Sunn Amplifiers

I found this by chance can anyone shed any light on this?
Vintage tube Sunns came in three basic flavors, 2 X KT88/6550 or 4 X KT88/6550. Some Sunn amps were a 2 X EL34 configuration. All of them were based on David Hafler and Bill Laurent’s Dynaco Hi-Fi circuits.
In fact originally the amps actually were Dynaco amps stuffed into a box. These were early top controlled split chassis amps (sort of "Vox" like), and they came with a Dynaco Mk III (2 X KT88 60 watt) or the more rare Dynaco Mk IV (2 X EL34 40 watt) power amp, both with a modified Dynaco PAM-1 preamp mounted separately on the top of the box.
Pre Hartzell (early 70's), Sunn amplifiers were not available as heads only, and were only sold in combination with a matching speaker cabinet(s), i.e; a 200S was a 60 watt head with a 2 X JBL D140F cabinet while a Sorado was the same head but paired with a 2 X 15" "Sunn Transducer" (CTS?) cab, a Sceptre was the 60 watt reverb/tremolo guitar head with a 4 X 12, Sentura II same head but 2 X JBL D15S (re-badged D130F) cab, 100S same head but with a D130F and a LE100S horn.
All of them, bass amp or guitar amp, shared identical power amp stages.

The Sunn 100s was based on the MkIII, the schematic is available online and you can see the MkIII in large part represented there. There are differences... the bias and filament supplies use silicon diodes. The simple added on front end is solid state. I have seen Sunn amplifiers with Dynaco labeled components visible in them. I have not seen a Sunn amp that used a Dynaco chassis.