Bass amp Isolation, Need to build Monday morning.

[bronsonmestizo]

I work for a studio in Monroe, GA (15 min. west of Athens) and have been helping with, among other things, treat the room. Last night I worked until about 4am better soundproofing and treating the vocal booth. He has an old Ampeg fliptop 15" amp and tracks bass in the room/ mic's (mikes) the room with the live drums.

Problem: I used all of his Auralex last night to treat the vocal booth. He usually uses this to separate the bass and drums. I told him, the auralex won't really work to a low enough frequency, blah, blah, blah.

Solution? I have leftover sheets, 3 1/2' x 2' and 2'x2' of 705 frk, and he has am impressive workshop with loads of framing and covering materials. Bear in mind, it needs be a modular structure, not intended to completely isolate the bass from the drums, but to be able to craft the room sound in a live tracking situation.

I have to brag a little... He has amazing gear... And a load of knowhow, but he hired me to help out and bring the science/ build knowledge to the table. I know of a lot of builds for this, but what would be the best?

Ceiling height leaves a little to be desired, 8'... But over all well treated and large room. Cement floors and throw rugs in a basement, no isolation needed there...

IDEAS?

[snoopy23]

Bass is difficult to fully isolate because the waves are so big and can find their way through most rooms and materials. I would try to get a D.I. signal and use headphones while tracking with drums, then go back ond overdub the bas later with speakers and mics if the D.I. sound isn't enough. I am not sure the materials you have left will do much to effectively contain the bass.
Good luck!

[snoopy23]

Although, I did make a modular box out of 2x4's and plywood and stuffed the hell out of it by stapling comforters to the sides and ceilings. This might tame the bass enough to get a useable drum and bass take with minimal bleed.

[JWL]

Best thing you can try is to make a "riser" for the bass amp to sit on, this will decouple it from the floor and reduce structure-born flanking noise.

I'd do a "sandwich" with plywood or mdf on the top and bottom, with rigid fiberglass in between. You can cover the whole thing with cloth to hold it together (don't fasten the layers of plywood to one another or it defeats the purpose).

There won't be a lot you can do, but if much of the noise problem is flanking noise this will help a fair amount.

[oldguitars]

DI the bass, then reamp it...

[bronsonmestizo]

Thanks for the responses. I guess "Air space" is what I'm trying to replace with density... And density, I'd like to take the place of weight. My equation was broken from the start. However, we got good results. I surrounded the amp with rigid fiberglass panels to keep the cymbals and snare crack out, and DI'd the bass. There was a bit of low end bleed, but the real problem was repaired this way...

We were using an 80's Pearl 24" kick 9 ply, and two fingers deep gloss. We bought, headed and tuned a 26" "Battlefield" kick. It's a 6 ply all maple, no finish. The wood really resonates. As it turns out, the bass bleed problem I was experiencing had more to do with the kick being incapable of reaching a lower frequency than the bass, than the bass overwhelming the kick mic.

I tracked down the variables and that was it. Here I was rebuilding our studio and we just needed a different kick drum.

We use a Neve 8068 console. It deserves only the best...