Old school tube experts school me

[controlled_voltage]

I comb flea markets, garage sales etc for gear, records etc.
often I see boxes like the one below and have no idea what I’m looking st or what to buy
I do know the obvious tube numbers for pre and power output but I’m sure the numbers were different back in the day?
Thanks

 

[Mark Skid]

This should be good.

 

[psychodave]

Numbers really didn't change from back in the day. There were slightly different from Euro coding. for example: EL34/ 6CA7 were interchangeable, but were not the exactly same design. You just need to know what you're looking for... another example is 7581a and 6L6GC or EL84/ 6BQ5, etc.

I dont see anything useable for guitar amps in that pic.

 

[braintheory]

Numbers really didn't change from back in the day. There were slightly different from Euro coding. for example: EL34/ 6CA7 were interchangeable, but were not the exactly same design. You just need to know what you're looking for... another example is 7581a and 6L6GC or EL84/ 6BQ5, etc.

I dont see anything useable for guitar amps in that pic.

The GE 6SN7 I think would be in just my Alessandro and Schroeder amps, but not sure of much other amps out there that use octal pre-amp tubes like that. The others I don’t know of any guitar amps that use what’s in the pic