Pass Labs A/B amps vs Class A amp and Actual Power


Dumb question; how can you compare the actual power or ability of an amp to drive a tough load (such as a Magnepan) when looking at a Pass Labs A/B design such as the X250.5 or X350.5 vs one of the full class A amps like the XA60.5 and XA100.5? For example, which amps would (from a standpoint of just pure power/grunt) drive 3.6's better, an X350.5 or a XA60.5?
stickman451
As Elberoth sugggests, the XA.5 series is very conservatively rated, I can tell you that having owned the XA30.5 I would discuss it with Pass Labs, if they tell you it should be no problem, you can trust them.
I actually gave Pass Labs a call today and they were very patient and helpful in discussing the relative power(s) of their amps. They recommended either the XA100.5 or the X350.5. They felt that in my larger room and considering my history in using Horn speakers (In addition to the 3.6's I have a pair of Klipschorns) that the XA60.5 might not quite get the job done for me. All their amps 'double-down' into 4 ohms so I would have either 200 watts of pure Class A (that's a lot!) or 700 Watts of Class A/B (that's a lot too!)... And, even with the X350.5 I would get 80 Watts of Class A performance before it slipped into A/B mode; sounds like the X350.5 is a good deal and just the ticket!
There is a big difference in the sound of 'Class A' between the XA.5 and the X.5. They are entirely different amps despite their similar cosmetics.

Buy the X.5 because it is a good deal and a value component. Don't buy it because you think the Class A sound is equivalent.

In the end, both are great amps.
Stickman, are you sure that the XA 100.5 maintains Class A bias (or something to that effect, as there has been discussion here on the technical classification as to whether Class A/AB and Class AB amps technically deliver any Class A bias(?))or is the Class A Bias reduced and the Class AB increased as it doubles down?
I'm pretty sure that Pass Labs told me that all of their XA.5 and X.5 amps 'double-down', so an XA100.5 would give you 200 watts of Class A into a 4 ohm load... Pretty sure I heard them say that exactly...