard - REW) plus laptop, microphone etc..
Test tones and your ears is a good starting point. A useful set of bass test tones can be got free here:
http://realtraps.com/test-cd.htm
(there's lots of useful advice on this site)
I would start by trying to find the optimal speaker and listening chair positions, optimal for listening that is. Try different positions and measure for bass reproduction only, say 0-500Hz. It won't be the best sound but it will be better then just placing the speakers so they look neat or are practical for the room use. I use 'The Thirds' as described here:
http://www.barrydiamentaudio.com/monitoring.htm
I suggest you use this as a starting point. Then measure, move the speakers; measure again etc. etc..
The principle is to get the bass as best as you can before looking at the higher frequencies.
Once you've done this, you can look at subwoofers and their positioning, room treatment and DSP/EQ, or a combination of any or all these.
By the way, I'm not a lover of foam. I tried Auralex foam in my first attempts but I later found that products by GIK were far superior in effect. Here's an interesting article about the shape of foam:
https://soundblackout.com/sound-proof-foam-panels-pyramid-acoustic-foam-vs-wedge/
You can measure in a number of ways, from the simplest and least accurate to the most accurate but much more complicated:
1. Simply your ears.
2. Using a set of test tones and your ears.
3. Test tones and a sound pressure level meter.
4. Sophisticated software (such as Room EQ Wizard - REW) plus laptop, microphone etc..
Test tones and your ears is a good starting point. A useful set of bass test tones can be got free here:
http://realtraps.com/test-cd.htm
(there's lots of useful advice on this site)
I would start by trying to find the optimal speaker and listening chair positions, optimal for listening that is. Try different positions and measure for bass reproduction only, say 0-500Hz. It won't be the best sound but it will be better then just placing the speakers so they look neat or are practical for the room use. I use 'The Thirds' as described here:
http://www.barrydiamentaudio.com/monitoring.htm
I suggest you use this as a starting point. Then measure, move the speakers; measure again etc. etc..
The principle is to get the bass as best as you can before looking at the higher frequencies.
Once you've done this, you can look at subwoofers and their positioning, room treatment and DSP/EQ, or a combination of any or all these.
By the way, I'm not a lover of foam. I tried Auralex foam in my first attempts but I later found that products by GIK were far superior in effect. Here's an interesting article about the shape of foam:
https://soundblackout.com/sound-proof-foam-panels-pyramid-acoustic-foam-vs-wedge/
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bo_knows
Addicted to Fun and Learning
I agree with you 100%. This is the first time I heard room treatments being called snake oil!? LOL. Revel's owner's manual for the Ultima series mentions acoustic treatments and it shows their locations.
"As previously mentioned, the Salon2/Studio2 Loudspeakers utilize high-order networks which optimize both the on-axis and off-axis response. Their optimized response minimizes sonic degradation that can occur in overly “live” rooms. Placing minimal acoustic treatment materials at primary reflection points will reduce these distortions even further. Ideally, acoustic absorbers should be placed at the first reflection points on the front and side walls and either acoustic absorbers or diffusers should be placed at the first reflection points on the rear wall. ".
- Thread Starter
- #27
WoW!
Thanks People!. Few things:
I know and have experienced non-linear bass reproduction in many rooms. In my experience this is best dealt with multiple low frequency radiators aka subwoofers. I am OK with it and am using in my current HT. I linearize as best s I can the subs with a miniDSP and the integration with the HT is brought in by the Audyssey XT32 app, I am satisfied in the bass for now...
In my current living room, there are large windows that open on the outside (natural ventilation), furniture and drapes and the room opens on another large room/dining room with opened very large windows for natural ventilation. I live in a tropical country and AC is not available at all times. The room has no echo I can perceive and well it sounds good... For movies it is most satisfying , for music? .... meh..
he room I am moving into, my man-cave will not have that. It is enclosed. The room being small and insulated, I can use a low power split air conditioner that can run from my solar off-grid electrical system. Right now the room is empty and there is clearly echoes when I am conversing, even on the phone.
I will use some absorption at the first reflection point areas and likely quite a bit in the back... My question remains:
What am I trying to achieve objectively?
Are there threshold I am trying to reach? Attain? For example: Reverberation Time? At what frequencies?
What frequencies should I diffract? absorb?
How? What material?
I understand it is somewhat empirical but at this point in time I am flying blind from say150 Hz and up.
Thanks People!. Few things:
I know and have experienced non-linear bass reproduction in many rooms. In my experience this is best dealt with multiple low frequency radiators aka subwoofers. I am OK with it and am using in my current HT. I linearize as best s I can the subs with a miniDSP and the integration with the HT is brought in by the Audyssey XT32 app, I am satisfied in the bass for now...
In my current living room, there are large windows that open on the outside (natural ventilation), furniture and drapes and the room opens on another large room/dining room with opened very large windows for natural ventilation. I live in a tropical country and AC is not available at all times. The room has no echo I can perceive and well it sounds good... For movies it is most satisfying , for music? .... meh..
he room I am moving into, my man-cave will not have that. It is enclosed. The room being small and insulated, I can use a low power split air conditioner that can run from my solar off-grid electrical system. Right now the room is empty and there is clearly echoes when I am conversing, even on the phone.
I will use some absorption at the first reflection point areas and likely quite a bit in the back... My question remains:
What am I trying to achieve objectively?
Are there threshold I am trying to reach? Attain? For example: Reverberation Time? At what frequencies?
What frequencies should I diffract? absorb?
How? What material?
I understand it is somewhat empirical but at this point in time I am flying blind from say150 Hz and up
.
ernestcarl
Major Contributor
I am no expert, but here's some of my thoughts:
What am I trying to achieve objectively?
Absorbing early reflections means you get less time smearing which will improve clarity.
Scattering will help spread reflections more randomly and increase envelopment without the room sounding too dead -- although MCH mixing can help with envelopment as well.
Perhaps much better if some interchannel decorrelation (edit: rather the correct term here is binaural dissimilarity) were achieved in your treatments rather than having everything completely symmetrical.
Are there threshold I am trying to reach? Attain? For example:
Reverberation Time? At what frequencies?
Whatever you do, RT should at least be more even/flat across the entire frequency range.
What frequencies should I diffract? absorb?
Everything around and above Schroeder seems reasonable and doable. Treating the lower bass is much more involved -- needs lots of treatment material.
How? What material?
I understand it is somewhat empirical but at this point in time I am flying blind from say150 Hz and up.
Take detailed measurements prior to treatment; you will then have a clear baseline that you will keep as your master reference. Let's say 6 or 9 multiple, full-range 90 degree (calibrated mic) sweeps from each channel at the LP. Save every last one of these, & vector average them later to get more stable time domain information as well -- avg of left, right, and both.
What am I trying to achieve objectively?
Absorbing early reflections means you get less time smearing which will improve clarity.
Scattering will help spread reflections more randomly and increase envelopment without the room sounding too dead -- although MCH mixing can help with envelopment as well.
Perhaps much better if some interchannel decorrelation (edit: rather the correct term here is binaural dissimilarity) were achieved in your treatments rather than having everything completely symmetrical.
Are there threshold I am trying to reach? Attain? For example:
Reverberation Time? At what frequencies?
Whatever you do, RT should at least be more even/flat across the entire frequency range.
What frequencies should I diffract? absorb?
Everything around and above Schroeder seems reasonable and doable. Treating the lower bass is much more involved -- needs lots of treatment material.
How? What material?
I understand it is somewhat empirical but at this point in time I am flying blind from say150 Hz and up
.Take detailed measurements prior to treatment; you will then have a clear baseline that you will keep as your master reference. Let's say 6 or 9 multiple, full-range 90 degree (calibrated mic) sweeps from each channel at the LP. Save every last one of these, & vector average them later to get more stable time domain information as well -- avg of left, right, and both.
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I posted my GIK treated room in The room treatment thread here, very happy with the sound and quality/finish of the panels, not that expensive either, certainly better value than a £2000 cable.
Hipper
Addicted to Fun and Learning
What am I trying to achieve objectively?
Smooth relatively flat on axis response at your listening position through the whole spectrum - 0-20kHz. Decay times consistent through the spectrum (mine are around 200ms but most would probably find that too low). Some talk about phase as another issue but I found that if you correct frequency response phase seems to follow so I didn't worry about it.
Many people just don't do flat but use a 'house curve'. Often that is a slope ranging anything from 3db to 6db up at the bass end of the spectrum down to the treble. I'm happy with flat and add a bit to the treble to deal with my deteriorating old ears.
Don't get obsessed with smooth or flat graphs. Make them reasonably so if you can. Look at them as a tool to try and reach your real goal, being able to listen to your music in your room so that it sounds good to you, which is of course subjective!
What frequencies should I diffract? absorb?
As I understand it diffraction is the bending of waves. As far as I know we don't use that in acoustic treatment. Diffusion is the scattering of waves in many directions and we do use diffusors. Here's a piece by Ethan Winer of Real Traps about diffusion:
My experience in a room not much bigger then yours (4.2m x 3.86m) is that it is too small to use them. They seem to need a distance from the listening position for them to do their job and not be heard. I found I could hear them so I don't use diffusors, just absorbers. Therefore if considering diffusors look into the distances they can work at.
They key objective in all this, as I may have mentioned before, is to get the bass right - say 0-500Hz. The rest will sound pretty good once that's done. Of course you can improve the higher frequencies too. Often this can be done by reducing reflections but particularly for those from the side walls, some people like them. I don't and place panels on the outside of each speaker to reduce them. I find it makes the overall sound clearer, sharper. You can of course experiment with this.
Smooth relatively flat on axis response at your listening position through the whole spectrum - 0-20kHz. Decay times consistent through the spectrum (mine are around 200ms but most would probably find that too low). Some talk about phase as another issue but I found that if you correct frequency response phase seems to follow so I didn't worry about it.
Many people just don't do flat but use a 'house curve'. Often that is a slope ranging anything from 3db to 6db up at the bass end of the spectrum down to the treble. I'm happy with flat and add a bit to the treble to deal with my deteriorating old ears.
Don't get obsessed with smooth or flat graphs. Make them reasonably so if you can. Look at them as a tool to try and reach your real goal, being able to listen to your music in your room so that it sounds good to you, which is of course subjective!
What frequencies should I diffract? absorb?
As I understand it diffraction is the bending of waves. As far as I know we don't use that in acoustic treatment. Diffusion is the scattering of waves in many directions and we do use diffusors. Here's a piece by Ethan Winer of Real Traps about diffusion:
My experience in a room not much bigger then yours (4.2m x 3.86m) is that it is too small to use them. They seem to need a distance from the listening position for them to do their job and not be heard. I found I could hear them so I don't use diffusors, just absorbers. Therefore if considering diffusors look into the distances they can work at.
They key objective in all this, as I may have mentioned before, is to get the bass right - say 0-500Hz. The rest will sound pretty good once that's done. Of course you can improve the higher frequencies too. Often this can be done by reducing reflections but particularly for those from the side walls, some people like them. I don't and place panels on the outside of each speaker to reduce them. I find it makes the overall sound clearer, sharper. You can of course experiment with this.
dasdoing
Major Contributor
audiophiles tend to ignore the time domain.
ringing in the bass is realy realy annoying once you heard a treated room.
I sugest going into a bathroom and hum in diferent frequencies until you find the modes. then sing some melodies with notes around a mode and you soon realize how destrutive they are. there is no way to EQ or multi-sub ringing
ringing in the bass is realy realy annoying once you heard a treated room.
I sugest going into a bathroom and hum in diferent frequencies until you find the modes. then sing some melodies with notes around a mode and you soon realize how destrutive they are. there is no way to EQ or multi-sub ringing
Unless you plan to use this room as home cinema only the best solution is to visit some hi-fi showrooms and studio control rooms for understanding your preferences. Some people prefer dry sound with low RT, some prefer something livelier with scene and reverb.
Your room is very small, that is bad, but have few windows, so maybe bass troubles will be not so horrible.
For diffusion there is one big problem - diffusers require some distance for making truly diffuse scatter pattern. If you use them closer, you'll have tonally wronr reflection.
If you need some home cinema only, there are some Dolby Labs/THX requirements, that can be resumed as "dry as hell". In fact you need to kill all reflections as spatial info is delivered from different points by multiple tracks.
Also, all these good recommendations are always restricted by budget.
Personally I'd recommend you to get any audio interface with microphone for quantitative estimating problems and efficiency of your treatment. Maybe just UMIK. I prefer to see and compare "before and after" before I'll make wrong path till the end...
Just wanted to chime in on a question I've been wondering. I use to produce music and a dead sounding room was ideal. For audiophile setups I've read that you don't want to over dampen the room. So when approaching acoustic treatment does how much you treat the room depend on your purpose? I rather liked the over dampened sound of my old studio so even though Im now only using my desktop setup for music listening, is it wrong for me to build panels and use bass traps all around to almost "over dampen" my room? Are there any objective drawbacks to having a studio like room or is purely preference?
Any "objectives" depend on goal.
If you like dry and overdamped sound and the goal is to get pleasure, i don't see any problems.
PS
Typical situation with most audiophiles is that they don't like low RT due to impossibility to make good simulation of big embracing sound and wide soundstage in small room without reflections. So, i think they prefer slightly smeared imaging and transients over flattish, surgically disassembled sound, which sounds totally artificial after typical live gig or orchestra sound. By the way, real performance rarely have layering, imaging and all that crap embedded into commercial record.
Typical conventional recommendations for hi-fi room is 0,4-0,6 sec RT. If you calculate room size in reverse according to studio recommendations, it's a really huge control room.
dasdoing
Major Contributor
I am pretty sure the main problem audiophiles have with treatment is the wive not letting lol
but dead-ish rooms sure seam to be stressfull to many (personaly I got used to it very fast).
there is an intresting new aprouch to this problem in rooms by Northward Acoustic: https://www.audiotechnology.com/tutorials/hearing-double-2
they basicly make the room dead for the speakers but live for the noises you make
but dead-ish rooms sure seam to be stressfull to many (personaly I got used to it very fast).
there is an intresting new aprouch to this problem in rooms by Northward Acoustic: https://www.audiotechnology.com/tutorials/hearing-double-2
they basicly make the room dead for the speakers but live for the noises you make
dasdoing
Major Contributor
I never understood this. you don't need reflections for this, just widen the triangle
- Thread Starter
- #37
Thanks for the reply.
I don't travel much these days. The windows will be closed and draped, For low bass I use multiple subs. I can get a pretty decent FR in my present, larger room. I expect to get great bass in room, I could use up to 3 subwoofers in a Geddes configuration (DSP is miniDSP 2 x4) the subs. I will optimize the subs the best I can, then try to see how I can have a settings for movies with the AVR and LCR optimized by Audyssey XT32 and a music with 2-channels and the subs properly integrated ...
I am not an expert but I understand that the use of passive room correction (Room Treatments) in the lows, involves large contraptions... Simple wall covering are not effective down there at <100 Hz .. Better use multiple subs and after that, DSP and EQ to smoothen the response... From 500 Hz to 20 KHz, I am in the dark and I am sure, I am not alone and I thought, I understood the issue. Right now the room is being painted and is naked and slap echoes are easily heard, conversations are not clear. The room will of course have some furniture and drapes when finished and a lrge screen on one wall. I have now a fixed Stewart Firehawk 100 inches.
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I agree but I'm also confused. I don't mind the dry over dampened sound. It just reveals more with the music. But having played in a wind ensemble and attended lots of concerts the concert halls aren't over dampened, usually they have some dampening combined with reflection panels. Is that yet another approach with a different goal to acoustic treatment? So far it seems like treating a room can go a few ways depending if you're trying to produce music, record music, hifi listening, home theater, or live performance. Since the goals are different then are there differences in how we want to acoustically treat the room for each scenario?
I've noticed that widening my two 5 inch monitors on my desk significantly increased my sound stage. I'll experiment separating them even further but they're near fields and can't move too far back out of my desk.
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