I have just Skimmed through Rod Gervais's Home Recording Studio Book and would like feedback regarding a size for a booth for just recording voice, since this is what it will be used for.The info Rod has in the book is awesome by the way!!! TJ
Here is the deal, the smaller the room, the more you will have to treat it with absorbing material, which will suck up the "air" in vocals. In my experience booths smaller than 4'x6' sound not good, after this it's getting better.
I find booths more suitable for radio announcers, voice over type of applications, not for music.
If there is incoming or outgoing noise problem then you will most likely need a booth, otherwise you can treat your existing room.
Are you wanting to build a 'vocal booth' to keep extraneous noises out of the vocal mic, or to keep the sound of the vocals 'in' (i.e., to keep from disturbing housemates or family in a 'residential' home studio setup)?
In most cases the small room dimensions of something the size of a 'booth' will do more harm than good, and you'll be fighting acoustics to keep from having an unnatural 'boxy' sound. If you're doing something like tracking a live rock band in a live room and a vocalist at the same time in a vocal booth, the tradeoff can be worthwhile in the interest of isolation, but in pretty much any other situation other than 'multitracking things live that you want to try for separation on', I'd say a 'vocal booth' is a waste of time, money, and space. If you're trying to keep other noises out of the mic, or improve the acoustic tracking environment, ideally it would be better to treat the noise and/or acoustic problems so they benefit the 'whole room' - get a 'silence case' for your computer or recording device (or designate a ventilated closet or adjacent room as a 'machine room' to get anything with a motor / fan / drive out of your tracking/mixing/listening environment), improve the acoustics of the room with treatments such as broadband absorbers or 'bass traps', such as RealTraps (or the ubiquituous homemade 703/705 panels everybody's putting in their home studios these days), so that the improvements benefit your whole space and tracking-mixing workflow, and not just one little 'booth'.
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