Recommend tube amp for $3.5K used

I have an ARC VS110 and it meets all of your criteria and is right in your price range. I haven't heard anything under $10k that would make me want to upgrade. BAT would be a good alternative to also consider.

Rogue M-150 Monoblocks. 150 watts Ultralinear, ~100 watts triode. Can be had for around $3k used. Has the qualities you're looking for.

If you wanr solid bass, you may just need to Bi-amp to get the best results, I have an Aragon 4004 and it gives great bass, although my top amp is still solid state I hope to one day try tubes.

Almost any monoamp by Quicksilver will fill your requirements. Probably the 120-watt V4s will deafen you quite happily. QSs ALWAYS sound good and are quite reliable.
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Great speakers and preamp. Here are the amps I would suggest and in the order of preference.

CJ MV 60 ($1600 or so used)
Vac 30/30

If 100 wpc is what you are looking for then I strongly suggest the McIntosh 2102. It can be found used in your price range.

You're not asking for the moon. You're asking for a McIntosh!
The new MC275, new or used, would fit the bill. It puts out near 90 watts per channel. Silent as a mouse.
Personally, I prefer the look of the MC275 over the MC2102.

It sounds like you are set on a tube amp, but are you open to solid state? The reason I ask is I was previously using a Cary V12i that offered 50 watts triode and 100 watts ultralinear, which appears to be enough to drive your speakers (if you decide on Cary I might recommend Cary modified AES Six packs as an alternative). I was using the Cary with a Joule Electra LA-100 MkIII and the combination was very synergistic. I recently switched to a TRL D-225 and combined with the Joule Electra I am getting the sound you are after. This is a very transparent fatigue free set-up with excellent imaging, soundstage, and micro/macro dynamics. The bass is to die for and I never realized the amount of roll off on the low end with the Cary amp until I plugged in the D-225. Cost is $4k new with a no-risk trial period.

From a tube perspective, before settling on the D-225, I was looking at both high powered push/pull and SET designs, as well as the flea powered SET amps. Unfortunately my speakers are not as efficient as yours, and like you my preamp and speakers were not going anywhere. The tube amps I was researching which I would recommend are VTL, Berning, and 3-D Audio (custom made SET amps at a very reasonable cost).

Best of luck with your search.

I have owned the Sonata speakers and the CJ MV60 amp. The Sonata speakers are very smooth sounding and easy to drive. They do respond well to more watts however. I pick the CJ MV60 first and the Vac 30/30.

Why CJ first?
- only $1600 used
- 95% of the Vac amp in overall sound
- cost to retube is much lower - those 300B tubes are getting more and more popular and expensive.
- the CJ highs are extended with sparkle which the smooth sounding Sonata will like
- the CJ has more power and the Sonatas like that also they really open up with more power.

The Vac 30/30 is wonderful sounding and it would also be a great choice. Mids cut from the same cloth as the Sonata - so smooth and intimate. Nice synergy with the Sonata.

The CJ gets your there for less money and lower tube costs.

Just my thoughts.

I heard the Sonatas (version III) powered by Audio Valve Challenger 140 monos and this combo was really amazing: rich, vibrant, dynamic and beautifully detailed. The Sonatas can be driven by low powered SETs but they really open up dynamically with more powerful tube amps. The Challengers put out 110W with EL34s and 180W with KT88s.

MV 60 is great ,I own the MV55 and agree the sonics are excellent,BUT member "pdbeher"is asking among others a solid bass which brings the Rogue Zeus into my mind,I was A LUCKY guy and found one in my area this week,well I bought it,I am happy!!!!!!!!!!It will be going into a biamp system with the Rogue M150'S doing mids/highs,while the Zeus will push bass on me Aerial 10T.I am getting there.
George

I own a Vac Renaissance Thirty/Thirty MKIII and the Berning ZH270 and listen to similar music through less efficient Sonus Faber speakers. The Berning is transparent and dynamic, but when it comes to air, soundstage, detail and the emotional impact of the music, my vote goes BIG time to the VAC. As for biamping, I try to keep things as simple as possible... it's easy to lose the magic as things get more complex. Minimize electronics and cabling, maximize speaker positioning and room acoustics. Good luck and have fun!

I'll put in my Happy New Year recommendation for the Aronov Audio LS-960 which sounds like what you requested. Sorry that Santa missed your house with this one.
With its used price down in the $1100 range, it is definitely the "made in USA" bargain among many fine recommendations. Even new, it doesn't require stretching your budget.
I have been a voice in the wilderness on this company for almost as long as my Audiogon membership. I am guessing new buyers are relatively few now that the company sells direct, and the company resolutely refuses to jazz up their website.
Even though my support is kind of on auto-pilot, among other positive attributes, the bass is truly surprisingly wonderful and goes a long way toward showing why this has always been a really fun part of the audio addiction, long before kids started putting sub-woofers in their car trunks.
I need just one more true believer to join my committee to find deserving homes for a deserving amp. Apparently, other Aronov owners are the strong, silent type.

Try a Blue Circle BC28. I had one but sold it because I needed to consolidate into a multichannel for space. I would buy it again if I had the room. They are tough to find used, but if one does pop up, I would tell you to give it a try.