What Class A is better? SUGDEN FPA-4 or PASS LABS XA-25

As a former speaker manufacturer, I have listened to many, many amps and I have always liked the Sudgen sound.  Clean, pure, sweet, natural. For that matter, I like Class A amps. The FPA4, discontinued in 2019, was based on the A21, so you have some very good DNA there. But is is not the same as the A21SE. The XA25 is unlike other Pass amps, so you need to hear it to appreciate what it is. It has its own sound and is close to a single ended tube sound. It is actually the one Pass amp that I like the best. Read Teajays's and the others review. I have 4 favorite ss amps and the XA25 is one, which I also own. It comes down to your ears and what is in the rest of your system. But there is something special and just right about the XA25. I hope you can find some way to compare them side by side.

Before I went toward tubes, I looked hard at both but didn't audition. So I cannot give you the experience answer you're looking for. However, one audio dealer which a lot of people respect is Gig Harbor audio and they're very nice people who carry Sugden. If you called or wrote them to ask why they deal in Sugden, they might add some data to your inquiry. Yes, they're a dealer so they'll be biased toward what they carry, but sometimes these conversations yield nuggets. https://www.gigharboraudio.com/

I have the Sugden A21se and I love this amplifier, so much grunt it defies the power expectations of most, I’m using it with KEF R3’s and it’s a very nice pairing, the Sugden is just very musical and clean. 

I have tried out a Sugden A21SE and a Pass Labs INT-25. I kept the Pass Labs. The Sugden is nice, and the Pass is nice. I felt the Pass was a better product, though more expensive so it should be. For me, sounded better and was built with a true heirloom quality. The Pass Labs INT-25 makes all of my music sound wonderful, some of it magical. Probably the most pleasing and satisfying integrated I have owned (coming from 30 years of experience with ARC, Cary, Ayon, McIntosh, Devialet, Line Magnetic, Luxman, PS Audio, Vinnie Rossi and many others). With all of that said the Sugden also brings up a similar sound in Class A but the Pass does so with a bit more expansiveness and detail. Bass on the INT25 is remarkable. 

Sugden sugcks

Sorry had to. Nelson wooopp.