Hi everyone.

1. I have been watching real trap's video "The Ultimate Home Studio". They talk about that the ceiling in the studio absorbs 100 %. Is this really possible and are we talking about the hole frequency range? Does anyone know what rigid fiberglass is used?

2. I have read that small rooms are better without diffusors. If so, what room size is better with diffusors?

/ Per from Sweden

1. The ceiling is stuffed with R38, which is fluffy fiberglass (not rigid) 12 inches thick. That absorbs 100 percent to below 100 Hz, then less and less at lower frequencies.

2. It's difficult to give an exact cut-off size. I'd say a room the size of a bedroom is probably not a good candidate for diffusion. Though I've heard of some pro studios using diffusors even in small booths. Good diffusion is expensive to buy (or complicated to build), so most people go with absorption unless they're willing to make a serious investment in their room.

--Ethan

Thanks a lot for the answer Ethan.

1. Where can I buy these R38?
With this solution it shouldn't matter how low or high
ceiling you got right?

2. Ok but the control room in the video didn't look that big
and you used diffusors!

I would say in a small room you want to start with absorption in the key spots then after "all is good" you can add diffusion on the back half (behind listening spot) of the room.

Any home supply store.


Yes, it works well with low ceilings.


Doug's control room is 16 feet from front to back, so it's definitely large enough for diffusion. I recently tried diffusion all over a small room, as shown here:

Hearing is Believing

The diffusion worked so well I'm shooting a video version of the above article this weekend.

--Ethan

What about if we first treat a small room using fullrange absorption in the corners and FRP (for RFZ) and when everything is ok we start to put diffusers in the remaining space?

regards
Leonardo

Acoustics is half science and half art. Diffusors work well in a lot of places in a room, though they are most common on the rear wall behind you.

--Ethan

Considering this distance from the rear wall:



Do you think I would benefit using difusors instead absorbers? Some times I have a feeling that the space behind me is too quiet.
What's your opinion about this kind of diffuser?




thanks!

That's pretty close behind you, but I'd probably go with diffusors there anyway. Hard to say what you'll prefer. This is the tough part, because the only way to know is to buy diffusors and buy absorbers and try each. Those diffusors look like genuine QRD types, and that's fine.

Maybe ask kitty for an opinion?

--Ethan

Another way to go about it, is to put THICK absorption (I like 6") right behind you (maybe cover a 2'x4' area) and place diffusion around that. Keep in mind that there are HUGE LF nulls and peaks coming from that back wall which will make the low end unclear.

Hey GIK,
good idea. I have already ordered 2 of these diffusors and I will do some tests. I will update the topic of my room as soon as I have updates.

thanks you very much!
Leonardo

Hmmm. Are we witnessing Ethan getting a different opionion on diffusion after this experiment? Definetly seems like it.

I've tried to debate this before. I know there's been some studies here in Scandinavia about treating a room and what people prefer. Treating the room with helmholtz resonators for the low end, some absorption for midbass and only diffusion from 500Hz and up seem to be the absolute ideal and what people prefer rather then much broadband absorption. Yes, this is of course a much more expensive way to treat the room. But if money isn't a hindrance, do both you and Glenn from GIK agree that this is the best way to treat a room?
Are you aware for any studies that show what's preferable?

Not really. I've been a fan of diffusion for many years, though more recently I've questioned the "conventional wisdom" that diffusors must be farther away.



There may be studies, I honestly don't know. Acoustics is as much an art as a science, and so personal preference is often a factor. BTW, yesterday I replaced the Hearing article linked above with this video version:

Hearing is Believing

The recording made in the rear of the room lets you hear the effect of all the diffusion, and it's definitely clearer and less colored sounding than bare walls. In the room the difference was even more striking, but you can hear it in the recording on the video too.

--Ethan