planning to build a vocalbooth

[skodela]

Hi guys

I am planning to build a vocal booth to record voiceovers for my animation.

My plan is to build a 120cmx120cmx180cm box with compressed wood/MDF kind of material. It will be the inside box. I am also considering building another box approximately 5cm bigger than above to encase the inner box with a quilt seperating the two.

My question is does the box itself needs to avoid parellel walls or would it suffice to have the inner foam+quilt layers non parellel while having the hard materials parellel!

This booth is going into a backroom with no walls shared with neighbours, so noise coming from neighbours should be reasonably low.

Does the box idea above sound reasonable to more experienced guys here!

I am planning to use it for VO only for the time being.

Thanks
sreekant

[GABritton]

To answer your question vaguely, any paralell walls are less thaan desireable, no matter the size.

Now that being said, since it is a small space, you're probably not going to run into major problems with having paralell walls. I would make them non-paralell just because why not!! You're building it yourself from scratch, so why not.

[Innovations]

Usually for a VO booth of this size you make the walls really dead.

The only reason for the second layer of MDF with a fiberglass filled airspace is to keep outside sounds from getting in, since your speaking is not going to be loud enough to bother anybody outside. So if the outside world is really that quiet you might be able to go with a single layer. But once you start using really sensitive mics in a really quiet room you might be surprized at how noisy the outside world really is.

[RICK FITZPATRICK]

To answer your question vaguely, any paralell walls are less thaan desireable, no matter the size.

To what scientific principle do you base
this assumption on?

[knightfly]

"To what scientific principle do you base
this assumption on?" -

Flutter echo would be a good start...

However, I would be more concerned that you are building a small box that has two dimensions the same, and the third dimension exactly 1.5 x the other two - this will mean that any sounds NOT absorbed in the "box" will have MANY peaks/dips in level that are in the AUDIBLE range - it isn't possible to make this shape booth sound good, or even "not bad" - by the time you put enough absorbent material in there to make it usable, there would be no room for a PERSON.

In imperial units, this is a 4x4x6 foot box - you can improve the sound inside by leaps and bounds by changing the inside dimensions to 3x5x7 feet, which would be 91cm x 152 cm x 213 cm - this would feel MUCH less claustrophobic but just as important, it would take TONS less treatment to sound usable for VO or any other booth work.

Your idea for a second "Leaf" outside is fine, but a wider gap between the two will improve isolation especially at lower frequencies - don't use flammable blankets between leaves, however - this is where fiberglass or rockwool insulation goes... Steve

[RICK FITZPATRICK]

Flutter echo would be a good start...

Doggone it Steve....I KNEW you would say that. Hmmmmm, at the speed of sound, and walls 4 feet apart, that would be flutter echos at...................mmmmmmm lets see........ 0.0035398230088495575221238938053097 seconds apart .....oh hell, even I can hear that. Geeeeeeeezus. Can't sneak anything by Steve (just kidding!)
fitZ

[Innovations]

Just because you can't hear the individual echos does not mean that they aren't muddying up the sound.

Steve's right about the 5 foot dimension being better, but it is so much harder and more expensive to fabricate out of 4 foot material that I don't automatically recommend it. Most tiny booths are so deadened that the small room reverbs just don't get a chance to get going.

[RICK FITZPATRICK]

Just because you can't hear the individual echos does not mean that they aren't muddying up the sound.

Are you telling me that you can hear the difference on a recording or over the monitors Just by changing a wall angle within a four or five foot distance between them? Maybe so. But then again, ask all the people who have built them if they hear it Besides, didn't you see my......"just kidding"? I ALWAYS trust Steve. Its just in my nature to question EVERYTHING. Even if I make a fool of myself doing it. If I listened to every tom dik and harrys replys on this board, my studio would be built of blankets, eggrates, and celotex walls. Hmmmm.....where DID I put that stack of moving blankets?....I hear a train comin.
Ok Inno, I have one for YOU. What is the difference between a STANDING WAVE, and a MODE, and how are they related?
fitZ

[skodela]

Hi folks

I have been looking around for the materials and I found a decent thickness MDF [18mm] at B&Q. It is of 2440x1220 MM. Now I was considering the advice given earlier to make the sizes 3x5x7 ft.

What would be the ideal size of booth that can be made from above dimesions of MDF! I am basically looking to keep the amount of sound treatment needed to absolute minimum.

Any help greatly appreciated.

Thanks
sreekant

[DDev]

The MDF sheets you described are basically 8x4 feet, so to get the desired 3x5x7 feet you will need to do the following:

The 3x7 foot walls will require that you cut 300 mm off one side and 300 mm off the top.

The 5x7 foot walls will require that you cut 300 mm off the top and splice the 300 mm you cut off the long side of the 3x7 foot wall to one long side of this wall to make it wider than the stock width.

This will get you the wall dimensions you are after. I'll let Knightfly fill in the next set of details.

Good luck,
Darryl.....

[skodela]

Hi guys

I got the 18mm thick MDF delivered now.

I also saw the "loft insulation" in the DIY store. It seem to be some sort of fibrous insulation material, approx. 1cm in thickness. Would it suffice to use it inside the booth to deaden the place.

Thanks guys
sreekant