3 Unanswered Questions

[ThePrez]

This "Studio Building / Acoustics" forum is great I've learned so much over the past days. You guys answered all my questions, only three remain...

1. For the absorption panels in my vocal booth. Will 2" suffice, because the voice doesn't produce low enough frequencies? Or is a 4" a better choice?

2. Could I use this for aid around an vocal recording area? It would be nice have the portability. Your thoughts... click here for link.

3. What is the purpose of hanging diffusers like these above the console from the ceiling? I see it sometimes in studio? Is it because the ceiling is so high they need diffusers instead of a cloud type setup? click here for link.

[SAC]

Originally Posted by ThePrez

This "Studio Building / Acoustics" forum is great I've learned so much over the past days. You guys answered all my questions, only three remain...

1. For the absorption panels in my vocal booth. Will 2" suffice, because the voice doesn't produce low enough frequencies? Or is a 4" a better choice?

4" is a better choice with a 4" gap from the 'wall' boundary. The voice does produce fundamentals low enough to benefit from the 4" and lower than 2" will reasonably address.

Originally Posted by ThePrez

2. Could I use this for aid around an vocal recording area? It would be nice have the portability. Your thoughts... click here for link.

Such panels, configured as GOBOs - essentially panels on stands, can indeed be used in a myriad number of ways in live recording to contain specular reflections.

Originally Posted by ThePrez

3. What is the purpose of hanging diffusers like these above the console from the ceiling? I see it sometimes in studio? Is it because the ceiling is so high they need diffusers instead of a cloud type setup? click here for link.

Absorption is normally used above in order to control early arriving reflections just as they are on the side walls. The same purpose.

The collimating phase grating to which you refer - 'Space Couplers" - are used in a different manner; leveraging a loosely coupled space above the panels to provide a later arriving diffuse tail.

Practical issues determine their suitability, such as the energy return from the grating - as the return gain level must be sufficiently low enough (20 dB SPL down from the direct signal gain) so that the return energy is not destructive.

Thus their use as clouds is normally limited to used as clouds in taller rooms with sufficient 'waste space' above the gratings to be effective in providing a later arriving diffuse sound-field while, at the same time, also NOT causing early arriving reflections greater than 20 dB SPL below the direct signal level.

Bottomline: In a small room with 8-9 foot ceilings, go with a 4" thick absorptive panel gapped 4" from the ceiling.

[audiothings]

1. For the absorption panels in my vocal booth. Will 2" suffice, because the voice doesn't produce low enough frequencies? Or is a 4" a better choice?

The lower human voices go down to about 80 Hz. 2" of OC703 will not be of much use in that range, although it will have some effect in the upper registers and overtones. 4", preferably with a little spacing behind will serve you better.

2. Could I use this for aid around an vocal recording area? It would be nice have the portability. Your thoughts... click here for link.

strangely, I could find no information on the depth of the panel or any sound absorption coefficients, so its impossible to tell.

3. What is the purpose of hanging diffusers like these above the console from the ceiling? I see it sometimes in studio?

The page you linked to says that it "offers an attractive alternative to traditional absorptive and diffusive surface treatments"...

Is it because the ceiling is so high they need diffusers instead of a cloud type setup? click here for link.

It depends on the overall acoustical plan and particular implementation. In general they are supposed to allow for a more spacious sound... particularly useful in smaller spaces which happen to provide some otherwise unusable but available space in one or more dimensions.

EDIT: SAC beat me to it and will probably soon give me a virtual beating for it, anyway

[Jens Eklund]

http://www.gearslutz.com/board/6280707-post37.html
http://www.gearslutz.com/board/6505260-post2.html

http://www.gearslutz.com/board/5853315-post11.html

[ThePrez]

strangely, I could find no information on the depth of the panel or any sound absorption coefficients, so its impossible to tell.

Thanks for the input everyone. Here is what that site says on the material...

"Sound-absorbing 22"W panels have fiberglass-wrapped cores with tackable, cleanable polyester fabric surfaces for display."

Not sure on the exact depth, but just figured I could cover in material if I need extra padding.

[SAC]

You are considering paying ~$1000 for only 5 of those panels???????????? tutt

You can get the materials for ~$150 for 6 - 4 inch thick sheets of OC703!

And all it takes is butt jointed 3/4" x4" pine with unbleached muslin or your choice of fabric staples over them!

It doesn't get any easier!

You can of course do what you like, but typically such pod dividers are NOT simply semi-rigid fiberglass and also have a stiffener center - otherwise people would be putting them hands and chairs through them routinely, and having messed with too many of those things, you can't punch your way through them!

Oh, and what do you mean by "cover(ing) them if you need extra padding"? I hope you are not considering spending that kind of money and then essentially adding additional semi-rigid panels to the outside and then trying to wrap fabric around and stapling it to a 2" metal frame! Oh, that would look Nice! (And that's after you figure out how to get the staples to penetrate the metal frame and end up with what looks like a pillow top mattress cover or Tweedle-Dee and Tweedle-Dum as they prepared for battle!!)

I would DIY them, end up with much more effective panels, and pocket the substantial savings.

Wow, the flatlanders can't but be happy with this one, as we didn't make reference to 'a k u s t i k s' once in the acoustics forum!

[Eli Resnick]

Having temped, I would probably find myself unable to give a strong musical performance in the presence of cubicles.

Too many bad memories of boredom and wasted time. If you want me to make xerox copies of something, sure, put up those dividers. I'll have all your copies back to you in twenty minutes, collated and stapled.

Home-made clouds, on the other hand, say, "this is your time to shine."

SAC, To be more fair to the OP, I'm going to assume he's posting the link for visual reference, and is actually thinking about using used room dividers that an office somewhere is getting rid of. But I still wouldn't sing my best around them. If you get those ugly pink prison cells of conformity, you'd better get some kids in to graffiti the (*&*( out of them before you try using them for music. Unless you're going for a studio with some sort of Dilbert/Office space theme...?

Maybe keep a few old printers around for smashing, too.