Spreading out bass absorption

[dymaxian]

Greetings! Just spending some time thinking about distribution of bass absorption in both control and tracking rooms... I've got an idea for a great rear wall system in mind, but I'm wondering if putting the beef of the bass traps in the back will adversly affect the way the room sounds.

This is all theoretical, but here's the idea- All the walls would be inside-out construction, and in the back of the room would be a false wall with a 2' or 3' space behind it. The false wall would be fabric over 1" or 2" 703, with regular batt insulation between the studs, and the space would be stuffed with panel traps. Also, because the walls are built inside-out, the stud spaces would be turned into panel traps.

So between the rigid insulation spaced out from the wall by 3', the acoustical hangers, and the panel traps, I've got all 3 of this board's favorite low freq absorbers all in one place.

The rest of the room would be a combination of panel traps built into the stud spaces, or 703 strapped across the faces of the studs and covered in fabric and/or slats. The front of the room would be almost all-reflective- probably mostly panel traps. But even so, more than half the bass absorption will be in the back wall.

Does this sound like a mistake? I know the idea is generally to have sound go past your head and not come back, and I think this would achieve that goal nicely.

Let me know what you guys think...

Kase
www.minemusic.net

[Jai]

dymaxian,

Great question to get us all thinking. My only fear would be front corner bass buildup. I remeber sometime seeing pixs of this room, right? but I really can't remember the space. What does the front of your room look like, sound like,? I have always spread out the "Love", ah or um I mean, bass traping. Every studio I have built i keep adding more and more hangers and traps. Then I found this site and started adding more. My last creation found hangers in the HVAC sofits along the length of the room at ceiling ranging from 6" to 18" tall and 18" wide, I think 20 per side. Then back wall is a variation of a slat resonator 10" deep to 2" deep with 4" 703. behind that, with openers at floor up 24" ,703 covered fabric, into a 30" cavity that has 9' x 28" hangers, then front of room I sofit mounted my 55" Big Screen TV, on the sides is another 5 hangers per side at 7' x 20". Then put in a cloud on the ceiling above mix that is 6' x 6' . i started the front at 2" from ceiling then leveled the cloud (MY ceiling slants up) so the back of the cloud is 12" from ceiling. Filled with 4' 703. Of all the steps, the cloud above mix position Really, Really made a diference in a nice tight low end. I tested every piece going in, before , then after. The cloud makes the room.

i know this is a lot of extra info from your question, but I felt I have seen most rooms with similar traping and not too many with a focused traping system. i would fear like I said a very uneven response of the room.

my 2 cents,

jai
www.themixstudio.com

[dymaxian]

It's not so much that the bass trapping would be focused... It'd be broadband absorption, and there would be plenty of stuff spread thruout the rest of the room. I guess I was wondering if there'd be any adverse effects to putting this much bass absorption concentrated in the back like that. I don't know if piling up 3 systems like that would reduce the efficiency of the different parts.

For example, would the panel traps built in back there be doing all that much work by the time low feq sound got thru the rigid fiberglass and acoustic hangers?

Kase
www.minemusic.net

[Jai]

Ohhhhhh I see the question now

I think the panel traps would be a waste of material. use them elsewhere in the room where you have nothing. By the time your low end reaches them through the 703/hangers/3 feet of traped air, I do not think they would benefit the sound. Kinda a point of dimminishing returns. Yes, there would be some help to it all, but what the 703/hangers don't get coming in, they sure as hell will get on the bounce back out....... If your back wall is absolutly rigid. 2 layers of 5/8", etc. As you know, if the back of all this isn't rigid, your bass is gonna just keep goin' til it hits something to stop it or the air diminishes it. But who am i tellin'. But, i am in a stage of a Studio B i am building right now. We have the back wall ready to hang our traps, and I have material to make a few panel traps in the other parts of the room, If you have a day or two I will put the panels in the back of the trap, hang the traps, and put 703 in the studs. I wont fabric it so I can pull the panels back out, but the fabric shouldn't make a bit of diference. i will do it with and without. I have the time cus we are waiting on some other materials to finish out some other things. I can shoot the room before, after, and after I pull the panels back out. This is the stuff I come here for. Experiments.

Hope any of this helps.

jai
www.themixstudio.com