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Old 17th November 2009
Here for the gear

Thanks a lot for your answer!!
This was the constructive feedback I was looking for!

Originally Posted by jhbrandt View Post
ok that IS tiny... only 22 cubic meters. ALMOST a cube.. but, luckily, not quite. heh You will have modal issues - but you probably already knew that. Right around 100 Hz.
Yeah, 100Hz up to around 500 Hz is pretty terrible at the moment.
The only type of "absorption I got in the room now, is molton on the walls, heh.

Are you doing surround mixing?? 5.1?? etc.
Luckily I am not doing any surround at the moment.
The producers have been talking about it, but I've told them that, if so, I will need a new, much bigger room, and lots of $ to treat it (and lots of gear )

Well, first of all: You are wasting space and material with all that and not building an effective soundproof partition.

Give yourself some room in there.. it's tiny.. don't make it too much smaller.

1. Use steel studs. They are much better with transmission loss than wood.
2. Place your bottom plate leaving at least a 4" air space from the existing wall. -- this is what really does the isolation.
3. Rock wool between the steel studs.
4. 2 layers of 5/8" gypsum board sandwiched together with Green Glue.
5. You will need to install another door on the inside wall.
This was sort of what I was planning to do, kind of.
I was planning on a 2" gap from the old wall, but I'll make it 4" now.
How thick should the new wall/insulation be? I was thinking of 2", but should I make that 4" too? What kind of rock wool is the most effective here?
I've read that putting a layer of asphalt-sheets between the layers of gypsum is effective. Is this true, or just a waste of money? (they are expensive).
I'll have to try to find green glue here in Norway. If anyone know, a hint would be great!

Room Treatment:

Basically, you will need to put some good bass traps in every corner, good broadband absorbers at all reflection points, eliminate flutter by checker-boarding absorbers on walls and ceiling so that opposing surfaces are not both reflective.
The production company bought (before I started working here in august) a whole bunch of Ecophon Wall Panel™ A/Texona, 40mm. The sales rep told them that covering the walls and ceiling with this would be a perfect solution. Well, looking at the sound absorption coefficient chart, the absorption drops dramaticly at 500Hz and below, so no bass trapping. Kind of makes sense with the 40mm depth.
Well, the producer will probably kill me if I don't use any of the 103 m2 they bought of this stuff (I think they are planning on using it in edit suites too).
So.. would it be an idea to cover the walls and ceiling with it, and then put bass traps in corners and on the back wall? Or, will this make the room too dead?

NOTE: If the ceiling is dropped, look up there - and check that the existing walls go all the way to the next floor or roof. IF THEY DO NOT - You must extend them to the roof or next floor (and seal them well), otherwise all your efforts to sound proof will be wasted.
The room is built as a series of rooms inside a huge studio. So the walls go up to the ceiling (of the room, not the studio hall). There are two ac ducts in the ceiling, should i seal these? We have turned this AC off for my room anyway, as it is way too noisy.

Speaking of AC. I am now using a Multi Split AC System. The fan part which is inside the room, is kind of noise (pretty much the noise of air blowing). Do anyone have tips on how to make this silent? Connecting to the house AC is possible, but it is noisy as hell. Yeah.. we have huge problems with it recording in the studios.

Thanks again John! I appreciate it!
You are making my day a whole lot better!