Questions on Basement Design | John Sayers’ Recording Studio Design Forum archive

So, I’ve been going over the Gervais “Home Recording Studio - Build it like the Pros” book and lurking around on this site as well as others. I think I’m finally ready to take a crack at building a studio in my basement. I own a 1924 craftsman, and I’ve drawn out the existing basement structure in Sketch Up. The green area is the area that is “ available” for building out the studio (and a hall to connect it to the stairs). The red framing is my initial plan for layout. I know the framing is messily rendered (for one I will probably switch it to 24 on center). But it gives an idea of the general layout. Plumbing and duct work aren’t pictured, basically there are a few ducts and pipes that go between the joists above the proposed studio area. I am working on drawing those in. I have about 10k budgeted for this project. So not a ton of money. 1.5k probably has to go into updating some the plumbing that would get covered up with drywall. Another 3k would go into putting an egress window in. So money is going quick. I have a general contractor friend who is willing to give me some very low prices on framing assistance, etc. So maybe around 4-5k for materials. Not a ton of details as far as funds go, but it is a start. Important factors I’m considering: I'm going for a single tracking/mixing room. The studio will be for my own solo projects. Mostly mixing with some acoustic instrument recording. Let’s say 20% recording 80% mixing. Maximum isolation of noise coming into the room would be ideal as I would like to have the ability to do more delicate recordings and mixes. There are three sources of outside sound getting into the space. They were measured using a meter app on my droid smartphone. I figure that is not the best equipment, but perhaps it is good enough? At its quietest moments the meter hangs out around 35db. -I live on a kind of busy street. You can hear passing cars in the basement. 50db - may get louder when a really loud truck goes by. (also, a fair amount of this may be coming through the floor from above) -At the moment there is not drywall/insulation on the joists and I can hear every footstep upstairs. We have fir floors with a subfloor. Lots of low end thump - not sure how well the meter registers that. Feet are loud. 67db measurement. -The furnace makes noise when the fan kicks on. 68db measurement. I’m wanting to replace the existing window with an egress window (not pictured) because I’m not sure how many more years I’ll live here, and it would be great to have this double as a bedroom for resale. Not to mention, I want the light. So this might be the weak link. Even if get a special miller quietline window with a STC rating of 44 and build a plug for it. Here are two different very basically framed versions for initial feedback. Links are to sketchup drawings basement_mock_3 has the frame straddling the beam for a room width of about 10’ 7”. https://dl.dropboxusercontent.com/u/23176433/basement_mock_3.skp basement_mock_2 has the frame moving past the beam for a room width of about 13’. https://dl.dropboxusercontent.com/u/23176433/basement_mock_2.skp I know if I do this I would have to frame around the posts and the beam (not pictured). Which would be unsightly, and add a lot of funny framing, not to mention it might require moving some of the existing ducting. But…it might be worth the extra room…the other version seems like it would feel tight. Maybe I could get creative and build some recessed shelves in. My main questions are… If I go with an egress window - is it worth bumping up to 2-3 layers of drywall against the foundation? Are those footfalls every really going to go away? (I’ve seen Rod’s three layers of gypsum between the joists, then insulation then an additional three layers of gypsum- seems expensive, but probably necessary). Is my budget even close to covering the costs to create a pretty quiet space? Or should I just do minimal sound proofing/treatment, forget about ever blocking out the foot falls from upstairs, skip the double wall by the furnace and just get a thermostat control app to switch it on and off? Any feedback, or any suggestions for how I can provide you with better info/drawings/etc is most welcome. Thanks! Ethan