The most important aspect of any audio product is the sonic end result of whatever design methods and components are used. Perreaux decided to use MOSFETs, in part because of the similarity in their sound characteristics and operation to valves, in fact the MOSFET in effect shares the best characteristics of both bi-polar transistors and valves whilst avoiding the problems associated with them.

Perreaux amplifiers can be driven well into clipping, without generating harsh audibly disturbing odd order harmonic distortion common to bi-polar transistor designs. This inherent ability to clip 'softly' means that whatever distortion is present under extreme transient conditions will remain musical and pleasant rather than harsh and brittl