Jadis DA60 with Separate Preamp

Since the JJ E34L's voltage is little higher, will the DA60 adjust it correctly?

Yes, the DA60's cathode bias topology lets you run any EL34 / 6CA7 / KT77 / 6550 / KT88 / KT120 / KT150 tube by simply plugging it in.  It's completely mindless, and another one of the reasons the amp's a peach

Big KT-77 fan here the current reproduction Genalex Gold Lions are outstanding sounding tubes. Beat JJ 6ca7 fat bottles, PSvane Phillips Replicas, Svetlana, Tung Sol reproductions and a few more. Never tried the JJ EL34L and obviously my amp, a custom Deja Vu Audio PP stereo amp, is not a DA60. So as with most things YMMV.

@jond I may not feel quite as positive as you do about the Genalex KT77, but I love your choice in amplifiers!

I had a Deja Vu 45 / 2A3 PP amplifier, and along with my DA60, that was my all-time favorite.  As the collection of amps and speakers grew to an admittedly stupid level, I got the directive to liquidate.  Still remember that great tone and overall fantastic sound.  Aside from that, I came into my Quad ESL57 when Vu also got the directive to liquidate a bit from his director...

@trelja Thanks I love my amp and I've listened to a 45 pp amp from them it was fantastic but I thought a bit too detailed for my setup at the time. I went with the EL34 because it sounds good and it's cheap to retube.

Sounds like you have quite the collection I wish I had the space, and budget, for a collection of amps! And Quad ESL57's what a classic! One of the best things to happen to me as an audiophile is living 15 minutes from Vu's shop!
Cheers,
Jon