New Tubes- Need Burn-In?


Hey guys- a question.

I just put a new matched quad of Electro Harmonix KT-88EH in my Cayin A-88T Integrated. I properly biased the amp, and after a couple of hours of warm up there is still a touch of "glare" or hardness evident.

I know these brand new tubes need time to burn in...how long a wait is reasonable before I decide whether the EH tubes are the ticket or not? Any tips on what to expect?

Thanks!
danlib1

Showing 1 response by mechans

Rumor has it that those GEC clone flat plate KT-88s from Shuguang are incredible. Is that really misguided??

BTW I am late to this thread, the answer is absolutely, you must burn in a new tube to get the best sound it has to offer. They burn in but do not take as much time as many as people say, for an input tube, in particular. They (inputs) will IMHO retain their sonic signature after at most 40hrs. I think people who say 200 hrs are just hearing things.
Output tubes are a different animal altogether they may need 100 hrs or more to settle into their final state they have been quiky in my amps, but they just seem to bounce around. They always seem to start thin and flesh out but even a matched quad will have a tube or two that takes more time and they can go through a really flat sounding period on the way, others flesh out right away.
Can't comment on the 6SN7s burn in every pair I own (may 10 pairs or more- I love tube rolling) is NOS and well burned in.