Small room 12x7x7

[TheMegaMan]

I currently have this small room to mix and record vox it's 12 feet long, 7 feet wide, and 7 feet tall.

I have 2x4 bass traps 4 inches OC703, one trap in each corner, and 6 other similar traps around the room.

My mix position is facing the far wall about 3 feet away from the wall.

Couple of Qs:

a) How many additional bass traps should I add to make this room workable.

b) Should the traps be hung on the wall, or can you just stand them up from the floor?

c) is diffusion doable in this small space? I definitely have some undesirable flutter echo and comb filtering going on.

d) is a space two feet wider, but the same length and height, going to make a difference worth moving to

[Ethan Winer]

a) Ideally, as many as will possibly fit.

b) Reflection panels work best at ear height. Bass traps work best straddling entire corners from floor ceiling.

c) Yes, but good diffusors cost more than good absorbers whether you buy commercial products or DIY.

d) Yes, if it's not a lot of effort. That avoids the two same 7' dimensions.

--Ethan

________________
The Acoustic Treatment Experts

[TheMegaMan]

Thanks Ethan....

From reading your site you make a point about rooms that are smaller than 10 by 10 and state that it is better to make the room completely dead at this size bc the reflections are too short to be useful.

Do you recommend that for my 12x7 room, and thus how does diffusion come into play here if a room this small is best made completely dead?

What's a shame is it has a great wood floor but as you have explained it's rendered useless in my tiny space.

Thanks again you guys here are INCREDIBLE.

[Ethan Winer]

^^^ Yes, you should treat much of the room's surfaces, but you could still use diffusion to make it sound a little larger if the higher cost is not a problem. The standard place for diffusors is on the rear wall behind you.

--Ethan

[obliterations]

Originally Posted by Ethan Winer

^^^ Yes, you should treat much of the room's surfaces, but you could still use diffusion to make it sound a little larger if the higher cost is not a problem. The standard place for diffusors is on the rear wall behind you.

--Ethan

Ethan, I have a similar room 6'4" wide x 12' long and 7' high. I was wondering about the corner traps. Do they have to be triangular? or could I put four 4x16x7 traps flush against the wall pushed into the corners?

Thanks

[Ethan Winer]

Originally Posted by obliterations

could I put four 4x16x7 traps flush against the wall pushed into the corners?

Is that feet? Inches? Centimeters?

Traps work well flat on the walls, but they have to be thicker than when straddling corners. If you can manage 6 to 8 inches thick that will work pretty well.

--Ethan

[Spotty]

Interesting to read this conversation as I am thinking about the same things and in context with a similar room. So if I understand correctly; the usage of as much bass traps as possible isn't going to result in problems with the mid and high frequencies? I remember that such things have been mentioned here at the studio building / acoustics forum. Strange that such conflicting information is spread. I am really interested in the opinion of someone who really knows what he's talking about though; so Ethan I would certainly appreciate it if you could point this out shortly.

[Ethan Winer]

^^^ Bass traps can absorb all frequencies or just bass frequencies. With the latter it's not possible to have too many in most room. But with plain rigid fiberglass and foam etc you probably can make a room too dead.

--Ethan

[Spotty]

Thank you, that information is very welkom, I do appreciate it. I have been reading seriously about acoustic treatment lately, but it seems hard to get explicit answers to some issues. Your answer leaves me with the following question; what determines if a bass trap absorbs all frequencies or just bass frequencies? Because reading left me with the impression that basstraps absorb high/mid frequencies just like broadband treatment, plus absorbing bass frequencies because of their greater thickness.

[Ethan Winer]

Originally Posted by Spotty

what determines if a bass trap absorbs all frequencies or just bass frequencies?

The product's acoustic test data. More here:

DIY material:
Density Report

Commercial products:
RealTraps Product Data

More on acoustic testing:
Test Methods for Acoustic Treatment Products

--Ethan

[Spotty]

Thanks for the links, and of course you´re right. Only I was thinking about certain (physical) characteristics that determine the testdata. Anyway, appreciate your replies, thank you for the effort.

[Spotty]

Oh, and I read the FAQ section of your site this morning, got some pieces of information that I was looking for from there as well.

[TheMegaMan]

Alright guys this is my room response. Room One is closed door in the back of the room.

Out of curiousity I wanted to see what would happen if I kept the back door open, allowing sound out into an awning that adjacent to large glass windows. Just for shits and giggles.

[TheMegaMan]

And door open

[Ethan Winer]

Originally Posted by TheMegaMan

Alright guys this is my room response.

LOL, sorry, here another link you'll find useful:

Room Measuring Primer

I post this link because it explains why third octave averaging is not useful for LF response graphs. Turn that off to show the true response, then maybe re-post the graph.

--Ethan

[TheMegaMan]

Ethan: 1/24th smoothing

[TheMegaMan]

So I moved my listening position, added four inches off the wall to the back wall bass traps, and hung my DIY cloud.

In moving the listening position Im losing a bit of stereo image bc my equilateral triangle is no more by moving my position back. Going to get some monitor stands though to solve this issue, and a wireless keyboard and mouse is now in order.

These are the newest results:

[Ethan Winer]

Originally Posted by TheMegaMan

Ethan: 1/24th smoothing

Now you can see that the span from null to peak on either side of 100 Hz is really about 30 dB rather than only 15. You can also see that the null and peak are both narrower than the earlier graph shows.

--Ethan

[Glenn Kuras]

Do you recommend that for my 12x7 room, and thus how does diffusion come into play here if a room this small is best made completely dead?

As Ethan said diffusion could work for you in this room, but I would start with taming the low end frequencies first and then add diffusion as a 2nd step. The shape off your room is going to take a lot of trapping to get it under control.

see the following on diffusion.
GIK Acoustics presents "How Diffusion Works!"

[MyPutzyRod]

Glenn and Ethan:

A small room such as this size or slightly bigger (13x7.5x9) once sufficient bass trapping has been added and a reasonable result in the low end is achieved, what type of diffusion would be sufficient given the 38% rule at the mix position?

In other words, the listening position is exactly 8 feet from the back wall. What design works best given those dimensions? By the way I have orders into both of your companies shortly for a combo of products (already popped my GIK cherry though!)

[Jens Eklund]

Originally Posted by MyPutzyRod

A small room such as this size or slightly bigger (13x7.5x9) once sufficient bass trapping has been added and a reasonable result in the low end is achieved, what type of diffusion would be sufficient given the 38% rule at the mix position?

http://www.gearslutz.com/board/6214094-post2.html
http://www.gearslutz.com/board/6124899-post6.html