Who has, and is using daily, the oldest Pass Labs amp(s)?

Joe, what preamp and speakers are you driving it with and can you describe what makes it so special?

I'm using the Luxman C900u, but Mike insists the Ref 10 kills with it. I'll take his word. :)

I've been using the Revel Studio2. For me, it feels like it has more than enough power. I'll be honest, coming from the Dags, the first week with the XA25 was a little rough. Not smooth and a little aggressive on top but after a few days in, it really started to open up, smooth out and sweeten up. Of course the price delta is substantial but now, it's holding its own.

Slightly more tube-like compared to other SS amps. Very natural vocals. Piano is wonderful. Sweet, pure and delicate tone with plenty of meat on the bone. I don't crank my music but it goes loud enough for me. Bass is a little rounder and fuller than higher wattage SS. The last review stated it tops out at 80wpc @ 8 ohms and 140wpc @ 4 ohms. My Studio2 are about 6 ohms and works great.

I can only imagine speakers like the Verity Othello or Mike's AG Duos (or Unos for that matter), or any slightly more sensitive speakers. OMG! Love this amp. While high (and higher) power amps are necessary and have their place, I ultimately prefer simpler, more modest amps, so long as they are up to the speakers at hand. The XA25 seems to be an open window to what is the best of tubes and SS. An absolute bargain.


I feel for you Joe, tough job but someone had to do it :)

Hahahahaha, I agree. It's a tough job but I'm getting through it.
 
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I use an X250.5 which runs at 126 degrees (to the touch). It heats up my modest sound room which is usually 5 degrees hotter than the rest of my house, when listening. The meter does not move, meaning it is running in class “A”. It needs one hour of warmup. I have absolutely no motivation to upgrade. It does not offer crow-bar control, but plays beautiful music and is as dynamic as hell. For me I am all set in the power amplifier department.
 
I use an X250.5 which runs at 126 degrees (to the touch). It heats up my modest sound room which is usually 5 degrees hotter than the rest of my house, when listening. The meter does not move, meaning it is running in class “A”. It needs one hour of warmup. I have absolutely no motivation to upgrade. It does not offer crow-bar control, but plays beautiful music and is as dynamic as hell. For me I am all set in the power amplifier department.
It's kind of a bummer that it takes an hour to sound its best. You don't leave it on all the time, do you?
 
It's kind of a bummer that it takes an hour to sound its best. You don't leave it on all the time, do you?

Dear Chicago: A bummer ? No, that’s an absolute pleasure. My tube preamp needs 4 hrs before it starts to perform. And I would never leave a class “A” amp, or anything biased into class “A” , on all the time. My X250.5 is biased into class “A” for 25 watts. Anyway, I live in the lightning capital of the world. If you want any hifi at all, use the on/off switch religiously. Better yet, turn off the power conditioner. I do both. I unplug everything with the threat of really bad stuff coming my way. And my whole house is surge protected. But a lighning hit could burn the whole place down. I won’t be worried about my hifi then. Just my wife and daughter.
 
I used to leave my x250 on but in standby. When coming out of standby it took about 45 minutes to open up. Just like a tube amp. My Coda is similar, the Levinson to a lesser extent, it sounds better after some time but not as much time as the other two.

Anyone know if this is a trait of Class A. That would make sense if true, the Levinson is less biased into Class A. I never noticed the difference on Krell, which I believe even less Class A bias than any of them.
 
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