OTL amps, my pick for the tube used.

The 6LF6 used in my Futterman H3aa's is capable of decent current delivery. This is a TV tube designed for use as a horizontal deflection amplifier in b&w TV's.

Those who are fans of the Futterman H3aa should keep an eye out for a new OTL designed and built by Roger Modjeski that uses the 26DQ5 which is also a sweep tube designed for very high peak currents. If I remember correctly Roger mentioned the 26DQ5 tube is capable of 1 amp of current and in this circuit, which he designed as a tribute to Futterman, uses 6 output tubes per monoblock, 3 to pull up and 3 to pull down, giving an output current of 3 amps into any load.

giving an output current of 3 amps into any load.

I know this is a good figure for an OTL, but I have to laugh when I look at the flagship models of my amps (100-amps continuous)

https://ibb.co/59M4ZZp

https://ibb.co/VHgjcXJ

We had a pair of these here https://img.ukaudiomart.com/uploads/large/1760474-jbl-array-1400-speakers.jpg driven by the big Fluterman OTL’s, and they were sucked dry on transients when we wanted some medium level out of them.

Cheers George

Obviously people named George need not apply. This will be an amp for more efficient loudspeakers and for people who have some kind of emotional attachment to Futterman. I trust Roger will be able to build one that won't blow up. 
George, you should build one with your 6C33C tube and see how it goes.
Atma-Sphere corners the Market in OTLs as far as this guy is concerned. I have no interest in any amp that can not do at least 200 watts.  
Mike

I’ve always been interested in these which use the 6C33C but at $22k/pair they are out of my ballpark:

http://www.atma-sphere.com/Products/#Novacronhttp://