Price/performance ratios of resilient bar etc...

[Deluks]

Hi guys, I'm in the planning stages of building a 10ftx12ft rehearsal room in my garage at the end of the garden, (approx 50 ft from nearest house) and I need advice as to which soundproofing treatments to go for within my budget (very small!)

Does anyone know of a price/performance ratio for various treatments?

The garage is 16x20 feet with the jam room to be built as a stud partition against one of the 20 ft walls. I intended to use 4x2 base and toplates, with a couple of layers of half inch plasterboard (drywall?) on each side, filled with 60mm rockwool (like I said I'm on a budget and can't stretch to 100mm)

After doing research I'd anticipated resilient bar (RC?) on the inner walls, with acoustic membrane (rubber sheet) sandwiched between the 2 inner layers of drywall but after adding up the costs I had a shock

At what point does drywall alone stop being effective? Cos it would be cheaper to drop the RC and membrane in favour of an extra layer of drywall on the inside. Would this be as effective, or will RC and /or membrane be provide that much better performance? (I'll be having drums, bass, guitar, vox in that room!)

The floor of the garage is concrete so I've already been sold on the idea of using neoprene strips to decouple the structure. Incidentally would I need neoprene all the way round the bottom? (Could I not just cover half the base with it and fill the gaps with some cheaper material?)
I also have no idea where to get the stuff from here in the UK!

Thanks in advance for any help, I hope my questions were easy to understand.

[Innovations]

You can go to the USG website and look up the STC of various assemblies, then price them out.

What you want is mass-air-decoupled mass. It really doesn't matter what kind of material makes up the mass, although construction details (caulking joints, no penetrations, etc) make a difference. In other words an extra layer of drywall is cheaper and just as good as that layer of mass loaded vinyl. However subsitituting a layer of drywall for the resillient channel would not in a single stud wall because then the second leaf would not be decoupled. However in a double stud wall you could substitute another layer of drywall for the channel because the two leaves are already decoupled.

[Deluks]

Originally Posted by Innovations

in a double stud wall you could substitute another layer of drywall for the channel because the two leaves are already decoupled.

Aha! I'm learning more all the time

So if I junked the RC idea, and went with double stud wall (probably with 1 drywall & 1 18mm MDF on the outside, and 2 drywall and 1 MDF on the inside) will I need seperate top and soleplates? Would I lose a lot of soundproofing if I used a single 2x6 for the floor/top, with staggered 2x3s as studs?

...or in this instance would I be better of with 2x4 top and soleplates, using only 2 layers on each side WITH the RC?

It's a minefield of options!