new vocal booth acoustic teatment help

i'm just finishing of the acoustics to my new studio,which John sayers gave me some fantastic help with last year . i have 4 rooms to treat but i am starting one at a time to get it right. i have contacted auralex and faxed my room size diagram and they came back with a suggested treatment plan for me .can anybody help at all with acoustics in vocal booths . i will be doing mainly vocals for songs radio voice over work and some ac guitar so the room needs to be dead but not suck the life from the mic or performer. i hve inclueded the room size which i drew and the pdf file Auralex sent me if you can look at this and tell if they are bang on or is there a cheaper option . thanks in advance for any replys . greeny in the U.k.

That's a decent size booth for vocals and guitar, but you should plan for substantial bass trapping as well as mid/high frequency absorption. The smaller the room, the worse the problems at bass frequencies. --Ethan