What is your experience with amp power?

My 45w Primaluna EVO 400i and my 35w Pathos TT Anniversary sound so much better than any HP amp I've tried on my Focal Scalla Utopia. For instance, they have more bass, more punch and more control than my 333w / ch Bryston 6BSST2, which ended up in my separate HT system. By chance, an Isotek Titan power block and Nordost Valhalla power cords help a lot in terms of "punch". Primaluna is now driving my Devore O/96s and the Pathos for the Scallas is definitely a keeper

One of the best systems I’ve heard had tube, 40x2 watts going to some Acoustat speakers with a couple of small subwoofers. With the lower bass removed from the main speakers, 40 watts was more than enough power.

The "high power" tube amp that I like a lot is the Synthesis A100 (rated at 100 wpc).  That amp runs tubes of my liking-KT66 in pushpull-so it is sort of the exception to what I generally like and dislike.  If someone truly needs much more power, even though I am a tube fan, I would suggest looking at solid state because, to me, many high powered tube amps sound hard and brittle (some call it "glare").  These days, solid state does not sound harsh or "grainy" (terms commonly applied to solid state in the past); to me they sound a touch lifeless at modest listening levels and are not quite as engaging (one's mind tends to wander instead of being pulled into the music).  There is no doubt that solid state can deliver very tight and punchy bass, but overall, it is still tubes for me.  I also don't have a particular preference for tube topology--I like some pushpull amps, single ended triode amps and output transformerless amps.

@curiousjim mentioned Acoustat. For years I used a pair of Hafler DH-220s running in bridged mode to power them and the RH Labs sub I have. This provided about 440wpc. Then a few years ago someone pointed out to me that electrostatics aren't exactly stable impedance and that the bridged mode was not an optimal set up. It was a simple enough experiment to change things by flipping the bridging switch and moving the speaker cables to a single channel on each amp. 

The difference in sound was astounding even though I was only providing 100wpc to the speakers! The detail and depth was greatly improved and the bass was still authoritative. I was amazed. (And my butt was sore from kicking myself for wasting all those years! 🙄)

The point I'm attempting to illustrate is that power is only one factor to consider. Compatibility and quality should also be carefully considered in your choice of amplification. BTW, I wound up with an ARC VS-110 which is about 110wpc and I'm happy as a clam. While it doesn't go to the subterranean depths of the solid state Haflers, it does everything else very, very well. 

Hope these thoughts help your hunt.

Happy listening...

Here's a real-life experience that, IMO, about sums this up:

I and a friend spent some serious seat-time with a pair of Aerial Acoustics 6T speakers (90 dB for 2.83 volts at 1 meter on axis; 4 ohms, 3 ohms minimum, low reactance; power requirement 25 watts minimum, >50 recommended) in a scheduled and well-orchestrated audition (same sound room; same acoustics; same day; minute or two between A & B listening sessions; same music; etc.). BTW: If you've got the dough and the right power source for these Aerial 6T, they are hard to beat, if that's even possible in their price range. The power source used for the first listening session was a MAC MC275 rated, conservatively, at 75 WATTS into 2 channels. Forget what the pre-amp used was but it, too, was a MAC. Minutes later, the MAC MC275 was swapped out for a MAC MA5200 rated, conservatively, at 100 WATTS into 2 channels. Within seconds (i.e.  you didn't have to listen long or hard), it was quite obvious the MC275 was able to make those Aerial sing! Did they sound better or even as good with the MAC MA5200? NO WAY! They still sounded very nice. However, the beefier power supply of the MAC MC275 and the current it could provide was immediately palpable. It's not he WATTS. It's the power supply.