1938 RCA 55-B bridging amplifiers

[rackmonkey]

i can’t decide which i’m more interested in: the specs & internals or the magnificent industrial design.

 

[rackmonkey]

Did RCA end the deluxe models after this generation? Once the 76 console disappears from the catalogs, it looks like the BA series was the top of the heap.

 

[radardoug]

Cool, thanks for the clarification on no new available metal top caps.  I gave up looking.
Yes I'm sure you're right on the lower inter-electrode capacitance. 

For all the hassle of the odd-ball sockets and searching for NOS grid caps, I still have a feeling I'd prefer having those valves 

Theres a type of crocodile clip you could use, the jaws will close around a tube cap fine.

 

[emrr]

Did RCA end the deluxe models after this generation? Once the 76 console disappears from the catalogs, it looks like the BA series was the top of the heap.

Deluxe and Standard end at WWII. BA is the mechanical continuation of Economy.  The 76 is a little undefined, but to me is fits into Economy more than anywhere else, it’s the only all-inclusive package with mechanically simplified amps as part of the console. There’s consoles in the Economy line that are more ‘deluxe’ than the 76, and the Standard/Deluxe consoles are passive desks for rack amps.