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Recommendations for acoustic barrier

"Deployed environment?" You mean like from a remote location, like a mall or store?

Or do you need to cut down echo in a studio environment?

I suppose the big folding panels would help, especially if you are doing a long remote from an inherently noisy location like the center court of a mall.

If you are trying to quiet down a more permanent location for a studio or an interview room I would look at the various soundproofing materials from this company:

http://www.acousticsfirst.com

We built studios in what were the bedrooms of a split-level house, what became the production studio faces out onto a busy highway (one of the factors that led us to buy the location--the main ones being an easy STL shot, the owners wanted to sell & we had only two months to move from the old studio location...)

In the control room we used the "Respond" fiber glass panels to break up the sheet rock walls & glued sound proofing foam into the corner of the master bedroom where the console was installed.
In the production studio we interspersed the four inch wedge foam pieces with the fiber glass panels on three walls & part of the fourth, which dampened down outside noise considerably.

One consideration is flame retardant characteristics of the sound proofing materials, especially in permanent installations.
 
The title of the thread seem to have some dissonance, some dischord in the wording of the title. As our friends in the "house of worship" world have developed larger groups than was typical in previous years, and as they add news styles of music that are more demanding of their space, accoustics has become a big, big topic. If the acoustics of your "space" are bad, you cant come up with a sound system big enought and bad enough to solve the problem.

In discussion that I follow in that universe, I often see discussions where people are confusing teminology from two disciplines. The word "barrier" gives the indication you are want isolation, separating good desireable sound from ambient noise. And language in the context of the thread. That is a little different than acoustics. Barrier indicates yu want to keep different sound source in their own place.

Minimizing echo gives the indication you want acoustical conditoning of an area for recording or live broadcasting that gives a pleasant sound, maybe voice qualities of maximum inteligibility.

Isolation barriers and acoustics are two distinct skills or discipines. In broadcasting and recording we often want some of both.


Define for us what you want us to help you with.
 
Try the Crown CM311A head-worn microphone if you want isolation. I use them in live sound to achieve higher gain-before-feedback. I have one on my ham station with a gate to reduce the blower noise in the room from the power amplifier getting into the mic.
 
TomT said:
"Deployed environment?" You mean like from a remote location, like a mall or store
Click to expand...

Sorry, I mean Afghanistan.

And I guess I was a bit too vague in the description. My mission is to be able to record news from a plywood shack with the least amount of undesirable audio as possible, and to do so in as little space as possible. Portability is key. We've got mics issued to us, it's just the blasted echo that I understand we're having a problem with.
 
There are lots of portable acoustic options that would help, but they're expensive and will take time to get. In the meantime, hang blankets if nothing else. Try to avoid going straight at the wall so that any reflected sound bounces away from the mic. Better insulation would yield better results. Either solution would improve a plywood box, but neither one will isolate you from sound bouncing off the wall behind you, the floor, and the ceiling.

First thing I'd try is grabbing some mike stands with booms, hanging folded blankets off them, and facing a corner. Create a "blanket booth". The results may be acceptable. Ultimately, insulating your plywood box & adding fabric between you & the insulation would work wonders.
 
Here's the mike that the BBC helped develop for live recording of commentary in a high-noise environment:

http://www.bhphotovideo.com/c/product/356414-REG/Coles_Microphones_4104B_4104B_Lip_Microphone.html

It works similarly to the Crown mike/headset combo. Of course, if you've already been issued something else..... ::) .
I'd recommend the blankets-hung-from-something system for acoustical issues. As for noise, all you can do is work really close to the mike.
(Or, use the Greatful Dead "Differential Mike" method, which is using two identical mikes, wired out-of-phase, and offset physically by just a tiny bit. That's basically what these "lip microphones" are. You keep your lips right up close...closer to one than the other....and the voice comes thru. The ambient noise, though, hits both microphones simultaneously, and cancels out. That's how the famous Greatful Dead sound system was able to overcome feedback.)
 
SirRoxalot said:
I'm not sure how well a ribbon mic would hold up in Afghanistan...
Click to expand...

The BBC has been using the Coles mic in combat conditions for many years. The big problem is it is really expensive. On the other hand, it is a lot easier to carry around than a sound booth ;)
 
I made a cheap, effective barrier with three sheets of plywood, some hinges and nuts, bolts and washers, FIRE RATED packing foam (comes in 4' x 8' sheets) and a tube of Liquid Nails.

Putting it together should be obvious.
 
Any time you have a small space with parallel walls you will hear a peaking "echo" with a certain pitch.
It is sometimes noticable easily in narrow stairways and seems like a ringing effect.
It is caused by a standing wave formed when waves reflect and breaking up the parallels somehow is as
helpful as adding sound absorbing material. That is why many acoustic foams have the wedge baffles.
These send refelections into diffusion. A small box is really going to be the worst for this.
Closer miking means less gain is needed, and a processor with noise gating can overcomie a small amount of echo.
You haven't mentioned at all whether you're live or recording. If you can play with AGC settings try them ALL...

Mentioning differential miking reminds me of another method, bringing the mike element very close to a wall, floor, or other surfaces which is actually part of the reasonant/echo thing. By adjusting the distance, it is often possible to find a
short spacing which cancels ambient noise; the undesired sound simply "isn't" there in that spot.
It can be very helpful in a classroom lecture or live music miking.
You'll need to wear good full quieting headphones and monitor while setting this up, and it can't be at all variable.
Sometimes you can get a good clean cancel off something as small as a 12" by 12" album cover or piece of wood.
The surface of that object from hard and shiny to soft and fuzzy will also determine the final sound. Good luck.
 
TomZ said:
Crown developed that short spacing technique down to less than an eighth of an inch.
Click to expand...

Keep in mind that this cancellation process will actually be a comb filter, with the frequency of cancellations relating to physical wavelength of the distance between the two mics.

In other words, as with any comb filtering, it can sound pretty odd under some circumstances of misuse. A few of the vocals on those Grateful Dead live recordings sound pretty nasal, for example.

Kind Regards,
David
 
kenglish said:
(Or, use the Greatful Dead "Differential Mike" method, which is using two identical mikes, wired out-of-phase, and offset physically by just a tiny bit. That's basically what these "lip microphones" are. You keep your lips right up close...closer to one than the other....and the voice comes thru. The ambient noise, though, hits both microphones simultaneously, and cancels out. That's how the famous Greatful Dead sound system was able to overcome feedback.)
Click to expand...

That's very interesting, and if what you say does work, we would have that capability with multiple microphones available for use.
 
Tom Wells said:
You haven't mentioned at all whether you're live or recording. If you can play with AGC settings try them ALL...
Click to expand...

Recording exclusively... directly to a Panasonic P2 camera. The drawback is that the 2 mic inputs are recorded on separate channels, so I'm unsure this technique would work after rip and mixdown. However, we do have the option of toying with the audio in Adobe Premiere CS 5.

Your recommendations are outstanding and with the right technical expertise, would save Uncle Sam $$ and of course everyone wants to do that these days.

Thanks ever so much. :)
 
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