Living room system: class A or AB amps?

Would class A be suitable for a living room system? Apart from hi-fi listening sessions, it's also used a lot for watching TV.

Would it make more sense to get good class AB amplifiers, which can be switched on permanently without drawing huge amounts of power? I wouldn't want to warm-up an amp first before getting good sound.

For this system, I have so far only purchased the speakers: Focal Stella Utopia Evo. Room is big: 1,200 square feet with openings to hallways.

I'd consider to pair them with Gryphon Mephisto and Pandora. But that's class A...

Opinions and amp suggestions are welcome!

robert1976 OP The low bias button is like a "stand by" button.
No, not stand-by because that means the amp is not on, but a low biased high wattage Class-A/B amp that you can just leave as a warm up or use for non serious listening, eg: parties, dinner parties, background music etc etc. No heat or big Class-A power bills.

Then if you want to listen seriously you just press the medium or high bias buttons, and there’s no wait time involved to listen to great Class-A sound.

Cheers George

FWIW, the Pass Labs x250.8 gets no hotter than a warm (not hot) cup of tea after running for hours. (You could keep your hand on the amp for a long time...not that you'd want to.)

No, not stand-by because that means the amp is not on
I understood that, hence "stand by" in quotation marks ;)
Thanks again.
In moving to a Class A amplifier, the main thing to consider is heat dissipation. If you have very efficient loudspeakers that will provide the level of sound you prefer in your living room, using a Class A amp should not be too much of an issue. You would most likely be able to get by with a relatively low power rated amplifier, either tube or solid state, and not worry about locating the amp inside a cabinet, for appearance purposes, provided the location has some reasonable ventilation as well as sufficient surrounding space inside the cabinet. I'm not sure what factor is prompting your question. 
Personally speaking, there are many fine sounding Class A/B or even Class D amps that may satisfy your audible enjoyment. I find that the majority of quality built Class A amps on the market tend to be a bit more pricey than A/B or D class amps. I'd take a serious look at the rest of your system. If the dollar investment doesn't exceed, say $10K, you may not reap enough sonic benefit to justify "CLASS A" expense, to say nothing of whatever appearance factor you may be trying to achieve.
robert1976: "Did you just call your fellow forum contributors "schmucks"?"

Hello robert1976,

     I believe he actually called his fellow Audiogon members "schnucks".

     According to The Official 2020 Audiogon Forum Discussion Rulebook, often informally referred to as "The Bible", it unequivocally states the following:

     "If an Audiogon member calls another official member a derisive name but misspells that derisive name, for example intending to call another member a "schmuck" but misspelling it on a post as "schnuck", then it is not only officially permitted by Audiogon for fellow members to refer to this mentally challenged member by numerous similarly derisive names without penalty for a period of 1 year, it is in fact highly encouraged.               Furthermore, if the offending misspelling member is a repeat offender, such as our especially dimwitted member bigdaddy2, then members shall feel free to strike down upon thee with great vengeance and furious anger those that attempt to poison and repeatedly misspell the English language.
     According to a recent statement from the author of The Official 2020 Audiogon Forum Discussion Rulebook, Samuel L. Jackson, "our rulebook committee has just unanimously decided that fatdaddy2's misspelling of 'schmuck' as 'schnuck' represents such a major mental malfunction and high degree of schmuckery, that, beginning with the 2021 edition of our Official Audiogon Forum Discussion Rulebook's Supplemental Dictionary, we will be placing a picture of fatdaddy2 as an example in the dictionary's entry for the word 'schmuck'. "

Thank you,