What does the written number on El34's mean?

[ledvedder]

I have a pair of Electro Harmonix el34's. They have 20 and 21 written on them. I also have a pair of JJ el34's that have 40 and 41 written on them, that came in my Origin 20. What do the numbers mean? Is it OK to put the EH tubes in it?

 

[thetragichero]

cathode biased el34s? yeah you should be fine

 

[william vogel]

I have a pair of Electro Harmonix el34's. They have 20 and 21 written on them. I also have a pair of JJ el34's that have 40 and 41 written on them, that came in my Origin 20. What do the numbers mean? Is it OK to put the EH tubes in it?

You’ll really need to be more specific like it’s numbered on a TubeDepot label or Apex Matching label fixed to the base of each tube or it’s printed on the glass, etc. My first guess is it’s a match rating because the numbers are close on each pair you describe but that’s the best I can do with the limited information.

 

[paul-e-mann]

I have a pair of Electro Harmonix el34's. They have 20 and 21 written on them. I also have a pair of JJ el34's that have 40 and 41 written on them, that came in my Origin 20. What do the numbers mean? Is it OK to put the EH tubes in it?

If you have a fixed bias amp and you buy replacement tubes and match the numbers to your old tubes you dont have to bias your amp. If you have a cathode bias amp those numbers dont mean anything. Pretty sure your Origin is cathode bias so you can ignore them.

 

[StingRay85]

Could be Maxi Matcher values for mA on 400V -36V bias

But 20-21 would be on the very low side. 40 would be very strong tubes.

 

[thetragichero]

the numbers mean nothing (besides their proximity to each other in pairs/quads) without their test conditions being clearly stated. i would disregard the difference between each pair because it's meaningless without that data

 

[Angus88]

It's just a number for the matching of the tubes