Hello All,

Firstly a massive thanks to all, particularly Ethan. We're a music charity which works with young people in the most deprived borough in the UK and I posted a couple of years ago for assistance with a control room. I was advised to remove the vocal booth I had just built (ouch - pocket and pride hurt!) which I duly did, tested room, treated with Real Traps and got to within +- 5db below 300 with the help of you all.
Since then one of the albums we have mixed in the room has gone platinum!
It is now no longer a control room, but a live room and it's an exceptional live room, with a lovely sound and we have a much bigger control room which is fantastic too.
So thanks!!

To my new question and project!
We have secured funding to treat some rehearsal spaces. My builder has suggested using insulating laminates in the treatment see http://tinyurl.com/ltvbq9 I was wondering if anyone had an opinion on their effectiveness? The other alternatives being to make some traps from ethans designs, or buy real traps if we have enough cash.
Also we are trying to limit sound leakage. The wall to the next room is very very thick (1.5 ft ish) - like a castle wall. There is currently a fire door in it. I was thinking of adding a seal to the door and then putting a second door in as well. Is there a more effective way of minimising leakage, like a special door?
Also sound comes out through sky lights, which we will put 2 panels of double glazing with several inch gaps between in front of.
Many thanks for looking and your time and advice.
Regards
Gawain

Polystyrene is absolutley useless for sound absortion,not too sure about Phenolic.

audiofreek has the right answer - that laminate stuff is for thermal insulation only, not acoustics. As for sealing your door, that can only help. But the next weakest link will then take over. A door that isolates 100 dB is useless if sound can go through the walls. The solution for windows (and skylights) is mass, and plenty of it.

--Ethan

Thanks both, that's very helpful. So thick glass is the way to go rather than double glazing?
Gawain

I'm not a glass expert. I'm pretty sure Rod Gervais' book discusses this:

Home Recording Studio: Build it Like the Pros

--Ethan

It's best to have laminated glass of two different thicknesses to create this thick glass.Usually the layer between the glass is a poly-vinyl.Each pane,control,and live room side,would also be different thicknesses to prevent similar resonant frequencies.
Then when you create the splayed window between the control room and the live room,you need to create separate isolated casings for each outer wall to have good vibration isolation.
If your walls are not decoupled(room within a room)there is still some benefit in keeping the two sheets of laminated glass decoupled.You can do this by seating the glass in a neoprene strip.This can be taped on to the glass prior to putting the casings together.The splay should be about 15:1.Remember to mount the casing with the angle up.