What are the weak points of Pass amps and pre-amps ?


Though there are perhaps better transistor amps, but Pass seems to be an excellent choice for many.
What is your experience with them, if you could elaborate ? Integrateds as well.
inna
@medwardo - I have the X250.5 driving my sophia 3s and have the itch to move to an all class A. Even though the X250.5 offers the first 25W in class A. I spoke with Pass and they didnt think highly of a move from the 250.5 to the XA30/60.5. They did mention that a move to XA100.5 will be very rewarding and worth the move. Is your XA25 able to drive the Sophias well? They are known to dip well below 2 ohms at low frequencies.
pistha, while you were talking with Pass Labs did you ask them their opinion regarding the XA25 driving your Sophias? I ask because I believe my speakers also dip rather low although I only know their nominal impedence.
A few years ago I bought a pre-owned Pass INT-150.   I replaced a Wyred4sound 4 channel amplifier, because I no longer needed to bi-amp.  Talk about going from apples to oranges... The Pass was kind of an impulse buy.  I did not compare to anything else at the time.  I can't really come up with any weak points other than that yes, they do run very warm.  That is intentional though.  I don't plan on changing unless some other system change forces me to.  I can envision a scenario where an integrated would not be appropriate, but for my system now, I prefer the convenience and the sound synergy of the Pass integrated.
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I do not know Troy and have never shopped in his store. I enjoy his posts. While he certainly has some motive to promote the brands he sells, his thorough and knowledgeable insights allow me to learn about large, heavy and expensive gear w/o having to buy (and sell) everything out there. I purchase from (the few remaining) brick and mortar stores locally as well as from retailers and private sellers on A-Gon. I do not post very often these days, but do read many of the A-Gon threads. At 61, & with a bad heart, my audio addiction has become more difficult to feed. I no longer find it at all easy to transport, unbox, set-up, re-box and ship large and heavy equipment. Thanks to Troy and others who post and provide insight to the fine Audio gear that is becoming more and more difficult to hear in stores and audition at home.