room treatment

Digital Viper-X-

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Working on my HT / Music room, it's 16 x 10, with laminate flooring, and drywall, also exposed ceiling for now while I finish it slowly.

I've heard about room treatment but don't have a clue to start. I'm using 2 Paradigm Monitor 7 towers, never really use the sub-woofer for movies, but I might start at some point.

Only thing I've seen are bass traps, what else should I be looking into?
 
Not saying that room treatments are bad, but, you might be spending a lot of money to achieve very little.

If you want to spend money buy two subs. Proper placement of these will sort out most bass problems. Then put down some carpet, rugs, nice curtains etc and you should have a pretty good room. Most home cinema rooms that I have been that have had room treatments sound lifeless.

Good speaker placement and some curtains and carpet are all the room treatment most home cinema rooms need.
 
Aah how dare you remind me about two subs! I have two but one has a busted amp and I haven't been able to replace it for over a year!! Too much damn money. It costs as much as I paid for the damn sub. So I have been trolling for the same model but gooood luck. It is a now defunct company.

Two subs is a good idea. If you have that, good speaker placement and proper eq adjustment, a room treatment is usually not needed.

Room treatments are generally used in order to get that last 5% out of a system or bc the room itself has serious issues with reflection aka echo or freq boosts or dips.

Google room frequency response for more info on fine tuning your room. Caution: this goes into the deep end of the audio pool.

So go ahead and set it up as is and go from there. First is proper setup, then consider a 2nd sub and then room treatment only if something about the sound bugs you.
 
Well, it depends.
Placement options are usually limited, unless you can afford a dedicated room.
Some room issues cannot be solved by EQ (e.g. cancellations); also EQ affects phase.

At the same time, looking at the price of some room treatments I can only say WTF. DIY seems to be the way to go.
 
Working on my HT / Music room, it's 16 x 10, with laminate flooring, and drywall, also exposed ceiling for now while I finish it slowly.

I've heard about room treatment but don't have a clue to start. I'm using 2 Paradigm Monitor 7 towers, never really use the sub-woofer for movies, but I might start at some point.

Only thing I've seen are bass traps, what else should I be looking into?

Set it up and listen to it before thinking about treatments. Setting up treatments properly can vary from being easy to needing a physics degree.
 
It is currently setup, I'm find the bass just feels off. (I usually don't even use 1 subwoofer :p ) I Find the bass from the fronts to be sufficient for 99% of my use.

Another reason for wanting to "treat' the room is to prevent so much sound from going upstairs, but that has more to do with finishing the ceiling.
 
reflective surfaces generally aren't good. Try to lay down some thick carpet or rugs, minimize mirrors/glass etc. One thing I've found good is sticking up some canvas art/prints. Behind which you can put up some eggshell foam. Doesn't look like room treatment but behaves like it. Also make sure your speakers are properly damped, braced, stuffed.
 
Your best starting point is adjusting speaker positions and running corrective room EQ if you have one (YPAO, MCACC, Audyssey). Bass and low bass are not really easy to treat a room for, as the wavelengths are long and tend to pass through most surfaces. Something like laminate flooring will not change the characteristics of those frequencies.

If room EQ doesn't fix the issue, multiple subs should (if positioned properly with regards to frequency wavelength vs distance from walls).
 
Not saying that room treatments are bad, but, you might be spending a lot of money to achieve very little.

If you want to spend money buy two subs. Proper placement of these will sort out most bass problems. Then put down some carpet, rugs, nice curtains etc and you should have a pretty good room. Most home cinema rooms that I have been that have had room treatments sound lifeless.

Good speaker placement and some curtains and carpet are all the room treatment most home cinema rooms need.

such nonsense.
 
Low frequencies require quite a bit of density to block or reshape. Adding another subwoofer and throwing some carpet or curtain up on surfaces, goes against the physics of sound if you're intending to calibrate audio for accuracy. The additional subwoofer causes more standing waves. Standing waves not only cause "booming" bass, it also causes a physical shift in frequency because the lower frequencies displace more air particles, disallowing for proper travel of a wideband frequency range. Without an open auditorium or field, the low frequency waves travel and cancel each other out as they bounce around in your environment. Bass traps are more important than anything, next comes room mode adjustments and early reflection point nulling. Everything past early reflection points can be ignored unless you have an enclosed space that limits the sound depth from playback origin. At 16x10, it's fine for average SPL listening levels. Throwing acoustic foam on the walls beyond the early reflection points over-deadens the room and is only good for a vocal booth, not a playback room. If you have drums, mid-weight bass traps spread across the room make sense -- but only in a recording environment, not playback. Adding the additional bass trapping to the walls (beyond corners and ceiling) creates a dry studio. The whole amateur idea of clapping in the center of the room, and isolating until you don't hear echo is a very bad way to calibrate a room, as the dominant frequency you're dampening sits at 300-600Hz, and carries a lot of your stereo image (delay.) Measurement microphones are inexpensive, as are ruler-flat interfaces -- you could even buy/return at banjo depot. Ideally what you want to do about room mode is set the microphone up at your listening position, and playback the same audio/record it then adjust the equalizer until the two sound waves null or come as close to that mark as possible.

tl;dr bass traps in your corners and suspended above the source and/or listening position depending on room mode and ceiling height/angle (comb filter comes into play based on height), pillows or mid-density foam at your early reflection points (can be found with a mirror, and another person, or an SPL meter.)
 
I think that you can make bass traps very cheaply with some rolls of insulation painted black? Old memory when I had nice speakers.
 
I think that you can make bass traps very cheaply with some rolls of insulation painted black? Old memory when I had nice speakers.

Owens Corning 703/705 stacked, burlap and whatever wood or metal frames makes for cheap bass traps.

Even a chick can do it ;)

Stay away from that Pink Panther roll shit, even a couch would work better.
 
Thanks for the info guys :) lots of useful stuff, I might start with building my own like in the link there, How many of those do I really need? one on the back wall?
 
Thanks for the info guys :) lots of useful stuff, I might start with building my own like in the link there, How many of those do I really need? one on the back wall?

It depends on your room and nulls. Bass traps need to be placed where the sound wave and room don't get along. You'll need to measure this from your listening position(s).
 
how does one measure this :p>

Omnimic or REW.

http://www.hometheatershack.com/roomeq/
http://www.daytonaudio.com/index.php/omnimic-v2-precision-measurement-system.html



Please note, this is going to take some patience if you really want to do it right*. You may also find that just doing a sub crawl or running a room EQ (if your receiver has one) does the trick. I'd start with that, since neither are likely to cost you any money right off the bat.

*There is no 100% guarantee.You may need some sort of DSP, or multiple subs. With a single sub, there will almost always be nulls in your frequency response, but proper placement can move the null away from your listening position.
 
Omnimic or REW.

http://www.hometheatershack.com/roomeq/
http://www.daytonaudio.com/index.php/omnimic-v2-precision-measurement-system.html



Please note, this is going to take some patience if you really want to do it right*. You may also find that just doing a sub crawl or running a room EQ (if your receiver has one) does the trick. I'd start with that, since neither are likely to cost you any money right off the bat.

*There is no 100% guarantee.You may need some sort of DSP, or multiple subs. With a single sub, there will almost always be nulls in your frequency response, but proper placement can move the null away from your listening position.

I have already run Audyssey on 3 listening positions, should I do all 6 even though there are only currently 3 seats?
 
I have already run Audyssey on 3 listening positions, should I do all 6 even though there are only currently 3 seats?

Which version of Audyssey do you have? XT and XT32 are the only ones that will EQ a sub based on room modes. What settings did Audyssey apply?
 
Yep, that will not correct the issue you're having.

How much time, effort and/or money are you willing to invest in getting it right? :p Can you play some sine waves to see what frequencies you're having an issue with? I'd start at about 200hz and work down to 30hz to see where your dip is.
 
I still say that you should spend more time setting up the speakers and sub in good locations. Using REW is a good idea. The less you EQ you have to use the better.

And going back to what I said earlier, two small subs will be better than one big sub in most rooms.

Since you are using audyssey you might find this link usefull

http://forum.blu-ray.com/showthread.php?t=159948

But saying all that, the speakers you have are very lacking in the bass area. They only go down to 55hz. Get at least one sub and set the crossover to around 60hz.

Or have I read it wrong and you have a sub? It isn't mentioned in your posts.
 
Yep, that will not correct the issue you're having.

How much time, effort and/or money are you willing to invest in getting it right? :p Can you play some sine waves to see what frequencies you're having an issue with? I'd start at about 200hz and work down to 30hz to see where your dip is.

I'm willing to spend time :) money is another story all together, and it depends, I'm not ready to drop $1500 into something that might give me "slightly" better.

But DIY like the video posted I have no problem trying, might make 2 and start there.

I'll try the sine waves tonight.


I still say that you should spend more time setting up the speakers and sub in good locations. Using REW is a good idea. The less you EQ you have to use the better.

And going back to what I said earlier, two small subs will be better than one big sub in most rooms.

Since you are using audyssey you might find this link usefull

http://forum.blu-ray.com/showthread.php?t=159948

But saying all that, the speakers you have are very lacking in the bass area. They only go down to 55hz. Get at least one sub and set the crossover to around 60hz.

Or have I read it wrong and you have a sub? It isn't mentioned in your posts.

I have Monitor 7 V.4
Design 2-driver, 2 1/2-way bass reflex,
Quasi-3rd order resistive port

Crossover 3rd order electro/acoustic at 2.0kHz
2nd-order electro/acoustic at 400 Hz

High-Frequency Driver 25mm (1") PTD

Bass/Midrange Driver 165mm (6 1/2") ICP cone,
die-cast chassis

Bass Driver 165mm (6 1/2") carbon- infused cone die-cast chassis

Low Frequency Extension 33Hz (DIN)

Frequency Response On Axis-0 degrees +/-2db from 47Hz-20kHz
Off Axis-30degrees +/-2db from 47Hz-18kH

Sensitivity Room/Anechoic 93dB/90dB

Suitable Amplifier Power Range 15-175 watts

Maximum Input Power 120 watts

Impedance Compatible with 8 ohms

Internal Volume 45 L/1.60 cu ft

I prefer *NOT* to use the sub in most cases, specially for music, I find it too overwhelming, even with the Audyssey EQ.

:)

Currently I have a 10" sub, but I also picked up a 12" Sony that I will be trying soon.
 
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For most music, you don't want anything other than two speakers. So you have that right.

My receiver has a "pure audio" button that essentially is an upsampling dac that also changes the output from 5.1 to stereo with no sub for music. So when I game I leave it off but when I want to listen to music, even with headphones, I hit that button and go pure stereo.
 
Wow, the guide to Audyssey is huge, I made a few critical mistakes in my setup, I will re-do it tonight when my son is sleeping. ( also the understanding bass was useful )
 
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I have Monitor 7 V.4


I prefer *NOT* to use the sub in most cases, specially for music, I find it too overwhelming, even with the Audyssey EQ.

:)

Currently I have a 10" sub, but I also picked up a 12" Sony that I will be trying soon.

Yeah, those are the speakers I was talking about, they are rated down to 47hz but most seem to drop off at around 55hz. They are nice speakers but most reviews say that they need a sub to work best.

There might be something wrong with your sub setup if you are finding it too overwhelming. It shouldn't be like that at all. I agree for most music, stereo is way better but for some types it's really nice to have the extra depth a sub adds.

You are picking up a 12 inch sub? So that means you will have two subs? :) You will be able to see for yourself then if two is better than one!!

Wow, the guide to Audyssey is huge, I made a few critical mistakes in my setup, I will re-do it tonight when my son is sleeping. ( also the understanding bass was useful )

Yeah I found that guide very useful myself. As you can see there is a lot you can do to get your bass just right without spending any money. Hope it helps you get your bass just right :) Let us know how you get on.
 
Yeah, those are the speakers I was talking about, they are rated down to 47hz but most seem to drop off at around 55hz. They are nice speakers but most reviews say that they need a sub to work best.

There might be something wrong with your sub setup if you are finding it too overwhelming. It shouldn't be like that at all. I agree for most music, stereo is way better but for some types it's really nice to have the extra depth a sub adds.

You are picking up a 12 inch sub? So that means you will have two subs? :) You will be able to see for yourself then if two is better than one!!



Yeah I found that guide very useful myself. As you can see there is a lot you can do to get your bass just right without spending any money. Hope it helps you get your bass just right :) Let us know how you get on.

I have 2 :p Selling one!!! haha,

I didn't get a chance to re-tune it last nite, maybe tonight!
 
For most music, you don't want anything other than two speakers. So you have that right.

My receiver has a "pure audio" button that essentially is an upsampling dac that also changes the output from 5.1 to stereo with no sub for music. So when I game I leave it off but when I want to listen to music, even with headphones, I hit that button and go pure stereo.

You want to use the sub with music. Unless you have some pretty obscenely big n' powerful speakers, like Dunaly SC-Vs or something, your speakers don't do low bass that well. It isn't just about how low they can go, but what their distortion is at those low levels and how it effects the higher frequency sounds.

Basically think of the subwoofer as just another driver on the speakers. It turns 2.5 way speakers in to 3.5 way or 3 way in to 4 way and so on. Best idea is to let it do what it does best. It'll give you better bass and cleaner mid-bass.

Now this is all predicated on having a well setup system, of course, that handles the handoff well. Something like Audyssey calibration is real useful in that regard. However when you have a good setup, music is better with the sub than without.
 
Having not had a sub in mys system for a while... Wouldn't using a sub ruin imaging for the bass?
 
Having not had a sub in mys system for a while... Wouldn't using a sub ruin imaging for the bass?

Not even a tiny bit, unless it's a crappy sub. 80hz and down is non localized unless the sub has significant ringing or distortion. The vast vast majority of floorstanding mains will not play full range, regardless of advertising or spec sheets. Most of them will be giving out quite a bit of harmonic distortion below a certain frequency (often around 50-60hz) unless they are really well built.
 
You want to use the sub with music. Unless you have some pretty obscenely big n' powerful speakers, like Dunaly SC-Vs or something, your speakers don't do low bass that well. It isn't just about how low they can go, but what their distortion is at those low levels and how it effects the higher frequency sounds.

Basically think of the subwoofer as just another driver on the speakers. It turns 2.5 way speakers in to 3.5 way or 3 way in to 4 way and so on. Best idea is to let it do what it does best. It'll give you better bass and cleaner mid-bass.

Now this is all predicated on having a well setup system, of course, that handles the handoff well. Something like Audyssey calibration is real useful in that regard. However when you have a good setup, music is better with the sub than without.

I use it for headphones. I used to use it when I had some AV123 550 MKII towers.

Now I go from 5.1 speakers to headphones when I hear, "turn that down!" from the wife lol.
 
ok,, moved the couch away from the back wall about 2 feet, moved the sub 2 feet away from the wall as well, set all speakers to small, re-did the audyssy test with all 6 positions correctly placing the mic, it sounds Much more balanced now,


not sure that i like the the sub in music still, i find it just doesn't blend in very well with the music, its not overwhelming like before, but it does seem to stick out when it works, should i reduce the cross-over to below 80 hz? its set at 80 at moment, audyssy set the fronts to large, with no cross-over, after reading that guide though i set them to small and set the subwoofer for lfe + main with the crossover for the fronts at 60hz.
 
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ok,, moved the couch away from the back wall about 2 feet, moved the sub 2 feet away from the wall as well, set all speakers to small, re-did the audyssy test with all 6 positions correctly placing the mic, it sounds Much more balanced now,


not sure that i like the the sub in music still, i find it just doesn't blend in very well with the music, its not overwhelming like before, but it does seem to stick out when it works, should i reduce the cross-over to below 80 hz? its set at 80 at moment, audyssy set the fronts to large, with no cross-over, after reading that guide though i set them to small and set the subwoofer for lfe + main with the crossover for the fronts at 60hz.

It depends what the cutoff is on your tops. You generally do not want a gap between your tops and subs. Neither would you want your tops overlapping your sub cutoff visa versa.

For music, it should be in stereo , no crossover cutoff ( full range) with no sub. Not sure what pre amp you're using , but if you have a direct mode use it or use the audyssey eq to your liking with no crossover cutoff and sub. This is assuming your fronts are full range towers
 
I solved the wife ack by building a listening room to a separate building :)

When room treating, the easyest and worst mistake is to dampen the room with soft materials too much. Traditional 'acoustics' materials do little to nothing to lower frequencies and result in a snuffed up sound. Bass traps then again usually have to be tuned for specific frequencies, using them requires some knowledge and measurements.

Easy and relatively painless way to improve room acoustics is to place a couple of acoustics boards to the closest walls next to the speaker. You can place a mirror on the wall to see from which point early reflections from the speaker will be coming - that's where you'll want to place your acoustics pads.
 
lol says you. And pretty much everything in my post is pretty spot on.

absolutely not.

you said:

"Then put down some carpet, rugs, nice curtains etc and you should have a pretty good room. Most home cinema rooms that I have been that have had room treatments sound lifeless. "

first of all, carpet, rugs, curtains, etc are thin porous absorbers and are not sufficient to attenuate a full, broadband indirect specular signal.

in small residential rooms, the lower schroeder (davis) cut-off is typically around 250-300hz (where wavelength is small with respect to boundary size and thus behaves specularly). thus, a porous absorber used to attenuate an indirect signal must be sufficiently thick (and large) to be effective to this lower cut-off. thin porous absorbers like what you stated will simply filter (eq/color) the reflection as the mid-HF band is attenuated but the lower specular band persists.

it is true that many rooms with "room treatment" sound lifeless - this is a result of operator error, where the user simply does not understand the fundamentals.

you'll also see over-application of thin porous absorbers which do make the room lifeless as they overattenuate the mid-HF band but do not address lower band (or modal region) issues appropriately.

for home theaters, it is best to use a LF absorber + mid-HF diffuser such as a Binary Amplitude Grating (BAD) diffuser - which offers spatial dispersion (but no temporal dispersion). there is generally not enough real estate for good broadband Reflection Phase Gratings (QRD/PRD) due to minimum distance limitations - but they are good applications for 2ch stereo.
 
Low frequencies require quite a bit of density



The additional subwoofer causes more standing waves. Standing waves not only cause "booming" bass, it also causes a physical shift in frequency because the lower frequencies displace more air particles, disallowing for proper travel of a wideband frequency range.

absolutely incorrect. additional subwoofers do not "cause more standing waves". the room dictates resonances; the subwoofers merely drive these resonances.

the "booming" is not a function of just the frequency response but also the decay times of the LF energy. in a resonance, the energy tends to persist. LF decay times must be controlled.


Without an open auditorium or field, the low frequency waves travel and cancel each other out as they bounce around in your environment.

what you're attempting to describe is spatial polar lobing


Bass traps are more important than anything, next comes room mode adjustments and early reflection point nulling.

what on earth is "early reflection point nulling"?


Throwing acoustic foam on the walls beyond the early reflection points over-deadens the room and is only good for a vocal booth, not a playback room.

what.


If you have drums, mid-weight bass traps spread across the room make sense -- but only in a recording environment, not playback. Adding the additional bass trapping to the walls (beyond corners and ceiling) creates a dry studio.

another case of operator error.

The whole amateur idea of clapping in the center of the room, and isolating until you don't hear echo is a very bad way to calibrate a room, as the dominant frequency you're dampening sits at 300-600Hz, and carries a lot of your stereo image (delay.)

clapping is not incorrect because of the spectral content of the clap, but because source-receiver positions are different than would be for the reproduction setup. small spaces deal with local areas of variable pressure. when you "clap" the source and receiver are in (approx) same positions. this is the error.

Ideally what you want to do about room mode is set the microphone up at your listening position, and playback the same audio/record it then adjust the equalizer until the two sound waves null or come as close to that mark as possible.

what.

tl;dr bass traps in your corners and suspended above the source and/or listening position depending on room mode and ceiling height/angle (comb filter comes into play based on height), pillows or mid-density foam at your early reflection points (can be found with a mirror, and another person, or an SPL meter.)

pillows or mid-density foam is incorrect application of treatment as they are not sufficient to fully attenuate broadband indirect specular reflections.

and the mirror was only used many decades ago to illustrate the reflection behavior of specular energy (where wavelength is small with respect to boundary size) - angle of incidence = angle of reflection. the mirror details you nothing with respect to the arrival time, gain, and vector (direction) of the actual indirect energies. time-domain analysis is the right tool for the job here (via the envelope time curve)
 
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Owens Corning 703/705 stacked, burlap and whatever wood or metal frames makes for cheap bass traps.

oc703/oc705 has too high gas flow resistivity to be very effective for LF porous absorption.


Stay away from that Pink Panther roll shit, even a couch would work better.

clueless.
porous absorbers "work" by converting the kinetic energy of particle velocity of the soundwave into heat via friction against the porous structure. thus, the porous insulation needs to be placed into areas of high particle velocity in order to be effective. particle velocity and pressure are inversely proportional. as pressure maximizes at the boundary, particle velocity goes to zero. thus, thin porous absorbers are not effective at lower frequencies. as one constructs thicker and thicker porous absorbers (to place the porous structure into areas of higher particle velocity for the lower/longer wavelengths), one needs to use a material with lower gas-flow-resistivity. complex acoustical impedance is at play, so one cannot merely look at the real/resistive component - you must also factor in the complex imaginary component. any change in acoustical impedance (with respect to air) is going to result in a reflection. materials with low gas flow resistivity will be far more effective at LF absorption (eg, thick traps of pinnk fluffy attic insulation).

it is common misconception in acoustics that denser (higher GFR) material is more effective for LF absorption.

may i recommend:
http://soundflow.afmg.eu/index.php/sf-features-en.html
http://www.amazon.com/Acoustic-Absorbers-Diffusers-Theory-Application/dp/0415471745
http://www.whealy.com/acoustics/Porous.html
 
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