Dramatic Isolation to Clean Up Bass Amplifier Sound One of the many acoustical issues faced in live performance is the acoustic coupling that happens between instrument amplifiers and/or wedge monitors and the stage.

These bass frequencies can muddy the sound from the amplifier while creating difficult feedback problems through the acoustic coupling of a mic stand and the stage. When Rock and Roll Hall of Fame inductee Stu Cook (bassist for Creedence Clearwater Revival and Creedence Clearwater Revisited), needed to clean up the sound from his bass amp on stage, the Auralex GRAMMA was the solution. The GRAMMA Isolation Riser tamed the bumps and holes in the bass performance by effectively decoupling the amplifier from the stage, yielding a uniform sound. The GRAMMA dramatically isolates any amplifier (up to 300 lbs. in weight)eliminating harmful acoustic coupling, cleaning up the sound and making the mix engineer’s life a bit easier. According to Cook. “I get a very consistent sound when floating my bass speaker cabinets regardless of the stage design. They’re light and easy to travel with, so there’s no reason to leave home without them.” Given the wide range of venues and stages his band encounters, the GRAMMA has become a vital part of the set up. “We want to be able to walk onto a stage and concentrate on giving a great performance, not worry about coupling problems. The GRAMMA is a simple solution that really works.” GRAMMA isolation risers come in two flavors: the original GRAMMA that is 23″ long x 15″ wide x 2.75″ high and the Great GRAMMA that is 30″ long x 19″ wide x 2.75″ high to accommodate larger rigs.