What is the most powerful SET tube amplifier?

just need to know where built and brand for my own record.

@marakanetz The most powerful SET is likely also to be the one with the least bandwidth. This is because bandwidth is really challenging for the output transformer of an SET- effectively, about 7-8 Watts is all the power you can make and still be 'hifi' (20Hz-20KHz).

OTOH if you need 100 Watts for example you can get a lot more bandwidth from a push-pull amplifier. The trick there, if you want that 'SET sound' is to get one that is properly designed, probably triode and class A; likely zero feedback too. Such amplifiers are made...

Today it's most likely the NAT Audio Magma Evo 170w class A with the huge GM-100 tube.

another set amp 100watts is siltech

The Cary (and presumeably the Bel Canto) drive the output tube grid into class A2 which significantly increases grid current and distortion. However, it isn't intended to stay in this mode of operation except for extreme dynamic peaks. Normal operation is class A up to around 25 watts as Ed pointed out.
Along with WAVAC, Legend Audio also makes an amp using the 833 tube with at least 100 watts (possibly 200?), but I don't know if it is actually a product or just a statement item. Wyetech has 45 watt SET mono-blocks, though they use two complete amp channels in parallel to produce this kind of power. Also, the company deHavilland makes a SET mono-block with the Russian GM70 tube that is a solid 30 watt.
Of course, there are those who feel that anything over 10 watts SET requires too many sonic compromises, but this will force the use of very efficient speakers. Hope this helps.

The most powerful SET amp I know of is the WAVAC HE-833, which is a 100 watt monoblock. That's almost twice the power of the Cary. At least one person is using this beast to drive his Sound Labs, which means the amp is quite capable of driving a very difficult load. The price is in the same ballpark as the Cary. Replacement 833 monster output tubes are quite reasonable - around $250 each last time I checked.

Here is the address of WAVAC's HE-833 page: http://www.wavac-audio.gr.jp/he833_e.html

Note that both the Cary and Bel Canto are driving their 845s into Class AB to get those power outputs, maybe even class B for the Cary. the 845 tube can only put out 27w in class A, at the bleeding edge (1250v), most are run at lower voltages. (1000v = about 22-23w in class A).

Fwiw,
-Ed

The Cary monoblocks noted 'informally' above are at http://www.caryaudio.com/cad1610se.html

Yes 55 watts is correct for the Cary. Issue 15 of HI-FI+ (English magazine) shows another design using the same tube which is rated at 100 watts made by the "Metropolis" company. Sorry...

So Chazzbo whould you still stay with SET or something more efficient?

The Bel Canto SET40 is 37 wpc with the 845 output tube.Thought it would meet my needs power wise with that amount of grunt but it didn't so I need to flip it.My sepakers are 93 db sensitive but maybe they have an impedance dip or maybe I just need to clean the wax outta my ears.I was supprised though.

Dweller may be thinking of the CD-1610 that is rated for 55W per channel. That's the one JA from Stereophile ranted about as only being able t output 9W at 3% THD.

Wavac has a 100 watt mono block SET amps. They are the most beautiful amps I think I have ever seen. Might be one of the best sounding I have heard. Wavac also has a 50 watt SET amp. Hi Marakanetz, Cary has a V-12 amp that is 50 watt triode or 100 watt ultra linear. The Cary 805 is not a push pull design. There is another SET amp that puts out 50 watts but I can't remember the name of the company.

I thought that 805C is triode push-pull amp so far...?

Dweller, I hope that's a mono-block because I'm ordering two :^)

Cary builds one that is 100 watts/ch. Uses a huge mother of a tube... also, sells for something like $38,000. Sorry if info too informal...

Probably Cary 805C, 50 wpc..........