Rumor is there's an Acoustics forum here.

Just BTW. You could almost buy a vocal booth for the price that he built his.

http://www.whisperroom.com/

Given most of the "vocalists" one hears lately, perhaps making it airtight would be a nice feature.

Hey I built one

Hi I bulit a vocal booth similar to the one in your link, actually I used that site as a reference as well. I used 22mm MDF which in europe is Medium density fibre board. Particle board I understand as a slighty coarser material.Truth be told I can't really sing but it certainly gave me a lot more confidence to belt it out and know that the neighbours can't hear me..lol.I lined it with rockwool which is a building insulation material which is actually made from rocks! Here are some links that may be useful http://www.customaudiodesigns.co.uk/help.htm
This one I highly recommend: http://www.acoustics101.com/
I also lined it with sheet plastic to seal in the rock wool which i suspect is not very good to breath in and then covered that with nobbly foam rubber which i bought on ebay.I rekon i made it for a lot less than the guy in your link however I had access to a circular saw for cutting the MDf sheets which I must warn you are really heavy.Well all and all its was worth every penny as i can now play my guitar acoustic and electric and no-one can hear a thing. Anyhow i wish I could post some pictures on this forum but i suspect it wont let me.Anyhow if your interested in hearing the results check out http://www.mixposure.com/boneman and remember I'm a buck amateur and dont consider my self a singer.Anyhow good luck. :D

Is it a bad idea to have a window right behind the mic? wouldnt that create reflection? or does it matter with all that foam in there?

I doubt it would do any noticeable damage. The thing I would be curious about is that halogen light he has in there. That just screams fire hazard to me but I suppose the foam is flame retardant.

Window

Yeah i do have a window behind me and the mic in front that means I am between the mic and window but theres so much foam in there I doubt it makes a difference.As for a fire hazard I have flame retardent foam and I also have a strip light and a smoke alarm just in case.Shouldnt be a problem with halogen either just be senseable. :wink: