Pass Labs Amp X350.5 or X350.8 anyone compare?

Ozzy, I'm breaking in XA-160.8 monoblocks. Suggest at least 40-50 hours of time with music before forming critical judgment.

This was my experience as well. The large PS caps need more time to form. Keep your chin up for at least 40-50 hours of signal.

I sense as well that the XA-160.8s have mostly settled in by 75 hours. I can see how some might perceive the .8 palette as slightly dark or tilted down. However this is deceptive, as there is also ginormous resolving power in the treble and upper mid-range, that emerges without over-emphasis from the most surreal black background that I've encountered in an amplifier. I'm still getting used to it, and am not yet persuaded whether the effect is entirely natural or subtractive. But the attendant absence of distortion, ringing, grain, and glare is definitely a good thing, and the system has never sounded so smooth and seductive.

It's an endlessly interesting hobby. This evening I removed an Afghan rug from between the .8 amps(on Stillpoint Ultra SS with coupling bases) and Merlin VSM(on Stillpoint Ultra 5). This redressed the frequency imbalance with a more prominent upper midrange and HF, with improved LF definition. It's now about as perfect as imaginable. Star Sound Apprentice platforms are en route for comparison.

Joecasey, The .8 monos are my first Pass amps. I've heard .5s only at shows, and too long ago for comparison.