the tas5611a is a high performance analog input class d amplifier with integrated closed loop feedback technology (known as purepath hd) with the ability to drive up to 125w(1) stereo into 4 to 8 speakers from a single 32.5v supply. purepath hd technology enables traditional ab-amplifier performance (<0.03% thd) levels while providing the power efficiency of traditional class d amplifiers. unlike traditional class d amplifiers the distortion curve only increases once the output levels move into clipping. purepath hd technology enables lower idle losses making the device even more efficient.