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Pass Labs AMP’s- What is the best Pass Amp Sound for You from past 10 years

So I have an XA-25 and its outstanding. I’ve tested the XA60.8 mono’s and there was not enough difference to move to them; no jaw dropping moments. Don’t get me wrong they were fantastic, but so is the XA25. Looking at the 350.8 or 250.8, etc.... even in comparison the Integrated INT-250... If you love it; want to explain what you like and why? I’m wondering what others are thinking... 
My set up: Wilson Sophia II’s, XA-25, Pass Labs XP-22 pre, Merging+NADAC. 
jahatl513
audiofound
81 posts
 
Interesting the int 250 doesn't get much love here. The reviews are pretty darn good.
unsound
7,421 posts
 

@georgehifi , I believe the Threshold S 500's were rated to about 20%  Class A;  or 50 Watts. With impedance drops; as the power output doubled, the Class A output halved.

There are 20 output devices per channel for a total of 40. Though, I think something like 4 devices per side were used for the then trick Stasis circuitry.

erik_squires
17,557 posts
 
Hey OP,

Listen I don't want to hijack your thread, but I am curious if you get to compare Pass to other brands and keep coming back to Pass.
If so, I'd love to read your experience on those other brands and what you feel the delta is. Maybe not on this thread.
Thanks,

Erik
jahatl513 OP
124 posts
 
Erik_squires: that is not my experience.  Please start a new thread. I’d like to hear about it but not here. Thanks. 
georgehifi's avatar
georgehifi
10,312 posts
 

@georgehifi , I believe the Threshold S 500’s were rated to about 20% Class A; or 50 Watts. With impedance drops; as the power output doubled, the Class A output halved.

There are 20 output devices per channel for a total of 40. Though, I think something like 4 devices per side were used for the then trick Stasis circuitry.

To support 50w of Class_A in the S500 with 76v rails those heatsinks would have had to be 3 x the size. I’ve built enough Class-A’s to know how much heatsink is needed for the rail v used, some had to be water cooled.

There are 20 per channel but only 18 as outputs, two are used as drivers. https://ibb.co/9h2dGW9

Cheers George
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