Why would anyone want class AB amp when class A always sounds better ?

I have a First Watt Sit-3. (Class A)
It does not get hot.
18 Watts can provoke ear-bleeds with Cornwall IV's.
Efficiency?
YES! ;-)

Hi,
I compared the sansui AU-777A and sugden A21, i preferred Sansui, and my best integrate amp is Sony ta-5650, really better than two amps.
The sound of the Sony is the same than pass first watt SIT (V-fet transistors), the new name is SIT.

Reading all of the responses from a simpleton’s point of view is very interesting. But the ultimate measure for any piece of hardware is the one thing that’s totally unique for each person. How their complex inner ear relays information into the brain, which works out what’s pleasing to the listener. Not to mention the endless variables that change our hearing over time. You can’t tell someone there wrong when you don’t have their ear and brain.  Never mind the biases we have from where and when we were raised  

What’s the best amp made?  It’s the one I have.  

You may fire when ready

Hello. Interesting debate. I’m in the market for integrated amp to pair with my Goldenear Triton 2+ speakers. In the next couple of weeks I want to demo Pass Labs Int-25, McIntosh Ma-352, Luxman 509/507 590/550 depends what dealer will have in stock and maybe even Arcam Sa30(first 20w in class A)
I don’t care about measurements or numbers,all I want to hear is beautiful music. I rarely go over 85db in my medium size room so I think any of those can do that. A,A/B,G.One of them will win.
Cheers

@kren0006 wrote:

"As a direct example, some feel that the Luxman 509X class AB at $9.5k sounds better than the Luxman 590axii class A at $9k. Can’t get much more absolute-busting than that. Same company, both integrateds with same features, essentially same price, both current products."
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I thought that too (and I own the L-509X), but did you know the L-509X is both A and A/B?  It delivers the first 6 watts as "pure" Class A then transitions to A/B for the rest of its rated output.

I confirmed this with Luxman USA during a discussion of the L-550 (which is also a hybrid A, A/B, not just A)

Quote from Luxman USA email

...The Luxman L-509x is an excellent amplifier. It is considered “top of the line” and most recently introduced Luxman integrated amplifier model. It features circuit and construction details/refinements not present in (earlier introduced) the L-550aXII and L-590aXII.

L-509x is biased such that the class-A operational envelop approaches 6 watts/channel into an 8 ohms resistive load. At lower (or higher impedances) class-A operation transitions to class AB at lower output. (i.e. near 3 watts/4 ohms resistive load)

Just tossing that into the pot for consideration.