John Sayers' Recording Studio Design Forum

I have a vocalbooth.com booth in my apartment in Hollywood. I am trying to beef up for keeping sound out. The room is fairly quiet considering my location. I was thinking of ripping the 1" foam off, glueing down 1/8 vinyl, and then glueing my 2" and 3" foam on top of the vinyl. I also have bass traps so was wondering if I should put one or two in there as well. Is this a good solution? I want to keep the unit less bulky so I can move it easier when the time comes. I record VO only.
Thanks!

to increase the isolation you need mass - maybe consider adding a layer of MDF (walls and top) which you can un-screw later when you need to move it. the other consideration is the window and door - are they massive enough and sealed properly? on the added MDF layer, you may need to put another window frame on it to add more window mass and/or an air-spring gap (assuming the window is only single pane today. the door - same - maybe a layer of MDF screwed on. also, any ventilation openings need to be checked to determine if they are the source.

_________________
Glenn

I think that with the money you have already invested, you do not want to try to "re-invent the wheel" so to speak.


If it is a coupled wall assembly or even if it is the double wall, or maybe more importantly if it is a double wall, I would look into a few things before I started remodeling this booth.

One thing, first, I would see if the isolation is better if it were moved away from the wall. This could actually be an issue. But I think just as important, depending on the floor you may need to simply decouple this booth from your existing structure. Sound moves faster thru concrete and faster even more thru steel...but doesn't mind wood...but not to the same extent.

_________________
Brien Holcombe
_____________________________________________
Sound: You can't stop it, you can only try to contain it.

Thanks guys! It actually does a decent job of keeping the sound out. However, I just wanted to get the max out of it I could. It is a single wall construction. I am thinking a layer of MLV, and a layer of soundboard or MDF over that, and then the foam. I know the MDF is better however it is also very heavy. Thanks!

You are free to think all you like, but I refer you to my post above.....you have access to money ...but the access to the way to do this job eludes you or you really have no intention to consider that there is a good chance...you are not correct

_________________
Brien Holcombe
_____________________________________________
Sound: You can't stop it, you can only try to contain it.

Well, to be honest, "heavy" is the entire point!

It is impossible to get isolation without "heavy". There are no magical properties to MLV, soundboard, MDF or anything else, despite the marketing hype that you might see. What makes them all work is simply mass.

Mass is mass. Mass is what stops sound waves, not marketing hype. The sound waves really don't care how much you pay for the mass: all they do is stop when they run into sufficient mass. They don't give a damn what the mass is made out of, how much it cost, where you bought it, what color you paint it, or any other factor. If you have a single-leaf wall (which you do) then it is governed by the immutable law of physics known as "mass law", which states that you get a 6 dB increase in isolation each time you double the mass. The laws of physics also don't care how much you pay for your mass: all they care about is how many kilograms of mass you have, period. Not mass means no isolation. So if you don't want to increase the mass of your booth, then you cannot increase the isolation either. Simple physics.

That's just a long-winded way of saying that, if you want to increase your isolation, then what you need is more mass. And it doesn't matter what type of mass you use, so you might as well go for cheap mass. MLV is VERY expensive mass. Soundboard is expensive mass. MDF is cheap mass. 100 kg of MDF will stop the sound waves in the exact same manner as 100 kg of MLV, but the MDF will only cost you a fraction of what the MLV costs.


Bottom line? If you double the total mass that you have right now on your booth, you will get roughly 6 dB of extra isolation. In real terms, that is a noticeable decrease in volume, but subjectively you would not say that it reduces the volume by half. Subjectively, it would reduce the volume by about 40%.

That's the plain, simple truth: forget the market hype that the manufacturers of expensive products want to feed you, and just follow the plain old science of acoustics. What you need to do is to add mass, and since all these different forms mass are the same acoustically, you might as well go with MDF, which is cheap.

Unless you really like wasting money, in which case you could go for exotic mass, such as lead sheeting, or maybe silver, gold, platinum, titanium, .... kilogram for kilogram, All of them will get you the exact same results, in terms of isolation.


(PS. The foam won't do a thing for you: it's mass is insignificant, compared to the rest of the booth. It would only be useful if you had a proper decoupled MSM 2-leaf structure, but you said that this is single leaf, so the foam is pointless and worthless, acoustically)

(PPS. Like Gleen and Brien already said, you might well have other issues there, such as the position of the booth with regard to the walls (yes, that is important, and can change the isolation, for sure), or weak spots in the construction, such as the window, door, sealing, air vents, etc. You will probably get a much better boost in isolation by paying close attention to those, than you would from doubling the mass.)


- Stuart -

_________________
I want this studio to amaze people. "That'll do" doesn't amaze people.

Thanks everyone for your replys.

We are just kids at the candy store, noses pressed up against the glass

_________________
Brien Holcombe
_____________________________________________
Sound: You can't stop it, you can only try to contain it.