Found the 10-19 post below on the "Designer Hall of Fame" thread started in '08. Now if we only knew OV, might have a clue what's going on with this line of inquiry.
10-19-15: Realdeal
OV,who designed tube rectified OTL,using DHT tube as an OPT or any of the 7ac based tubes.Make it possible for kt66/88 or any 7ac based tube directly plugged into a 4 pin socket of a 6A3 single ended amp without amplifier mod.
Realdeal (Threads | Answers | This Thread)
10-19-15: Realdeal
OV,who designed tube rectified OTL,using DHT tube as an OPT or any of the 7ac based tubes.Make it possible for kt66/88 or any 7ac based tube directly plugged into a 4 pin socket of a 6A3 single ended amp without amplifier mod.
Realdeal (Threads | Answers | This Thread)