My brother and I recently built a "real" recording studio to replace my home studio. As a cost-savings measure, we chose not to float the floors; but we did spend the big bucks on well-built walls, acoustic doors & windows, and dedicated HVAC. Successful? Mostly. We shaved approximately $50,000 from our budget by forgoing the floating, concrete floors (and the new walls and ceilings above those floors) that were part of the initial design; but as a result, we get some sound transmission not only between rooms but out to adjacent buildings. Not enough to bother the neighbors, but enough that if you're sitting in a quiet room across the back yard, you can hear some rumble and percussion just below the sound of the street traffic.
Our first real-world test of our construction efforts involved Jeff and Gavin (from the band Karate) rehearsing for three days in the studio with Thom Moore (of the Moore Brothers) and Nedelle. I spent a good deal of time walking around both inside and outside of the building, listening for sound leakage. The rumble from Jeff's bass amp was one of the most noticeable sounds being transmitted outside of the tracking room. On the third day, I brought in an Auralex GRAMMA isolation platform and placed it underneath the bass amp. After one song, both Jeff and Gavin noticed an immediate difference in the sound of the amp within the room. They both felt that the bass sounded tighter and more focused. Listening for the bass in other rooms, my brother and I could tell that the building was vibrating less-we heard less of the bass amp's sustain. Outside? Similar reduction.
The GRAMMA is a 23" x 15" MDF platform covered in Ozite fabric, sitting on two rails of Auralex PLATFOAM high-density isolation foam. A piece of Auralex Studiofoam is attached to the underside of the platform between the rails. The system's low weight and built-in handle facilitate moving it around. Its purpose is to isolate bass and guitar amps, stage monitors, subwoofers-or anything else that would benefit from physical decoupling-from the floor. You could probably build something very much like it, but the cost of the time you'd spend building it would set you back more than the money you'd spend on the ready-to-use GRAMMA. Plus, a DIY platform would most likely look... DIY. Anyway, let's face the facts. Whether you buy one or build one yourself, a small platform sitting on strips of foam can't replace $50,000 worth of contracted construction. But it can certainly give you a better sounding amp while providing noticeable reduction in sound transmission. I think that's money well spent. ($59.96 MSRP; www.auralex.com)