Class A amplifiers - which are considered the best

I have the Pass XA60.5 monos, absolutely love them, described them in enough messages on this board, thus won't bore you again.

As to electricity cost, letting them warm up for about 4 hours before using would get you 95% of their performance. The next level up would be 4 days, and that just does not seem worth the cost, needless to say being wasteful. But really, a 4-hour wait on the XA60.5 easily blows away most class A/B amplifiers out there. Now if you are in a rush, playing immediately after power on would already get you into the better end of class A/B amplifier selection. Nevertheless that's not the point when you purchase a class A amp.

Bob bundus, you might want to do further background check as to which ones are really "class A" amp. I know Ayre amps are all class A/B amp. None of them are class A's. Ayre is one of the better design however. I would easily pick them over the majority of amp. out there. However you don't get class A sound in class A/B amp. unless you listen at extremely low volume.

I'll add more fuel to the fire, beyond what Audiofeil said. Speaker matching is just one thing. Mine however lies in the power conditioner. If you read Audiogon messages long enough, they all sound about the same when comparing Class A amp. to something else. Needless to say, the differences between Class A amplifier designs would be less disparaging. Typical complaints about Class A amp. are too sweet and relaxed, and not enough treble.

The Audio Power power conditioner I use have 3 different electrical designs for outlets to be used with the sources (disc player & preamp). Other outlets are designed for amplifiers (by avoiding current limitation). If I set all source electrical inputs to the "balance" mode, it's an easy ride to listen for hours. The fine detail in the fabric of music is amazing as I described elsewhere. However plenty of warm up for all equipment (hours to days) must be there to reduce the softness, especially in the upper frequencies, to a barely noticeable level. The middle of the road is to switch preamp. electrical input to the "float" mode, which is in between "balance" and the unaltered signal, and the CD player power to unaltered signal. Now things are considerable more engaging. Vividness significantly increases. I can feel even more soulfulness and artistry of the performers-something that Class A amplifiers, regardless of power conditioner used, are known for. With more realism comes less distortion, allowing the soundstage to open even wider. Finally, if I switch everything to the unaltered electrical mode, it's just raw, very lively and forward. The music comes out of the speakers and brings me right into the soundstage. It's definitely the mode for your teenager children who want to boogie all night to the tune-very punchy from top to bottom frequencies. I unquestionable like the realism but there is only so long my brain can proverbially jump up and down with the music before it needs a physical break. Besides, the upper frequencies are getting a bit much, not as bad but begins to sound like my previous amplifier, which is actually rated by Stereophile as a class A (2 different kinds of "class A" obviously). The best way I could describe the difference between the last and middle mode is between live performance and studio recording where music is equalized and refined. I personally switch back and forth between the last 2 modes depending on my mood.

I own a pair of Pass XA60.5 and think the world of them.