Fabric as room treatment

[rockinrocker]

OK, from what I understand fabric/curtains can work well for room treatment, as long as it's heavy enough. Is that correct? Are there any other considerations here? What type of material and so on?

I have access to a large piece of heavy fabric that i'm thinking of covering with muslin left over from covering my rock wool in order to make a large, heavy curtain.

And also, being some distance away from the wall will actually increase effectiveness, right?

Basically, the space I'm trying to cover is a sort of recessed area that's about 15' long and about 4' deep. Would it work well to hang my "curtain" over that area in order to tame reflections and the like?

Thanks.

 

[Ethan Winer]

OK, from what I understand fabric/curtains can work well for room treatment, as long as it's heavy enough.

Fabric is good only to absorb high frequencies. To get down to the bass range you need something a lot thicker than fabric. It's important to absorb all frequencies evenly, not just mids and highs. Otherwise you risk making the room too dead, yet boomy at the same time.

--Ethan

 

[rockinrocker]

Hi Ethan,
thanks a lot for the response.

does it matter that i'd be using the curtain along with a considerable amount of rock wool? i've got 4 inches straddling all the corners floor to ceiling and 2 inches in 2' by 4' pieces on the walls.

from what the room sounds like to me, deadening some highs is would actually help (totally subjective of course....)

 

[The Axis]

I would recommend doing some reading before "treating" your room.
Maybe "Master Handbook of Acoustics"

http://www.amazon.com/Master-Handbook-Acoustics-Alton-Everest/dp/0071360972

Deadening a room is not necessarily desireable.
Room "treatment" should be geared towrds correcting gross defects, not necessarily looking for "general improvements".
Most home studios are simply limited by the high Q resonances and standing waves that occur due to approximately 8' ceilings

One way around this, if you can pull it off, is to have the recording be located exactly in the geometric center of the room, since all resonant modes will be cancelled at the center.

Notice that great concert halls are usually:
1. A lot BIGGER than a home studio. This puts the fundammental resonant modes below the hearing band.
2. Have SLOPING ceilings and or floors, and non-parallel walls so that standing waves don't set up.
3. Have a variety of textures so that no set of frequencies is damped preferentially.

 

[Dags]

OK, from what I understand fabric/curtains can work well for room treatment, as long as it's heavy enough. Is that correct? Are there any other considerations here? What type of material and so on?

Basically, the space I'm trying to cover is a sort of recessed area that's about 15' long and about 4' deep. Would it work well to hang my "curtain" over that area in order to tame reflections and the like?

Thanks.

Hey there rr.

I have had pretty good success with using the ripple foam that is commonly used as mattress overlay. The last place I was in I had covered almost every single surface in it! I'm being a little bit more conservative now that I know this isn't really necessary
The rockwool will shed itchy fibres unless you're able to really seal it up tight inside the fabric. Something you don't want is an excess of dust particles floating around your expensive gear.
Ethan Winer makes a good point that fabric will only cut out the higher end of the reverberant spectrum, unless it is a really thick and heavy curtain such as those used in theatres.
The foam mattress material works a bit better to dampen the walls I have found.
The recessed area may be subject to low end resonance if it is kind of 'boxy' and the only thing that will knock that out is really dense stuff. The R2.5 rockwool is excellent at really stopping dead everything, but as I said earlier, I couldn't stand having it exposed on the walls as it does create a lot of dust.
A mate of mine stood some wire sprung mattresses up against the walls which created a fantastic little area for recording in. No reverb at all!

Good luck!
Dags

 

[Adam P]

Whatever you use, make sure its nonflammable.

 

[Lectric_Lab]

I've been using heavy curtains in my vocal booth for along time, they are approximately 6 inches off wall surface with aurelex behind them, for my vocal booth it works well, and is a dead sounding space, all recording space shouldn't neccesarily be dead though as stated previously, some rooms are better sounding lively. My live room has wood floors, and a rug here and there, I use bass traps, and mobile gobos as needed. If you just have a recess that is of no value, why not frame it in and double dry wall the surface area. Then treat the new wall if needed.

 

[The Axis]

General subject of room "treatment":
I happened to attend a concert at Gardner Hall, at the University of Utah last night.
I was marveling at how they had gone to extreme lengths to "randomize" the shape of the room. The walls and ceiling actually have waves built into them, and then they are covered with panels that contain apparenly randomized width, heights, and lengths of raised ridges.
All surfaces were hard, no fabric or soft covering. (Of course the floor, filled with an audience, is sort of a "soft cover" on one surface)
I got some pics. If I get time I will upload them.

 

[Micter]

Hey there rr.

I have had pretty good success with using the ripple foam that is commonly used as mattress overlay. The last place I was in I had covered almost every single surface in it! I'm being a little bit more conservative now that I know this isn't really necessary
The rockwool will shed itchy fibres unless you're able to really seal it up tight inside the fabric. Something you don't want is an excess of dust particles floating around your expensive gear.
Ethan Winer makes a good point that fabric will only cut out the higher end of the reverberant spectrum, unless it is a really thick and heavy curtain such as those used in theatres.
The foam mattress material works a bit better to dampen the walls I have found.
The recessed area may be subject to low end resonance if it is kind of 'boxy' and the only thing that will knock that out is really dense stuff. The R2.5 rockwool is excellent at really stopping dead everything, but as I said earlier, I couldn't stand having it exposed on the walls as it does create a lot of dust.
A mate of mine stood some wire sprung mattresses up against the walls which created a fantastic little area for recording in. No reverb at all!

Good luck!
Dags

100% disagree

Matress foam doesn't do much in the way of mids and lows. It's really not much better than curtains.

Curtains will only work on highs. No exceptions! They aren'e dense enough to do anything on mids let alone lows.

Rockwool isn't itchy at all. Fibreglass is however. Rockwool will only work to around 80hz or so usually more like 100hz . That leaves some subsonic lows to be a problem.

Matresses? Don't get me started.

 

[I88]

This helped me out a bit, so thanks!

 

[Dags]

100% disagree

Matress foam doesn't do much in the way of mids and lows. It's really not much better than curtains.

Curtains will only work on highs. No exceptions! They aren'e dense enough to do anything on mids let alone lows.

Rockwool isn't itchy at all. Fibreglass is however. Rockwool will only work to around 80hz or so usually more like 100hz . That leaves some subsonic lows to be a problem.

Matresses? Don't get me started.

Maybe I just have sensitive skin, but I found all the crap that falls from the rockwool to be really irritating when I was putting it in the ceiling & walls.
I couldn't wait to get in the shower and wash it off. And yes - fibreglass is even worse!!

The ripple foam does only prevent the room from ringing (high and upper mid absorption) but this is a good start for taming a room on a budget and yes, he will certainly need something to prevent the low-mid frequencies from bouncing. I have a suede couch and some chests of drawers filled with crap that work a treat

(and my friend using the wire-sprung mattresses set it up as a temporary measure to get a vocal take while the singer was over from interstate. I wasn't there when he did it so I can't tell you how effective it was from personal experience. However the vocal ended up on the album so it must have worked for him)

rockinrocker - what did you end up doing and how effective was it?

Dags

 

[SouthSIDE Glen]

Rockwool isn't itchy at all.

Maybe some forms of it, I don't know. But I gotta tell you, in the first room I built waaaay back when, we put some rolled rockwool in between the ceiling studs and outer wall studs (as much for temperature insulation as anything else), and even with long sleeves and gloves and trying to be careful the whole time, we were itching like hell before all was said and done.

G.

 

[Micter]

Maybe some forms of it, I don't know. But I gotta tell you, in the first room I built waaaay back when, we put some rolled rockwool in between the ceiling studs and outer wall studs (as much for temperature insulation as anything else), and even with long sleeves and gloves and trying to be careful the whole time, we were itching like hell before all was said and done.

G.

In my early 20's I was an insulation installer. Never had any itching from rockwool. Maybe the difference is I used to blow it rather than install batting. It doesn't make sence cuz blowing insulation is a lot messier.

 

[SouthSIDE Glen]

In my early 20's I was an insulation installer. Never had any itching from rockwool. Maybe the difference is I used to blow it rather than install batting. It doesn't make sence cuz blowing insulation is a lot messier.

Well, I'm not an insulation specialist, by any means. All I can go on is that one experience with the Owens Corning batting. My buddy's father, who was kind of supervising us a bit at the time (we were only 19 at the time...this was 1979) had warned us beforehand about the itching. We wore long-sleeved flannel shirts and work gloves and this stuff still got real irritating real quick, especially on the forearms where the stuff snuck in under the shirt cuffs..

Maybe there's been some changes to rockwool's formulation or something since 1979, or maybe the blown stuff is treated with something different or something, I don't know. All I can say was that we were pretty miserable for a few hours after that installation.

G.

 

[TexRoadkill]

Hey there rr.

I have had pretty good success with using the ripple foam that is commonly used as mattress overlay. The last place I was in I had covered almost every single surface in it!

I appreciate your good intentions but why do you keep pushing that crap? It just makes the room sound muddy and it's a waste of money and time. Wall treatment is like an EQ and if you roll off all the highs it usually sounds like crap.

It's also dangerous. Haven't you seen the videos from the Great White concert fire?

 

[Dags]

I appreciate your good intentions but why do you keep pushing that crap? It just makes the room sound muddy and it's a waste of money and time. Wall treatment is like an EQ and if you roll off all the highs it usually sounds like crap.

It's also dangerous. Haven't you seen the videos from the Great White concert fire?

Nope - send me a link.

Guys, I'm not pushing this stuff - I'm just imparting my experience of successfully using it to help treat a room when money is a limiting factor, and I'm in no way stating that its the only thing that needs to be used to control the whole spectrum of frequencies.
Yes, it may be a fire hazard, like curtains, carpet, my child's soft toys and just about everything else in my house, but I'm working in a non-smoking environment and don't have any amps or other heat sources near the panels I have put on the walls so I'm thinking that its pretty low risk.
If the ignition source is somewhere else in the house then its going to burn through the floor into my studio anyway.

I'll leave you all in peace now
Dags

 

[Todzilla]

I would recommend doing some reading before "treating" your room.
Maybe "Master Handbook of Acoustics"

http://www.amazon.com/Master-Handbook-Acoustics-Alton-Everest/dp/0071360972

Deadening a room is not necessarily desireable.
Room "treatment" should be geared towrds correcting gross defects, not necessarily looking for "general improvements".
Most home studios are simply limited by the high Q resonances and standing waves that occur due to approximately 8' ceilings

One way around this, if you can pull it off, is to have the recording be located exactly in the geometric center of the room, since all resonant modes will be cancelled at the center.

Notice that great concert halls are usually:
1. A lot BIGGER than a home studio. This puts the fundammental resonant modes below the hearing band.
2. Have SLOPING ceilings and or floors, and non-parallel walls so that standing waves don't set up.
3. Have a variety of textures so that no set of frequencies is damped preferentially.

You are correct, although we shouldn't discourage folks from making improvements. Done properly, acoustic treatment can make a big diff.