It all comes down to system synergy and with the right front end and the right speakers, Pass Labs are extraordinary. I have heard Pass Labs sound only so-so, but it has pretty much always been due to poor speaker synergy.
For my Audio Physic Avanti III, the Pass Labs XA60.5 has really turned out to be the best.
For my Audio Physic Avanti III, the Pass Labs XA60.5 has really turned out to be the best.