CHANGING FROM AUDIO RESEARCH TO AUDIO NOTE SYSTEM 

I believe there are 833 amps claiming 150 wpc.  Also, the ultra rare 1610 can probably do 80 wpc.  I tend to prefer the lower wattage, non-transmitter tube SETs, but 211 and 845 amps can be quite nice sounding. 

Wavac SH-833 monoblock power amplifier Specifications

The Wavac Sh 833 mono blocks,

Sidebar 1: Specifications

Description: Direct-heated-triode, single-ended, class-A tube monoblock power amplifier. Tube complement: one each WE437, 6550/KT88, SH-833. "Effective" power: 150W (no distortion percentage specified). Frequency range: 20Hz-100kHz. Input sensitivity: 1V. Input impedance: 100k ohms. Signal/noise ratio: >100dB (no reference level quoted).

As @larryi noted , very likely the 1610 tube is capable of considerable single tube power.

Charles

BTW the relatively common and available 805 is a DHT output tube capable of 50 watts pure class A SET.

Charles 

Hi sns my monoes are the Siltech SEPA. (2004)There were only produced 15 pairs and we sololy sold to distributors over the world.

A really cost No objekt from the former Phillips ingenier Edwin van der Kley Rynveld. Who acqured  Siltech in start of the 90’.

The used tube is a special invented nuvistor type that in this configuration is making 80 W/ 8 Ohm.

The only drawbach for me is that is actually is not a ballanced design as the rest of my system. 
Several years ago i took all gear away from the middle of the speaker and placed it on the sidewall, and am going with 10mtr IC cabels, hence the need of the ballanced cabels. At High volumen simple a must.

I must admit that i love huge speakers, “there is No substitute for cubic.” also fitts well for speakers.