Balanced Low Power Tube Monoblocks?

TVAD -- I don't know much about them, but the Einstein MK60 and MK23 appear to fit your requirements, other than price. There is an MK60 listed here now for $13.5K (the listing shows msrp of $32K). I'd assume that the MK23 is considerably less expensive. Here is the sales brochure on them:

http://www.sensusaudio.com/images/einstein/Einstein_ProdK_engl.pdf

Best,
-- Al

Gee, looking further at the Einstein brochure, they claim damping factors for the two amplifiers of 90 and 45 relative to 8 and 4 ohms, respectively, even though they are OTL. Pretty remarkable, assuming it is true.

Best,
-- Al

Tvad- Let's see, balanced mono-block 60 wpc max. Three recommendations come to mind, in no particular order:
1. Atma-sphere M-60
2. Atma-sphere M-60
3. Atma-sphere M-60.
Power tubes are pretty cheap, service is extraordinary, used price is WAY less than $5k. Reported to work well w Audiokinesis.

09-02-09: Swampwalker
Tvad- Let's see, balanced mono-block 60 wpc max.

I should have left this open ended.

You guys are taking the max power rating too literally, and I failed to mention
in the initial post that my intention was to use the monoblocks with high
sensitivity loudspeakers.

With high sensitivity loudspeakers, more than 60 wpc would be overkill.

If leaving the max power rating open ended produces more suggestions, then
let's assume no max power rating requirement.

Another choice might be the EAR 861. Not easy to find used but it might be just the ticket. The circuit is fully-balanced input to output (and has balanced inputs, after all that's where designer Tim de Paravicini's roots are), and direct-coupled. It uses an interesting method to get triode out of a pentode tube (ties Grid 1 to Cathode, Grid 2 is signal, Grid 3 is floating) and the result is highly linear. It uses an EL519 tube reasonably low in its operating range, and the tube naturally has long life. Barring accident or bad luck, one set of tubes should last you a very long time (operating life of the tubes is something like 15,000 hours I think, so 3hrs a day for 15 years?).

One stereo amp ouputs 32W but they can be bridged, so you could start with one, and add a second later when you found it. The EL519 Enhanced Triode Mode circuit sounds really wonderful. I am frankly surprised it hasn't gotten more press over the years. I have an 859 but would love a pair of 861s if I could ever find them used.