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Acoustic curtains

outrun

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Hello all,

So recently I got myself into hifi, went through a multiple sets of speakers and amps of incremental upgrades, then finally got myself into room acoustics, and after a few nights of educating myself of the subject bought a bunch of acoustic panels and applied the knowledge building bass traps and I must say that the effect is huge, as if the speakers came to to life just now.

Now as I am listening music I can notice the lower frequencies are still booming, which is not surprising since my thickest paneling is something like 30 cm + maybe 10 cm of airgap (not sure to what frequency it corresponds to), but that's expected and I have to try to solve that problem later.

My room has a large window, I was thinking that with thick enough curtains it could provide additional dampening, but I have seen most audio engineers etc. dismiss the idea, but I don't fully understand why, because I see a lot of potential basically to have entire wall covered just with a few blankets.

Anyone more experienced in this matter I'd like to hear your opinions, also if you could recommend any decent acoustic curtains it'd be cool.
 

holdingpants01

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"acoustic" curtains won't do anything to the low end, they could make the problem even more apparent as the difference between decay of bass frequencies and the rest of the spectrum will be bigger (by dampening the mids and highs and not changing the low end). If possible make some measurements and post them here
 
OP
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outrun

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they could make the problem even more apparent as the difference between decay of bass frequencies and the rest of the spectrum will be bigger

Yep, that was my mental image as well. I am planning to tackle the low end separately, or do you think it would be too much combined with he high end (curtains)?


If possible make some measurements and post them here

Unfortunately I have nothing yet, I'm planning building Hifiberry with mic to have everything properly measured. I am learning by doing as I go through all this. Thanks for the reply.
 

holdingpants01

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Yep, that was my mental image as well. I am planning to tackle the low end separately, or do you think it would be too much combined with he high end (curtains)?

Without measurements there's no way to tell, but you can always remove them if they're too much. In my room I started with bass traps and after finished those, the carpet and a few panels at ceiling shortened the decay to 200ms, it's very easy to go too far with absorbing high frequencies
 
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NTK

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Welcome to ASR!

Dr Toole also uses heavy drapes to treat his room (source), both for the left side wall and the rear wall.
toole.png


[Edit]
To fix low frequency problems, try multi-subs with EQ.
 

DVDdoug

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or do you think it would be too much combined with he high end (curtains)?
You can improvise/experiment with a blanket, or something.

I wouldn't expect THAT much difference between a regular-thick curtain and an "high-end acoustic curtains". Except, MAYBE they publish absorption specs for the acoustic curtains.

I'm planning building Hifiberry with mic
You need a calibrated measurement mic (around $100 USD) and most people use REW software (free for personal use).

It's probably worthwhile to measure before randomly spending money on acoustic treatment. "Diagnosis before treatment". And with acoustic treatment, A/B listening tests are "difficult" and always sighted (so usually biased).
 
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outrun

outrun

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Welcome to ASR!

Dr Toole also uses heavy drapes to treat his room (source), both for the left side wall and the rear wall.

Thanks, that is interesting information, just exactly what I was looking for, no need to re-invent the wheel for myself.
 
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outrun

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This might be a really dumb question but my Yamaha HS-7 monitors had a switch for "room control" which apparently rolled back the low end when the speakers were placed against the wall (as it was in my case), so I had it on the maximum -4 dB setting to cut off of the excess bass, but now as I installed the bass traps, I noticed the low end was lacking, so I returned the switch back to default -0 dB and suddenly the low end was again balanced against the mids. Can this all be only in my head or could there be really so much difference?

I still just cannot get over how much difference there is installing 60 euros worth of some chinese foam on the walls versus paying a ton for marginally better speakers.
 

ozzy9832001

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This might be a really dumb question but my Yamaha HS-7 monitors had a switch for "room control" which apparently rolled back the low end when the speakers were placed against the wall (as it was in my case), so I had it on the maximum -4 dB setting to cut off of the excess bass, but now as I installed the bass traps, I noticed the low end was lacking, so I returned the switch back to default -0 dB and suddenly the low end was again balanced against the mids. Can this all be only in my head or could there be really so much difference?

I still just cannot get over how much difference there is installing 60 euros worth of some chinese foam on the walls versus paying a ton for marginally better speakers.
You'll get a gain boost by them being placed near a wall. So the roll off makes sense, but adding back the 4dB may actually be more than 4dB when you factor in the gain from the wall. If your MLP is near a wall, you may see even more of a boost.
 

ozzy9832001

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Hello all,

So recently I got myself into hifi, went through a multiple sets of speakers and amps of incremental upgrades, then finally got myself into room acoustics, and after a few nights of educating myself of the subject bought a bunch of acoustic panels and applied the knowledge building bass traps and I must say that the effect is huge, as if the speakers came to to life just now.

Now as I am listening music I can notice the lower frequencies are still booming, which is not surprising since my thickest paneling is something like 30 cm + maybe 10 cm of airgap (not sure to what frequency it corresponds to), but that's expected and I have to try to solve that problem later.

My room has a large window, I was thinking that with thick enough curtains it could provide additional dampening, but I have seen most audio engineers etc. dismiss the idea, but I don't fully understand why, because I see a lot of potential basically to have entire wall covered just with a few blankets.

Anyone more experienced in this matter I'd like to hear your opinions, also if you could recommend any decent acoustic curtains it'd be cool.
This is where spending the $100 on a UNIK-1 makes the most sense. Otherwise, you'll be putting panels up not really knowing if they are doing anything or not. The mind is very powerful and wanting to believe a change in happening. Proper placement of panels and traps is crucial for getting the most bang for the buck. Unless you are using membrane traps or tube traps, I'd recommend keeping porous absorbers out of the corners. They aren't very effective there because it's the pressure that builds up there...and where there is high pressure there is low or 0 velocity. If the corners are all the space you have, then I'd recommend them placed at least 1ft out from the corner.

Add limiters to the traps to prevent over absorbing the highs. That way, you can add more and maintain the decay times in the upper mid/treble.
 

Philbo King

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Heavy theatre curtains have been used for acoustic improvement in performance venues for a long time. They don't do much for low bass, but are pretty effective for damping reverb time in mids and highs. The nice thing about them is if they are mounted on a track they can be pulled back for a more lively environment.


 

kemmler3D

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In general, absorbing mids and highs is pretty easy, absorbing low frequencies is hard. As a result, if you add a lot of curtains or other absorbers, you usually end up with a boomy, boxy, or generally muffled-sounding room.

Rule of thumb: you don't want to cover more than 25% or so of the walls and ceilings' total area with non-bass absorbers, if you go beyond that it can start to sound muddy.

Your high-frequency absorption should not outpace your low-frequency absorption. I think if you add curtains, you may have that problem. I would get a mic and see what you're dealing with in the <200hz range before doing anything else.

Also, welcome to ASR! I dig the avatar... I spent several days in my youth trying to beat a rental copy of Outrun on Sega Genesis...
 

ZolaIII

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@DVDdoug actually I think there aren't much material that would do a better job than densely woven wool blanket's. Even size is similar to regular curtains and hardly there is a more healthy material for the purpose with proper upkeep of course. Tho quality ones aren't cheap nor easy to find anymore. Two waves of such would also be rather efficient because air gaps between them to help dispersion. It won't work in bass region all that much but then again little things would. Even 30 cm (around 12") thick cage with steel mesh up front has a limited effect and to the uper bass more. If possible it should be avoided putting speakers back facing the wall with glass windows and doors. If such are in the back of listening spot curtains will do the job just fine.
 

tuskenraider

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I decided to buy some custom sized "soundproof" curtains to help with reflections and slap echo. Besides the noise reduction claims, there wasn't anything else scientific posted about them. I can say they are very thick, seem well made and do help with the slap echo I had in the room quite a bit. I took some measurements with REW with them open and closed, but I can't remember if I could quantify anything or not. The nice thing is you can open and close curtains to have a desired effect. Anyway, here's a link: https://www.nicetown.com/soundproof-curtains/
 

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mitchco

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nitro230

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Heavy theatre curtains have been used for acoustic improvement in performance venues for a long time. They don't do much for low bass, but are pretty effective for damping reverb time in mids and highs. The nice thing about them is if they are mounted on a track they can be pulled back for a more lively environment.


Hey, I’m actually also looking into adding acoustical curtains in my living room home theater and stumbled across this forum.

Looks like it the Saaria curtains you linked are pretty decently priced but other than that link I’ve never heard of them and couldn’t find any reviews on them. Do you have experience with them and recommend them?

Also, how do you think they would compare to these ones one found on Amazon which are significantly cheaper?
I’m fine spending the extra money if it’s a noticeable improvement but if they are pretty similar then I’d probably just go with Amazon.

Thanks!
 

Philbo King

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Hey, I’m actually also looking into adding acoustical curtains in my living room home theater and stumbled across this forum.

Looks like it the Saaria curtains you linked are pretty decently priced but other than that link I’ve never heard of them and couldn’t find any reviews on them. Do you have experience with them and recommend them?

Also, how do you think they would compare to these ones one found on Amazon which are significantly cheaper?
I’m fine spending the extra money if it’s a noticeable improvement but if they are pretty similar then I’d probably just go with Amazon.

Thanks!
It was 30 years ago when I was given some very heavy velvet curtains and hung them 12" away from the limestone walls of my basement studio at the time. It helped a lot with the acoustic issues in that room. But I don't have any recent experience with curtains for acoustics.
 
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