Acoustically treating a small room for mixing

[johnjm22]

The Problem: I need to Acousticaly treat my less than ideal bedroom for mixing music.

Room Dimensions: 144" long, 128" wide, and 94" high.

What I have: 12 24"x48" 1.5" thick foam wedges.

How should I go about placing my foam wedges? I've never "treated" anything before so I don't really know what the hell I'm doing. Is there any basic guidlines or princaples I should be following?

I know I still need to get bass traps but I'm not sure which ones to get. I can't really afford the Realtraps ones right now ($299 each). Does anyone know of any good more cost effective traps? I was looking at these ones; http://cgi.ebay.com/ws/eBayISAPI.dll...328011393&rd=1

Any advice would be greatly appreciated.

Here is a diagram I made of the room:

[u b k]

build as many of these as you can afford:

http://www.pmerecords.com/Broadband.cfm


go here and read as much as you can, ask questions, and *listen* to the answers:

http://www.musicplayer.com/ubb/ultim...orum/f/26.html


the necessity for experimentation with monitor placement and listening position cannot be overstated.

give the foam away; it will only make everything that's already wrong, worse. you need broadband absorption in the bass freqs only, with very light absorption and diffusion of the hi's. foam will suck up all your hi's and leave the bass an untouched mess.

put the foam down and back away slowly!


gregoire
del ubik

[norman_nomad]

Originally Posted by johnjm22

I've never "treated" anything before so I don't really know what the hell I'm doing. Is there any basic guidlines or princaples I should be following?
:

Go to this site: www.johnlsayers.com. Spend the next two weeks reading posts.

Stuffing Owens Corning FRK 703/705 in all of your bedroom corners (ceilings are corners too) is enough to get started, but not nearly enough to know what you're doing, why, and how you might improve things!

Good luck and keep us posted!

- Damon

[pan60]

i would also recommend the www.johnlsayers.com site.

[warhead]

You could submit this to Auralex and they'll get back to you with suggestions:

http://www.auralex.com/pcf/

Ethan Winer is a great resource as well.

War

[tINY]

It's important to know the structure of the walls too. Hard plaster could be a nightmare in a room that size. Gypsum board on 16" or 24" centers already gives you some transmission loss at the low frequencies (this is a good thing if you aren't disturbing anyone...).




-tINY

[johnjm22]

Thanks for all the replies everyone. I'll check out some of those links.

Originally Posted by u b i k

give the foam away; it will only make everything that's already wrong, worse. you need broadband absorption in the bass freqs only, with very light absorption and diffusion of the hi's. foam will suck up all your hi's and leave the bass an untouched mess.

put the foam down and back away slowly!

What's so wrong with foam?

I've seen pics of a lot of control rooms and most all of them have some sort of foam wedges. And nearly all "room kits" include foam wedges of some sort. Your the only person I ever heard say this.

Please Explain.

[captain54]

Originally Posted by johnjm22

Thanks for all the replies everyone. I'll check out some of those links.

What's so wrong with foam?

I've seen pics of a lot of control rooms and most all of them have some sort of foam wedges. And nearly all "room kits" include foam wedges of some sort. Your the only person I ever heard say this.

Please Explain.

the latest MIX magazine has a feature on the some of the top control rooms in the country,and I don't think I saw one foam wedge....


dude, you need to do a lot more research on this topic before you start forking out money for useless materials....

foam is only useful across a portion of the frequency spectrum.....if you overdo the foam, and ignore the mid lower to lower end frequencies that foam has no effect on, you are going to have a real mess on your hands...

[BJohnston]

Find some Owens Corning 703 or 705 and build the traps yourself. The corners are probably the most important to treat. At least that's what I've found. Definitely check out some of the articles mentioned by the other guys along with
www.ethanwiner.com

B

[Ethan Winer]

John,

You already go plenty of good advice, and maybe I can add a little more.

> How should I go about placing my foam wedges? I've never "treated" anything before so I don't really know what the hell I'm doing. Is there any basic guidlines or princaples I should be following? <

The short version is you need as much bass trapping as possible in the corners, and mid/high frequency absorption at the first reflections points on the side walls and ceiling. If you have large areas of bare parallel surfaces, you need to treat some of those too to avoid flutter echo. For the complete story see my Acoustics FAQ:

www.ethanwiner.com/acoustics.html

> I can't really afford the Realtraps ones right now ($299 each). <

My company's MiniTraps are only $199, and they are far far superior to most other commercial solutions.

> Does anyone know of any good more cost effective traps? I was looking at these ones <

Looking at the data on that page this looks like another alias for Foam by Mail, who have been proven to use "fabricated" data. You can see that proof on the Product Data page of the RealTraps site, which shows the results of lab tests done at IBM on corner foam:

www.realtraps.com/data.htm

Look at the two brands of corner foam and see how they compare to each other (and to RealTraps), even though both brands of foam claim identical absorption. If you have a moment, contact that eBay vendor and ask them to send you the official lab data for their absorption tests. I'd be curious to hear they say.

> Here is a diagram I made of the room <

Your placement of the speakers and mix position is exactly perfect.

--Ethan

[AnalogUniverse]

i posted these sites in another thread as well, but, here they are again : )
http://www.bobgolds.com
http://forum.studiotips.com

lotsa good info (in addition to what was already posted ^^ )

[johnjm22]

Ethan, I'm so glad you replied. I've been reading your article at www.ethanwiner.com/acoustics.html and it's awsome! I've been learning so much.

Originally Posted by Ethan Winer

My company's MiniTraps are only $199, and they are far far superior to most other commercial solutions.

Yeah I plan on getting six of those and four mondo traps, but I can't really afford it right now.

I might have to settle for some of these: http://www.pmerecords.com/Broadband.cfm

Originally Posted by Ethan Winer

If you have a moment, contact that eBay vendor and ask them to send you the official lab data for their absorption tests. I'd be curious to hear they say.

Will do.

Originally Posted by Ethan Winer

Your placement of the speakers and mix position is exactly perfect.

--Ethan

I saw that article in EQ magazine "Shootout at EQ Corral" in which you placed the listening position 38% back, so I figured I'd do the same.

My room is actually pretty similar to that room. So I'll probably treat it much like you did. But since my room will only be used for mixing stereo (not surround) I can get away with less traps right?

[johnjm22]

I sent that ebay vendor a request for the official lab data for thier absorbtion tests, and this is what they sent me:

"Hello,
The NRC rating is listed below...

Bass Absorbers
Overall NRC 1.35
NRC at 125 HZ 1.25
NRC at 250 HZ 1.26
NRC at 500 HZ 1.47
NRC at 1000 HZ 1.42
NRC at 2000 HZ 1.24
NRC at 4000 HZ 1.29"

It's they exact same thing they listed in the auction.

[Bang]

I'd get a bunch of Realtraps and Mini traps.. or you can make a bunch of 4 inch absorbers like described above however for the corners, I'd put a box of twelve 2 inch pieces of 703, just leave them in the box and cover it with fabric. Best and easiest bass trap you'll ever find.

Steve
www.bangrecording.com
www.blacklinerock.com

[u b k]

Originally Posted by johnjm22

What's so wrong with foam?

I've seen pics of a lot of control rooms and most all of them have some sort of foam wedges. And nearly all "room kits" include foam wedges of some sort. Your the only person I ever heard say this.

Please Explain.

i'm guessing that now that you've read more posts, and have been digging into ethan's materials (ethan is nothing less than a saint, and his saintly humility would lead him to deny this), you're beginning to see that i'm not the only person who advocates losing the foam.

the reason you never heard it before is because most of the info people get exposed to is from companies who sell foam and, as you say, 'room kits' loaded with foam. the truth is that you will never see a piece of foam in any control room designed from the ground up to be a control room, because the folks who know about acoustic science know that foam is a bad solution to a worse problem, and they know that far better products exist for any anomalies a room might have.

small rooms are very predictable in terms of the problems they present. rigid fiberglass or rockwool panels, lots of them, all over the corners, are the closest thing to a panacea i've ever heard.

hopefully, this can also serve as a gentle wakeup call for you, insofar as you live in a society that is drenched to the bone with commercial interests, marketing, and economic agendas. be very aware of how you are inundated with hype masquerading as information; it's easy to believe that because you've heard and seen something a few million times, and a market is flourishing in support of it, it must be true.

in any case, good luck with your room! you've got a lot of good info to work with now.


take care,

gregoire
del ubik

[Ethan Winer]

John,

> I sent that ebay vendor a request for the official lab data for thier absorbtion tests, and this is what they sent me <

But no PDF file or Word doc or anything stating the name of the lab, sample size, date of testing, etc, right? Gee, what a surprise...

--Ethan

[Jay Kahrs]

Originally Posted by Ethan Winer

> Here is a diagram I made of the room <

Your placement of the speakers and mix position is exactly perfect.

--Ethan

I don't know...what about the large window to the left of the mix postion? Wouldn't reflection's off that be a mess? What about relocation the mix postion to be in front of the window? Granted, it's the short throw of the room but I'd think that reflections would be easier to control especially with diffusion in the rear wall.

[johnjm22]

Originally Posted by u b i k

i'm guessing that now that you've read more posts, and have been digging into ethan's materials (ethan is nothing less than a saint, and his saintly humility would lead him to deny this), you're beginning to see that i'm not the only person who advocates losing the foam.

Yup. You were right. Thanks for steering me in the right direction.

Originally Posted by ethan

But no PDF file or Word doc or anything stating the name of the lab, sample size, date of testing, etc, right? Gee, what a surprise...

Nope, nothin. But I'll ask them for the Lab, Sample size, ect. and see what they say.

Originally Posted by Jay Kahrs

Wouldn't reflection's off that be a mess? What about relocation the mix postion to be in front of the window? Granted, it's the short throw of the room but I'd think that reflections would be easier to control especially with diffusion in the rear wall.

The window is covered with a curtain, which provides about a five inch air gap. So I don't think it will be a problem.

[Jay Kahrs]

Originally Posted by johnjm22

The window is covered with a curtain, which provides about a five inch air gap. So I don't think it will be a problem.

As long as the cloth is dense enough it won't be a problem, but I'd hang another one on the other wall so there's a mirror image.

[johnjm22]

Originally Posted by Jay Kahrs

As long as the cloth is dense enough it won't be a problem, but I'd hang another one on the other wall so there's a mirror image.

Good Idea.

[Ethan Winer]

Jay,

> what about the large window to the left of the mix postion? <

That's easy enough to treat with a single absorbing panel on a stand at the first reflection point. Or even a heavy curtain that can be opened while tracking and closed for mixing. Then the speakers can remain where they are, which is better for the low end.

--Ethan

[Ethan Winer]

John,

> I'll ask them for the Lab, Sample size, ect. and see what they say. <

Please do. I think it's about time those guys learned that we're on to them.

--Ethan

[seawell]

If you don't really want to build your own traps then I highly recommend these:

GIK Acoustic Panels Ebay Auction




They are available in 2" or 4" thick panels. Also in black or natural white fabric.
I own 8 of them and they have really made a difference in my studio.

[Bang]

Just curious, what kind of fabric is on those GIKs? Felt?

Steve
www.bangrecording.com
www.blacklinerock.com

[seawell]

Originally Posted by Paul David

Hey those remind me of some other traps. I'm trying to remember the name of those other ones???


Oh yeah, they're called REAL TRAPS!!!

Ethan, does this bug you? I mean, you develope Real Traps, spend a lot of your time educating people about acoustics, and then these GIK jokers bite your whole style and under cut your price.


This was my favorite part of the ebay ad:

"Problem is that most rooms take away from the experience due to knolls in the room. GIK Acoustic Panels are designed with the same material that is used in today’s professional recording studios, giving you a life like sound – for a fraction of the cost. Similar panels range from $90.00 to $300.00 each!!! "

Those knolls in my room are giving me FITS.

I never meant for these to be a suggested replacement for Real Traps. That's why I started out my post by saying-"If you don't really want to build your own traps, then I highly recommend these:" I didn't say-"If you don't want to buy Real Traps then buy these." Real Traps to my understanding have more going on inside of them than just rigid fiberglass. These GIK traps are just rigid fiberglass attached to a wooden frame and covered in a canvas type fabric. I think the GIK's are great if you don't have the time or resources to build your own. I don't think for a second that they are as effective as real traps and I didn't mean for it to seem that way. I don't have any personal connections to GIK, I'm just a guy who bought 8 of them off of ebay and like how they have improved the sound in my studio so, I thought I would pass along the info. thumbsup

[Ethan Winer]

Paul,

> Ethan, does this bug you? <

Nah. If anything, I'm thrilled to see people finally understanding the importance of treating their room, and especially the importance of bass traps. I've been spreading the word about this for ten years now, since long before I was in the business. And as Seawell said, our products are more than just rigid fiberglass, and they absorb more at low frequencies.

I'd much rather see someone buy from another company than do without.

--Ethan

[DirkB]

In a room that small, no matter how good the basstrapping, you're still going to be left with lowend problems. I'd invest in some great monitors that are tight in the lowend. In my smallish room (11x16) I have all the treatment that I can get, but the blooming bass of my old HR824's always made me struggle to get the bass right. Since I switched to S3A's, the room problems are of course still the same, but due to the mega tight bass, it's somehow less of a probem than it was with the Mackies. The first mixes I did translated spot on and for the first time I feel confident to realy dig in with eq and compression into the lowend.

So, although I'd highly recommend you get your room as good as possible acoustically, don't overlook the fact that speakers can make all the difference...

Good luck,
Dirk

[johnjm22]

Originally Posted by Ethan Winer

John,

> I'll ask them for the Lab, Sample size, ect. and see what they say. <

Please do. I think it's about time those guys learned that we're on to them.

--Ethan

I got a response from them today. They gave me some pretty useless information.

"Hello,
The type of foam we use is Charcoal firm foam. And the spec of this foam is....
Color : Charcoal
Life : 8-10 years
Density (Lbs./Cubic Ft.): 1.7
25% IFD (Lbs): 70
Support Factor (65%/25% Min.): 1.90
Air Flow (CFM) Min.: 3.00
Tensile (PSI) Min.: 10.0
Elongation (%) Min.: 150
Tear (PPI) Min.: 1.00
Resiliency (%) Min.: 25
Fire ******ant Classification: Calif. TB #117
Now as your question for the official lab data for your absorption tests I do
not have it available at this time. We get this type of foam from a manufactory
company, which they have provided me with the NRC rating information, so I would
have to call them with this information and see what they can do for me.
Thanks,
Christina
(248)-284-0002
sales@foamshop.net

Please Visit The Web Site!
http://www.foamandupholstery.com"

[pan60]

dose not foam degenerate, or brake down, and become a crumbling mess in most sound environments?
i was under the impression foam vibrates to absorb sound energy, movement, friction, heat, now breakdown.
maybe Ethan Winer could shed some light, i have stayed clear of foam because of this belief.

[Ethan Winer]

John,

> They gave me some pretty useless information. <

Indeed, this is my favorite:

We get this type of foam from a manufactory

Yup, I bet that's exactly where they get it from.

Thanks.

--Ethan