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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
unclejeff
1,313 posts
 
I am a big-time Svetlana fan. a close second would be JJ (blue tube). Still, EH has lots of people who love them.
danlib1 OP
819 posts
 
Well, 2 for Svetlana KT-88's thus far! Would that be the "SED" units?
sogood51
2,157 posts
 
I installed new EH-KT88's in my Rogue amps (got them from Rogue)...they sounded good from the start, no glare at all?

Dave
newbee
4,793 posts
 
You must differentiate between SED's and Svetlana's.

Present day Svetlana's are nothing more than Sovteks in disguise. The really good Svetlana tubes are now called SED and they are made in St Petersburg. The logo on the tube is a 'flying C'. The change over took place several years ago so before buying "Svetlana" tubes investigate.

I use, on different amps, SED KT88's, 6550's, and EL34's and highly recommend them for their tone and ruggedness (I've never had one fail, yet).

I give any power tube 48 hours or so of break in before making a final judgment.
stevecham
3,340 posts
 
Ditto positive comments on the SEDs, especially the EL34s. Running a new quartet of these in a CJ CAV50 and they have all the extension and soundstaging I could ask for. Inner details and quiet backgrounds they do in spades, exactly what I was looking for. Likely one of the best brands of current issue EL34s for audio.
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