*Home Vocal Booth - DIY vs. Manufactured

[partyofone]

Cool thread and some good info here already... I spent many a month studying acoustics.. bought a couple books on it and finally ended up building my own broadband absorbers. Instead of the common 703/706 I went with mineral wool which is MUCH cheaper and specs nearly identical if you look at all the brands.It's true that below 125Hz it's not super effective but if you go to the RealTraps page they have some interesting stats on effectiveness below this freq. And YES the thicker you can make it the better to a point.I actually built some Helmholtz resonantors to target specific low frequencies which the wool wouldn't be as effective at. The problem with Helmholtaz resonantors is that you have to tune them to a certain center freq. I was able to build about 10 broadband traps and 4 Helmholtz for a few hundred dollars. I wrapped my broadbands in muslin fabric but you if you have some extra dough those GIK or ones Mazz mentioned are reasonable.. plus it SUCKS cutting mineral wool or fiberglass!! I'm no carpenter so it took me and wife a couple weeks.I'd recommend the book "Small Budget Recording Studio From Scratch" for some great, low cast DIY methods.Lastly, I'd recommend using an omni mic and measuring your room. I downloaded a free copy of ETF back when there was a free version. I never got my room flat but got it much more under control.http://www.etfacoustic.com/

[southpaw]

Patrick, is there a reason you used the muslin fabric over a different kind? Just wondering.. That Guilford of Main stuff that people recomend is crazy expensive!How about that acoustic cotton, (ultratouch, or otherwise) did you look into that as well... It seems to work from what ive read just as well, although hard to shape with, it seems safer to work with and better for the environment i hear.. Thanks!

[yammer107]

Mar 20, 2009, 3:06pm, chriscarter wrote:Unless you absolutely have to have something 100% portable, skip ALL of those products. Here's the problem with all of them: they block very little sound going out, block only reflections that hit the null of a cardiod mic (duh....) and do nothing to block reflections that enter the front of the mic (where a cardioid picks up most of it's sound).If you want a great solution, here's what you do: 1) Go to Ross or some other mega discount store and buy two queen or king-sized plain comforters (ie. duvet). 2) Bust out your sewing machine and stich them together to make one big huge comforter. Now sew little loops along the top edge. You'll need at least three.3) Go to the store and buy some little cup hooks and screw them into the ceiling in a "V" shape. The open part is where you will put the mic and the corner is where your back will be facing.4) Hang it up.5) Stand/sit with your back into the corner of your curtain with the mic in front of you pointing into the curtain. If you want it really dead, move into the corner. If you want it a little more live, move further out of the "V". When you are done tracking, take it down (takes 30 seconds to put up / take down).This will work way better than any of the products you mentioned with some extra benefits: 1) no comb filtering messing with the sound; 2) it will cost maybe $50. 3) doesn't mess with your sight lines; 4) faster to put up/take down.I now record all my vocals in the control room with this method. If you want to hear what it sound like, listen to "mexico" on the music page of my website. The lead vocals were recorded this way with the vocalist about 18" off the mic. His vocal is dry with only a ton of compression so you can hear how effective this method is.BTW - it will also help cut out other noise (computer fans, etc.)I find this intresting ..... I did something similair with 2 x 4 stips of absorbtion foam ( the V notch pattern stuff) But I wraped it around the back of my mic ...... where your wrapping it around yourself and placing the mic in the open end. I was really just trying to stop some outside noise..... I mention this because I think I get a more open vocal sound without it .... maybe I've been positioned wrong all along.... Chri

[chriscarter]

Mar 30, 2009, 4:34pm, yammer107 wrote:I find this intresting ..... I did something similair with 2 x 4 stips of absorbtion foam ( the V notch pattern stuff) But I wraped it around the back of my mic ...... where your wrapping it around yourself and placing the mic in the open end. I was really just trying to stop some outside noise..... I mention this because I think I get a more open vocal sound without it .... maybe I've been positioned wrong all along.... Chri You CAN get a more open vocal sound without your device. This is the main problem with the Reflection Filter and similar devices - you get this comb-filtering of your voice because SOME amount of your voice wILL reflect off it back into the REAR of the mic no matter what. Let's see here, sound from your voice travels an extra foot for a 1ms delay and arrives at the BACK of the mic - OUT OF PHASE. That's can't be good folks....Here's the thing: cardioid mics ALREADY reject sound from the back of the mic. So why on earth would you try and block the back of the mic where it is already efficient at rejecting sound? At the same time, your voice (relatively omni-directional) is going out into the whole room, bouncing off the walls, and there is NOTHING to prevent those reflections from going into the FRONT of the mic where it's DESIGNED to pick up sound?!?!!??!!??!! The proper way to do is is to put the absorption in FRONT of the mic, which means it must go BEHIND you (otherwise, your voice has to go through it to hit the mic). So now your voice goes out into the room. It bounces off at least one surface. It may hit the back of the mic, but who cares as the mic is already rejecting most sound there - and even if it does, at least it's arrives 10 - 40ms later (depends on size of your room and location of mic), not 1ms (!!!). Now, that reflection must pass THROUGH your curtain you've hung behind you. Now it must bounce off the wall behind the curtain and then pass THROUGH the curtain AGAIN before it can hit the front of the mic where a mic is designed to pick up sound. See why this is so much more effective? AND it doesn't color the sound one freakin' bit. AND it doesn't get in the way of sight lines. AND it's cheaper.This method will beat the snot out of any of those expensive contraptions that go behind the mic any and every day of the week for sound quality. Now if you want portability, that's another story...

[ciskokidd]

Chris,Your post makes perfect sense to me. Thanks for taking the time to post this and to explain the sound principles behind the idea.Jamie, you really don't have much to lose by trying this out. I've already gone out and gotten my materials. All I need now is to borrow a sewing machine!BTW - I usually go over to a friend's house to record vocals so this will be kinda nice to have for quick demos.Best,Cisko

[southpaw]

already in the works! Thanks Chris. I have thought about the theory you are presenting, and like cisko said, it just makes sense. Kind of a 'DUH'! moment i had... On another note i have decided to add some more treatment by building some absorbers/gobos and bass traps to flatten out the room a bit more. For those of you that have done this using rigid fiberglass or mineral/rock wool, what kind of material did you use to cover + construct with? Why did you choose that, if you dont mind as well...

[mojobone]

Yes, cardioid mics pick up more sound from the front, but the effect is not constant at all frequencies. The theory behind these reflection filters is that sounds arriving at the back of the microphone will be more 'colored' (nonlinear) than sounds arriving at the front. This effect is known as off-axis coloration, and is often demonstrated by the following test: obtain a set of keys and a string, then with the mic mounted on a straight stand tie the key ring to the stand at a comfortable distance and walk around the mic jingling the keys while keeping the string taut and level and recording the results.None of the above posts has really made any distinction between good reflections and bad ones, either. Ever listen to a voice or an instrument in an anechoic chamber? It sounds very odd and unnatural, and generally nothing like what you want to hear in a recording. So some reflections are good; therefore, what we're attempting to do is control bad reflections. The whole operation is further complicated by the fact that some frequencies (below about 80Hz) can't be controlled at all, without the assistance of several yards of concrete.

[southpaw]

Thanks for making my 'blissfully simple' understanding of sonic reflection that much more complicated Mojo..... !

[yammer107]

[quote author=mojobone board=nick thread=12701 None of the above posts has really made any distinction between good reflections and bad ones, either. [/quote]Yes intresting again..... Guess its all about the ears and experimenting..... I was wrapping myself up because I thought it was the right thing to do... but upon listening realized I liked the sound of a slightly open room better.... but I'm in a fully finished basement; carpet, wood paneling & ceiling tiles. (my days of hanging carpet rements on the walls are over!) Chris

[southpaw]

Quote:Guess its all about the ears and experimenting..... I believe we all eventually guage our decisions on this as the bottom line.In the words of the great Ray Charles, "but what does it, sound like -baaby!?"Two things i've learned about recording and production discussions is that.. Things are almost never cut and dry... And It doesnt really even matter what the subject, their is always more to learn! ...got a little reading to do... Cheers.