NEED HELP! Question on "true" benefits of sound proofing with double dry wall w/....

[HDTVFREAK]

green glue added. I am building a 35 X 15 ft HT room and my budget is getting thin with the house and we might need to "cut back" a few perks. I had my HT room budgeted for double drywall with green glue in between the drywall.

My question is...How much better does this make my HT room sound/perform?

This room will be in the basement and have two walls that are framed to the concrete block walls. I will have a 7.1 system with two sets of surrounds and a 12 inch sub. (SVS).

I know there of course will be a benefit to doing this, but how much? Is it worth it?

Thanks

 

[dronezero]

Well the purpose of green glue/double drywall is not to improve the sound of your theater, but to prevent the trasmission of sound between your theater and the exterior. So if you are not conscerned about the noise from your theater disturbing others and your not conscerned about noise from outside the theater disturbing your movie watching then I would say that you could skip it.

 

[bpape]

It's also a piece of keeping sound from the outside getting INTO the theater and raising the ambient noise level of the room thereby reducing apparent dynamic range. It's only a portion of the solution though. You also need to deal with any holes (electrical boxes, switches, lights), doors, and the air handling system. If you don't do all of those, then don't bother with the extra drywall and green glue as the others will defeat the purpose.

Bryan

 

[John Hile]

I read an article on this subject and to a certain degree, using Green Glue to damp your walls will improve interior room sound quality. There is a specific amount of sound energy that will hit the walls and reflect back into the room, but since Green Glue actually takes sound energy and converts it to heat energy, there is less sound energy reflecting back into the room. It's a nice place for your room to start.

Using double drywall and Green Glue will get you some high performing walls by preventing noise going either way, but as Bryan states (and he definitely knows his stuff) other flanking areas have to be addressed to make an isolation project work.

I would suggest getting the shell done properly and cutting back on some of your "Perks" in the way of electronics. You will always be able to upgrade your interior amenities, but you will get one chance to really make your room perform. Nothing would be worse than spending all that money on components only to be told to "Turn down".

John
___________

The Soundproofing Company

 

[bpape]

Agreed.

When you build it, use MDF boxes around all outlets and switches.

Route HVAC to go around the room. Bring it in via soffits which are built AFTER the room is drywalled.

Don't use tin duct, use flex. Tin can actually amplify noise transfer.

Use solid core door(s) on the room.

Plan on can lighting in the soffits, not direct holes cut in the ceiling.

Caulk all 90 degree butt joints in drywall. Caulk the bottoms of the walls to the floor.

Make sure you insulate fully above the room and all of the walls of the room.

THEN, you can do a 2nd layer of drywall with Green Glue to help noise transmission - especially in the bottom end.

If you're really serious, build the walls 1/2" short and tie them to the structure above with PAC DC-04 clips and use RSIC-1 and hat channel on the ceiling.

Bryan