mixing/matching tubes

[chesterburmingham]

ok i've been thinking about using two 6l6 and two el34 tubes in my RM100M and i was just curious about what anyone might have to say about that...
to people who've done this before - how does this sound?
to anyone - any recomendations for tubes? i've been thinking tung sol, jj, or sovtek but some input would be appriciated.

 

[scotty]

http://mtsforum.grailtone.com/viewtopic.php?t=232&highlight=integrated+quad

 

[MTS_07]

In that thread they talk about biasing the e34l's at 45mv and the l6l at 35 but in other threads ive read they must all be biased within 2mv of each other so what the hell is right?

 

[muudrock]

You'll want to bias the EL34's at their correct bias voltage around 32-40 mV. Likewise, bias the 6L6 tubes at their correct voltage 25-35mV. Only tubes of the same kind should be biased withing 2 mV of each other. You wouldnt want 6L6's biased the within 2 mv of EL34's. They wouldn't last long and the amp would probably not sound so good. Bias your 2 EL34's as close as you can to each other. Do the same for your 6L6's.

Also keep in mind that ther are EL34 and E34L tubes and they do have different bias voltage settings.

EL34=32-40mV
E34L=35-42mV

 

[sir riff a lot]

just to chime in on this one,
I already did this today I biased the el34'a @ 38 and the 6l6 @ 31
it sounded pretty good.

my only question is , once you have biased them the manual says to check the difference between the pairs and if it is more than 8mv to get a better matched pair. (mine was 8.5)
will the pairs ever match when you are mixing tubes like el43/6l6 ?

in the end I pulled the el34's out just to be safe and am just using the 6l6's (it only bedroom volume at the moment so I'm not to fussed.)