I recently picked up, for a good price, two NOS NIB Amperex 5894As which are a more modern version of 829Bs, perhaps a little less maximum power and voltage capability, but more power capability than 832As. They have the same pinout, and use the same "septar" sockets.
They look like this:
RCA data sheet here:
http://www.mif.pg.gda.pl/homepages/fran ... 5/5894.pdf
I have used these tubes before, in their original purpose as VHF (144 MHz) RF power amplifiers, wich excellent results. There are a couple of 144 MHz repeaters in southern NH that still run great with the tubes that I installed in them.
trying these tubes in audio will another "after the move" project....
The driver for the 832 amp uses 12AT7s, in a circuit fairly similar to that of the ST-35, voltage amplifier and "cathodyne" phase splitter.
/ed B