green glue/resilient channel low freq question

[knapus]

here is a quote from the green glue web page under FAQ's:

"11. Can Green Glue be used in conjunction with decoupling techniques?

Yes, and better performance can be had. For walls the preferred decoupling methods are double studs > staggered studs > modern sound clips > resilient channel. For applications where low frequency isolation is important, resilient channel is not recommended."


now, I am building a version of the room within a room in my garage as a live/tracking room and am concerned with isolation, as broadband as I can get (close neighbors). Am I misreading this answer or are they saying that I would do better to skip the resilient channel and just screw the sheetrock/green glue sandwich to the studs? I refer to the point about low frequency transmission, which, as I understand it, is the real pain in isolation construction.

[stuntbutt]

If you are building a room inside a room then your inner frame is already decoupled from the outer frame. I don't think there is any benefit to using resilient channel on an independent frame.

[norton]

You can compare the STC ratings of walls on the greenglue website. They've got published results for pretty much every combination under the sun.

Also John and Ted at www.thesoundproofingcompany.com have a TON of information on their site...and in their collective heads.

In your present garage situaion... You'll have a really tough time getting any more iso than you'll get with GG whisper clips and r-channel. The variables after that become the thickness of the sheetrock on the sandwiches, the type of sealant you use for the seams etc.. and how well you seal it up.

Also you should really consider how much floor-space your walls are going to eat up. Some clips will push your wall out 3"... The whisper clip is the best one I've found for low profile, high performance and price.

Also, you've got to keep the ceiling and doors in mind as well.

Treat the ceiling the same way and don't get side-tracked by $1,000.00 door seals. They're not necessary. You can build your own that will work just as well. You'll just have to step over a threshold and build the stops out to have a more substantial cover of the door itself. But do call John and Ted... they'll totally steer you in the right direction.

Good luck!

zack

[knapus]

thanks for the help and the info...

Just to clarify, I guess I was most concerned with a not completely isolated new room (some connection to the existing structure) and the statement: "For applications where low frequency isolation is important, resilient channel is not recommended."

As stuntbutt pointed out, a totally decoupled structure probably wouldn't need resilient channel. But what do they mean exactly about resilient channel not being recommended to isolate low frequencies. Do they mean ever? or in their particular clips/channel/gg/sheetrock example?

thanks norton, I will contact John and Ted.