Is it safe to mix brands of power tubes?

[BABMusic]

I have 3 sets of extra EL34 tubes that all of them fall into a safe bias range of 31 mv to 37 mv. The brands are JJ EL34IIs, EH EL34, and Tad EL34. Is it safe to mix these brands in a 50 watt head that uses only 2 power tubes?

 

[311boogieman]

Not the expert in the room but generally - yes.

That said, you mentioned 'sets'. How many of each? I mean, obviously you want to match the 2 that are closest in bias and using the EL34II last if possible - as I don't know the physical/technical differences with the IIs. I do have some of those JJ EL34IIs and JJ El34L and like them a lot. Do you have your own probe/tester?


Actually - you should be fine with these too...

"The JJ EL34II (Mark II) is a redesigned version of the standard JJ EL34, featuring a taller, domed bottle and improved, crimped plate assembly rather than spot-welded plates. Technically, the II offers a fuller sound with improved lower-mids and bass response, sitting sonically between the standard JJ EL34 and the more aggressive JJ E34L"

 

[BABMusic]

Not the expert in the room but generally - yes.

That said, you mentioned 'sets'. How many of each? I mean, obviously you want to match the 2 that are closest in bias and using the EL34II last if possible - as I don't know the physical/technical differences with the IIs. I do have some of those JJ EL34IIs and JJ El34L and like them a lot. Do you have your own probe/tester?


Actually - you should be fine with these too...

"The JJ EL34II (Mark II) is a redesigned version of the standard JJ EL34, featuring a taller, domed bottle and improved, crimped plate assembly rather than spot-welded plates. Technically, the II offers a fuller sound with improved lower-mids and bass response, sitting sonically between the standard JJ EL34 and the more aggressive JJ E34L"

I have one matched set of each of those brands I mentioned. The EL34II tubes are slightly larger than the EH EL34, but they are about the same size as the TAD tubes. They are all 25 watt tubes, so I was thinking it might be okay. EH are set to about 35 ma, TAD are about 34, and the JJ is weird because one tube is reading 31 ma and the other reads 37 ma.