Quicksilver amps an appropriate match for Wilson Sophia?

02-11-15: Allison2
Wilson Audio Specialties Sophia loudspeaker Specifications
Description: Three-way, floorstanding, reflex-loaded loudspeaker. Drive-units: 1" (25mm) inverted titanium-dome tweeter, 7" (178mm) paper-cone midrange unit, 10" (254mm) aluminum-cone woofer. Frequency response: 29Hz-22.5kHz, +0/-3dB. Sensitivity: 89dB/2.83V/m. Impedance: 4 ohms nominal, 3 ohms minimum. Recommended power: >12Wpc.

I'm sorry but I don't consider the Wilson Sophia to be a sensitive speaker. I'd call it a medium-low sensitivity speaker.

Also note that the spec says "89dB/2.83V/m. Impedance: 4 Ohms". Usually, the industry "standard" is to measure the speaker sensitivity using 1W into 8 Ohms at 1m away.
If the speaker is 8 Ohms, the RMS voltage works out to be 2.83V & one is feeding the speaker 1W.
If the speaker is 4 Ohms & one still uses 2.83V, then one is feeding the speaker 2W (not 1W). So, the Wilson Sophia has an artificially elevated sensitivity simply because it's being measured using 2W of input power (not 1W).
So, subtract 3dB from the Wilson Sophia sensitivity - that makes it an 86dB/1W/1m speaker.
Hence my saying it's a medium-low sensitivity speaker.

When you are sitting, say, 10ft from the speaker, the SPL at your listening chair will be 10dB lower due to volume drop-off by the square of the distance of speaker & you + some absorption of sound by the room, furniture, carpet, walls, etc.
So, you're really going to be hearing 76dB SPL for 1W fed (by your amp) into the speaker.
You say you don't listen very loudly - that's a bit nebulous if you don't give a SPL number. Let's ASSUME that you don't allow the average SPL to get any higher than 86dB at your listening chair. That means you would need 5W/ch - this would give you an 83dB SPL at your chair + 3dB due to stereo/using 2 speaker for a total of 86dB SPL.
Then you should allow another 10dB for dynamics - sudden elevations of SPL due the program material. So, you'll have peaks hitting 96dB SPL. Or, 20dB higher than the 76dB SPL you were getting with 1W into the speaker. 20dB in power is a factor of 100. So, you'd need a 100W/ch amp to ensure good dynamics when you limit your average SPL to 86dB.
In reality a lot of music would feel restrained if the SPL was limited to just 96dB for the peaks. Classical music is just one genre. There are many genres where peaks hit a much higher SPL if allowed by the amp & allowing these peaks adds to your overall music listening pleasure. So, requiring a 150W/ch or a 200W/ch is very much within the norm.
You can see if you want free-flowing music i.e. music that does not sound restrained, you need quite a lot of wattage very quickly. Something many people do not keep in mind.....
Needless to say, unfortunately, the amp cost goes up exponentially....

This may explain why I've only been able to find reviews and comments matching the Wilson Sophias with fantastically high powered tube or solid state amplifiers. In my space, I mate every amplifier I own with new speakers, just to see (hear) what happens.

No, no, no. I have owned the MiniMites, and with 88dB, 8-ohm speakers, they reached a dynamic ceiling at below what you would want with Sophias. I liked them but did not LOVE them like I do my Pass M2.

BTW, EH EL-34s in my Mini-Mites sounded brittle and splashy as did the Chinese 12AX7s (RCA 12AX7A's were WAYYY better). IF you go for 34's, seek out SEDs.

Just picked up a pair of mid monos and they seem to work well with the Sophias. Haven't yet had a chance to A/B/C the MiniMites, the MidMonos and the VTL ST150, but that'll be happening real soon. So far MidMonos aren't shy with detail, dynamics or bass. Enjoying the music while I cool down from all that amplifier lifting.