Bass Traps and diffusers on rear wall

[Scotmcg]

Hello,

My room is approx. 20x15. I was originally going to build in a smaller room 16 x 12 and I had a plan all set to go. Now with the bigger space I'm trying to use the same plan, just spaced out but its brought up a question.

See attached picture, should I build the diffuser with 5 modules and have huge corner traps at about a 25 degree angle like so:
(grey area is trap, don't want to get all detailed in sketch up until I'm sure)

5 MODULE DIFFUSER.jpg

Or, should I make the diffuse 7 modules big and have smaller corner traps at about a 35 degree angle? (Black area is the extra space the 2 extra modules would take up).

7 MODULE DIFFUSER.jpg

What's the better option?

Also, the little offset that the arrows in the picture are pointing to. It's only 6" deep. That shouldn't behave like another corner for bass to build up, should it? Do I need to do anything special with it? Should I make the trap even more angled to go past it and cover it up?

Thanks,

Scotty

[gullfo]

the front offset shouldn't be a problem. the one on the back (left) sticking out may cause unwanted reflections and diffraction on the corner - so adding absorption there will help with that.

[Scotmcg]

Thanks for the answer Glen. That second offset juts out about 17". I guess I'll put a small superchunk there and call it a day. Also, any opinion about 5 or 7 diffusor modules?

[Paulus87]

Thanks for the answer Glen. That second offset juts out about 17". I guess I'll put a small superchunk there and call it a day. Also, any opinion about 5 or 7 diffusor modules?

Could you recreate the offset on the opposite side, nudge the traps and diffuser along to accommodate, and then extend both corner traps out so that both "offsets" are behind the corner traps?

As for 5 or 7 fractals... well... it's up to you. What do you want to do? Here's my oversimplified opinion on it: Any amount of diffusion is going to colour the direct sound (which I am not a fan of) so how much colour do you want?

[Scotmcg]

That's not a bad idea Paul, keep it symmetrical and all. My only concern would be, in covering it up, it's not going to leave any real space for another hanger or anything but a light stuffing of insulation. Unless I come way out with the trap.

[Paulus87]

That's not a bad idea Paul, keep it symmetrical and all. My only concern would be, in covering it up, it's not going to leave any real space for another hanger or anything but a light stuffing of insulation. Unless I come way out with the trap.

Well all you need to do is stop HF reflecting off... I don't know the size of that bit which is offset but I'm assuming it's no wider than about 100mm, which means most of the frequency spectrum will diffract around it into your deep rear trapping anyway, and any frequencies that don't will be absorbed by the 100mm or so of absorbent. Just put some fluffy and make it look like it's part of the bigger traps. Making it symmetrical is definitely the way I would go.