[Labpro]

Quick question for Giscours owners.

I need to replace my GE 6072 phone tubes.

There are quite a few NOS 6072"A" tubes out there.

I believe the "A" has something to do with the warm-up protocol.

Can you tell me if it is OK to use a 6072 and 6072 "A" in the same circuit?

Also, is it OK to use 2 of the 6072"A" tubes in the Giscours phono circuit?

Thank you for the advice!

Labpro