@mountainsong I think the question you’re asking is very relevant.
I’m sure you’ve done a fair amount of research before investing a good chunk of change into the S3s, so you know that they are extremely transparent, current-hungry, and finicky when it comes to placement and room treatments.
I feel that some responses here glance over how much current they need to shine. And you certainly don’t want to “choke” $40k+ speakers, but give them a chance to shine.
So, these are very demanding speakers, in all practical senses.
Therefore you need a solid-state power amp (or monoblocks) that can deliver a lot of current.
They are also extremely revealing of anything you have upstream, so it’s important that the quality of your sources and pre-amp match the speakers because of their transparency and what some have described as “pinpoint accuracy.”
They’re also demanding on room placement and room treatment, again because they are so detailed and focused. Don’t skimper on room treatment with these speakers.
They are also more analytical and a bit leaner than they are musical, so, budget allowing, I would recommend a tube preamplifier (to inject some more warmth/musicality into your audio chain) feeding a solid state amplifier.
I don’t know if there are any integrated amps that would have a tube preamp stage and solid-state output stage AND still be able to handle the current delivery the S3s demand, so you may have to go with separates to optimize your set up.
It’s not the worst thing, particularly if you look at quality units on the used market.
Best of luck – tell us how it all turns out!