Voice over Booth Treatment Question

[wannaknow]

I want to check with the Guru's here to see if I'm on the right track treating a voice-over booth. The space is on the second floor of a commercial building. It's 2 meters wide, 4.1 meters long, 2.7 metres high. The 2 meter wall with the door is glass; the rear wall has a weird step up that's 1 meter high and 1 meter deep with a 3 sided window 1.7 meters high. I plan to put 2, 1200mm x 2400mm x 100mm panels on each long wall, and 2, 1000mm x 1000mm x 100mm movable panels in the window area, and suspend 1, 1200mm x 2400mm x 50mm panel from the ceiling, The glass wall and door will have either 50mm or 100mm thick panels. The panels will be made of with a product called Acoustisorb 2. I'll also make a panel to go behind the mic. Hope you can make sense of my crude diagram: My question is, does this make acoustic sense? "Quality voice-over is the primary consideration" There may be a ventilation issue, but that can be addressed separately. Any guidance will be greatly appreciated.

 

[allegro1650]

I've noticed one thing straight away.

Have you ever seen a room with mirrors on either side, and the visual reflections when you walk in make it seem like there's an entire line of people looking like you?
The same thing happens to sound. Parallel hard surfaces will reflect off each other, and create what's called "standing waves". (a handy link)
A metallic 'ping' kind of echo will occur with any sound in the room, but it will be particularly noticeable with hard transients like finger snaps and hand claps.
Certain low notes will build up and become boomy, depending on where one stands (or where equipment is placed).
That must be addressed in design and construction; absorbing panels will only do part of the job.

 

[Steenamaroo]

I've noticed one thing straight away.

Have you ever seen a room with mirrors on either side, and the visual reflections when you walk in make it seem like there's an entire line of people looking like you?
The same thing happens to sound.

Oh, that's just lovely!

 

[wannaknow]

I've noticed one thing straight away.

Have you ever seen a room with mirrors on either side, and the visual reflections when you walk in make it seem like there's an entire line of people looking like you?
The same thing happens to sound. Parallel hard surfaces will reflect off each other, and create what's called "standing waves". (a handy link)
A metallic 'ping' kind of echo will occur with any sound in the room, but it will be particularly noticeable with hard transients like finger snaps and hand claps.
Certain low notes will build up and become boomy, depending on where one stands (or where equipment is placed).
That must be addressed in design and construction; absorbing panels will only do part of the job.

I'm not sure I understand your main point. I know of someone that does professional voice-over work from their home. (I haven't seen their space) I'm pretty sure they don't have near the amount of treatment I'm proposing. My thinking is; I don't have to be overly concerned with low frequencies below 150hz / 200hz because there will only be spoken words. There will be an air gap behind the panels. There will be very little bare wall exposed.

 

[wannaknow]

Steenamaroo, I think I get your point.

 

[witzendoz]

I don't completely understand the diagram, I will give the thumbs up to Acoustisorb, are you buying it through Insulwest? Ask for Maurice he is the font of knowledge on this stuff.

My studio has Acoustisorb in the paneling, bass traps and even in the ceiling cavity, I banned any fibreglass in this build as I am sick of working with the stuff. If you are trying to keep outside noise out you may need Acoustisorb 3 and you will need to completely seal the room. Don't forget the floor and ceiling.

Alan.

 

[Bobbsy]

Like Witzendoz I don't fully understand your diagram but another positive response to Acoustisorb from me. I've used it in the past (usually the 100mm variant) for voice booths with good results.

The point about the glass is technically correct but, in the real world, almost every voice booth has a window, if only to the control room. You can get away with it. I prefer to keep the windows on the flank wall, i.e to the side of the speaker, not directly in front or behind.

At the risk of stating the obvious, for voice over work you want the room as acoustically dead as possible rather than worrying about making it sound "nice".

 

[Btyre2013]

looking at your room, that glass is going to cause serious problems acoustically

 

[wannaknow]

The step at the top of the diagram is a side view of what you would see from the door looking into the room. The other bit is a crude floor plan. I was reluctant to talk to the folks at Insulwest because I got the acoustisorb somewhere else. Yeah, I'm very concerned about the glass as well. Surprisingly, I don't detect any noise from outside the building. Thanks guys, I'll post how it turns out and how I handle the glass issue.