wikipedia said "Theoretical power efficiency of class D amplifiers is 100%. That is to say, all of the power supplied to it is delivered to the load, none is turned to heat". Im just starting to learn about Class D and im wondering if its truly more responsible as a human to use a class D amp rather than one who wastes power that could be sent to the cone, into the thin air as heat. okay. now i'm completely sold on class D as my favorite type of solid state power in amp design. I still have love for the 6550 and the 6v6 and the 6l6, and now to include Class D. Does anyone know if the new fender rumble v3 class d have a low pass filter after the switching, and before the speak?