Anybody who claims that switching at 50khz influences the signal and is noticeable to the ear is a big fat liar. Class D isn't a detriment. The problem with them in the past is that nobody wanted to redesign amp circuits. Anybody who made an amplifier used the same cookie cutter schematics since FOREVER!!! in order to lower R&D. Kinda makes you bitter huh? Everything is pretty much the same except components used and percentage of failure rates ;P