What are the advantages to a Class A amp & what are the trade offs?

I've never had a class a amp but am considering one now. So what am I getting myself into?

@artemus_5, I would have my 100w version modified to run in Class A, but it is powering a loudspeaker which contains magnetic-planar drivers, known for their very low sensitivity. Not as much so as Maggies, but close.

I for years used a 25w/ch Class A ss amp with my old QUADS, and that was a magical combination. If I set them up again, the amp designer alluded to in my previous post offers a real nice little tube amp, available in both Class A/B (35w/ch) and Class A (25w/ch) versions, I will definitely get the 25w version for the QUADS. The QUAD Mk.2 amp was only 15w, and that was plenty for the ESL.

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I think people underestimate the amount of power required for the fast transients that typically occur in music, all the time in symphonic music. The Gryphon Colosseum can generate over 4000w instantaneously. It has two huge capacitors that can store 340,00microFarads. 

Low power amps have never done much for me. There is something about having a huge reservoir of power to draw on that makes musical reproduction so effortless. I don’t play at high decibel levels, I just like the clean and effortless sound I get from my 175lb Class A amp, lol.
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