Changing tubes help

[Gibbyage]

So I changed out my 6l6 tubes in my dual rec and put in el34.

I was wondering to change the smaller tubes towards the front of the head if they need to be mesa tubes. I bought four 12ax7lps sovtek tubes for my 5150 but was wondering if I could install the sovtek tubes in my dual rectifier.

And three of the four sovtek tubes have 00 01 on them and the other has 00 02 on it. Does this make it unsafe?

 

[dennq45]

Pre amp tubes are self-biasing. Install the Sovteks and have fun.

 

[Gibbyage]

Thanks for the reply. So them being different in 00 01 and 00 02 is ok.