Living room system: class A or AB amps?

@tvad 

How high is the ceiling?

It's 10ft to the plaster ceiling, then another 1/2ft to the concrete slab.
I'm about 12 feet away from the speakers.

Regarding doubling down when impedances halves: I think both Pass Labs and Luxman M-900u do a good enough job at that.

If going for Pass, I'd veer towards the X600.8 monoblocks.

Just get the amp that sounds the best with your speakers.  The only limiting factor would be if you needed to hide the amp in an enclosure.

You'd have no problems running class A amps at hundreds of watts day and night in the living room?

Unfortunately no dealers out there with Focal Stella Evo's on demo with several different amplifiers to audition.
Let alone my considerations: Gryphon Mephisto, Luxman M-900u mono, and D'Agostino Progression mono.

P.S. I may want to have some enclosure around the amps, but easy enough to add some active ventilation with quiet fans.

@millercarbon
With your depth of experience and knowledge I was hoping for something more substantial. A class-y response that would actually help me :)

I wish I could ignore the practicality factor, but it’s a living room.

For class AB I'm thinking two Luxman M-900u's in mono.

PASS 250.8 or 350.8 asap!!

Would that be enough for the 374lbs a piece Focal Stella Evo’s? I’d rather risk a little overkill vs. underpowering them. Guess X600.8 monoblocks then?

Robert, it sounds like you know your answer about Class A.

Not so sure yet. Just read class A sounds good too without a warm-up (although better as temperature increases). I live in a tropical climate and my room temp is always at least 25°C / 77°F.
That may shorten warm-up times compared to a system in a Canadian basement in winter :)

@twoleftears

Luxman monos will give you superlative performance. Don't second guess it.

That's encouraging! Did you hear them personally? If so, with what speakers?

@fatdaddy

Did you just call your fellow forum contributors "schmucks"?

In my country, not a single Focal dealer has the Stella Evo's on demo. At $140,000 MSRP, who does? Even if they had the Stella's, they don't have the amplification to match it. So I have to travel and hear components separately.

I'm here to get suggestions and ideas (not to "listen" to anyone). That way I found out about Gryphon and the Mephisto. Which I will be auditioning this Friday. Thanks for contributing nothing but negativity.

@millercarbon

Maybe I should have chosen different words, and leave "class" out of the equation.

Little kids, pets and a living room environment may require a rack or cabinet. For these customers, size, weight, heat and safety become real factors. Nobody wants their toddler to fall face forward into a bed of sharp heat sinks. They may choose D'Agostino Momentum monoblocks over Pass Labs XS300. Because they both sound great but the Momentums run cooler and are easier to fit into a cabinet. Safer and more suitable in a living room.
You may cringe because these restrictions mean they will never hear the system's full potential. You may find it a waste of money. But why not if you have the budget to get awesome speakers and high-end components? Yes, the restrictions suck. But it beats defaulting to a $3,000 home cinema set. 

@patrickdowns

For watching TV? Okay....

Not just for watching TV. That's just a by-product because it's in the living room. I regularly enjoy long listening sessions, and that's why I'm spending this kind of money.

P.S. I got the newer Stella Evo's. You referred to the older version of this speaker, now on discount.

@onhwy61 

True. The Pass Labs X600.8 stays in Class A up to 50W, which is quite high.

@georgehifi

No, not stand-by because that means the amp is not on

I understood that, hence "stand by" in quotation marks ;)
Thanks again.

@georgehifi

I read your suggestion, thank you. The low bias button is like a "stand by" button. Before a listening session you simply press the high bias button. The Mephisto has that too.