Sound Proofing with Drywall?

See, my little brother is in college working with lasers to get himself a real job, but it's a lot of fun when our respective disciplines overlap, even if just a little bit.

He had to build a chamber that could reduce external vibrations for sensitive equipment inside, and asked me about acoustic treatments like foam. I of course go through my spiel about the difference between shaping reflections in a space, and absorbing sound, preventing it from leaking into or out of  a space. I then sent him some info on Owens Corning and like insulation.

He did some research on is own, and found a company that has developed an acoustic drywall. I hate it when the little bugger scoops me...

Billed as an alternative to mass loaded vinyl, QuietRock looks like it could be a good solution for those that have to use an existing structure. When paired with other treatments like insulation it looks like it can provide substantial attenuation across a wide spectrum of frequencies.

You can find more info at: http://www.quietrock.com/quietrock-drywall.html

Living Room Laboratory: The SM Pro Audio Mic Thing

While setting up a client's home recording kit, I got to play around with an SM Pro Audio Mic Thing. Similar in design to the sE Electronics Reflexion Filter, basically it's a foam covered screen that wraps around the back of the mic to help reduce room reflection and echoes.

I've always been a little wary of these types of products. When talking about "sound proofing", I often see people get caught up in the differences between treating a room for reflections and insulating a room. These types of screens are good at helping you shape a room (when used with additional room treatments), but are completely useless for insulating a room from outside noise.

My client had a small office (in a pretty quiet corner of the house) with hardwood floors for his recording space, so we decided to attack the space from multiple areas. We built PVC/Packing blanket baffles to "shape" the corners of  the room, we found a nasty shag style rug to throw on the floor, and employed the Mic Thing to finish the space off.

We decided on the MicThing over the Reflexion mostly because of price, being about $70 cheaper than the Reflexion. I don't think the build quality is quite as solid, but I do like that the Mic Thing is adjustable. You can take the screen's sides from perfectly flat to ninety degree angles forming a pretty tight box around the mic. One advantage of the adjustable sides is it makes it easier to use a music stand. We formed an "L" shape with the Mic Thing, the mic in the corner of the screen, and a concert music stand continuing on the flat end, so he could still read copy. I don't think this arrangement would be as easy with the Reflexion.

The SM Pro mic stand we ordered with the Mic Thing is formidable, and is easily one of the most rugged stands I've ever used. You can often find the two bundled for the same price as just the screen.

I like the Reflexion's Mic mount better. On the Reflexion the mic clip attaches from under the screen, and the depth (how far the mic is from the screen) is adjustable. With the SM Pro, the mic attaches to a boom that has to swing over the top of the screen. The closer the mic is to the screen, the higher the remainder of the boom swings up. It looks sloppy and is hard to adjust without swinging the mic around dangerously for minor adjustments. I think I'll recommend a two mic stand approach, one for the Mic Thing and a round base stand for the mic. I think this will make height and depth adjustments much easier and safer.

In all, I'm very pleased. We picked it to save a little cash, but it's doing the job well.

I had a chance to play with the Mic Thing in my living room, and decided to test it out with my M-Audio Solaris and a packing blanket baffle. I recorded first in Omni to get a sound for how "live" the room was, then added the Mic Thing, then switched over to Cardioid.

Take a listen with headphones to really hear the difference.

SM Pro Audio Mic Thing test:

Acoustic Cloaking Device to be Made From Crystals

Now you hear me...

So this is following up on the theories of cloaking objects from the visible light spectrum, that if you can get acoustic energy to flow AROUND a structure, then the inside of that structure is essentially acoustically neutral.

BBC News has the scoop:

Scientists have shown off the blueprint for an "acoustic cloak", which could make objects impervious to sound waves.

The technology, outlined in the New Journal of Physics, could be used to build sound-proof homes, advanced concert halls or stealth warships.

Darpa had a similar project running in 2007 to try and reduce acoustic energy from military vehicles, but I think this current project from Spanish researchers could prove more effective. It would also have more immediate consumer benefits (as well as more practical application for the Navy), though probably less effective for ground based vehicles.

Or maybe it would be too good. It might not be such a good idea to make a completely sound proof car...

Thanks for the link Jeff!

A post on Microphones, Sound Cards, and Sound Proofing

MICROPHONE!
Digging through some of the old equipment at one of the casting studios I work at (the oldest voice over casting studio in LA Woot!) I stumbled on a box of old microphones. Most were crap, but tucked away was an original capsule SM56! Had to tinker with the impedance, but got it set up, and it's now enjoying full time use. Near as I can tell, the mic is almost 40 years old!










SHURE SM57

SOUNDCARD!
I love Stumbleupon. It sucks so much of my life away, just stumbling round teh intarwebs.
Caught this Flickr pic from sneeka2 comparing the Firewire410 (my soundcard) to the Mac Mini. I was actually kinda surprised.

mini
Originally uploaded by sneeka2

I've been kinda disappointed in soundcards of late. Besides some of the Mixer/Interface hybrids, there's been depressingly little development. Is there anything you readers are looking forward to? Let me know!

M-AUDIO NRV10


SOUND PROOFING!
For those of you trying to set up your own recording booths, check out this vid from the Revision3 Gazette, and you can see what they went through to reduce echo in their studios. Now obviously this is reinforcement on an industrial level, but the lessons here are still valid for us closet junkies.


someaudioguy some audio guy voice over demo production voice acting adr dubbing animation anime narration

Audio Guy mail bag: Booth for home recording?

Just got this email in:

Hey,
Should I be worried about setting up a booth? Most of what I do is auditioning from home, but I do get the occasional gig which would be nice to do too.
-J.S.

Thanks J. I get this question quite a bit. Should you be "worried"? No. Should you be considering it? Yes. But with anything else we do, you really need to be honest with yourself over what you want versus what you need.

If you were recording promos and trailers every day, then you would be making the kind of income where devoting a whole room of your house, and getting an ISDN, and hiring a part time engineer (like ... me for example) would make sense. If most of what you're doing is auditioning though, then I don't think a booth is the way to go.

Would it help? Sure.

Enough to warrant the building cost and support? Probably not.

Most people at this stage of the game are much better served by taking a few simple (and cheap) precautions to ensure your recordings are as clean as possible.

Really, it's about knowing your equipment.
Most microphones are directional to some degree. Meaning, they should only pick up sound from a specific side or "face" of the mic. Most vocal mics are cardioid mics (cardioid ... cardiac, heart? Get it?), and they will have a subtle fan or "heart" shape recording pattern on one side of the mic. The other side of the mic will be dead.
Generally speaking, as long as the room you're in is fairly quiet (fairly closed off from the rest of the house), then you should be able to reduce reflection by treating just one or two walls or a corner of the room.

When you have flat hard walls in a room, and you're trying to record, the sound is bouncing all around. So, when you speak, the sound of your voice travels all the way across the room, bounces off a wall, travels all the way back to the wall behind you, bounces off that wall, and goes back into the mic AGAIN. Of course, that bouncing delays the sound going back into the mic, so you get a slight echo or reverberation ("reverb") effect. Now a little room tone is good. It gives the listener a sense of perspective, but hard surface reflection is often the first sign of an amateur recording (kinda like taking your headshots with a disposable camera).

So how do you fix it?

Well there are two main schools of thought on that. You can either try to block your voice from reflecting on the far wall, or you can block the reflection from the wall behind you. Ideally you would want to do both.
I find it's easier to hang a nice heavy blanket or rug, and record with your back to that. It works best if you can set it up in a corner, and make a little "blanket bowl" to catch reflected sound.
There are contraptions that can bolt on to mic stands that should absorb some of your voice's reflections, but they can be a little pricey, and I think some of them are a little too small to block ceiling and floor reflections. They also wont solve the problem of a hard surface behind you. Ideally, again, you'd want something behind you AND behind the mic, but I don't really think that's always necessary.
Keep the mic as far from your computer as you can (and try to point the "dead" end towards it), and if you have hardwood floors, it's time to throw a rug down.

Steps like these will work wonders for beginning home recording, and are easy and inexpensive to set up. As you become more successful, THEN you can look at the cost of building a room, or plunking down on a pre-fab Whisper Room type thing (the tinniest starting at almost $3000, whew!).

If you want something modular (that you can put up and take down easily) check out this PVC pipe project from PalmCityStudios.

Here's an article from a Wired blog about a professional marimba player, and what she had to go through to sound proof her NY apartment.

And lastly, heres a great Sound on Sound article about (not) setting up a booth.

Enjoy!