NOS Audio CDP

The source is a heavily modified CD player, the NOS Audio Mu2 ($1800). This is a top-of-the-line player in which Michael Thompson of Toronto’s Executive Stereo has replaced the usual DAC with a transformer DAC. This technique is not unheard of, but it is rare and usually part of very expensive players. Thompson, a personable electronic artist, explains that a specially built transformer performs all the necessary analog junctions, including current-to-voltage conversion and low-pass filtering, while allowing wideband isolation of the digital and analog sections. He goes to great pains to point out that this system generates no noise because of the passive nature of transformer amplification. He points out that the distortion and phase characteristics of transformers compensate for negative recording and digital artifacts within CDs. However, the player is not totally amplifier free: A buffer amp provides the constant load necessary for the transformer and, Thompson says, adds the least amount of noise of any type of amplifier.