Vacuum tube ! And Warnings


To all out there who have Vacuum tube Amplifiers .
my friend just bought his first tube amp , it came with EL34 power tubes he wanted to get a bit more punch . He ordered on EBay  6550s I told him I would assist in fine tuning the bias.
he plugged them in we turned it on and a huge transient goes through one of the speakers and a surge through one tube . I shut it down waited 5 minutes then turn it on bias has a built in meter ,I checked they were over 90 +milliamperes maxed the meter. should be around 50. I removed them , he is sending back.the story here is many Ebay sellers don’t even test them they just get them from Russia and state as a match quad ,and runin for 24 hours . Never buy from anyone that doesnot  personally check them .
viva tubes, and upscale Audio are good , Jim mc Shane is good.
for vintage tubes, Brent Jesse recording, and Vintage tube services   I recommend. 
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Showing 1 response by big_greg

Saying that every tube seller on ebay is bad is a bit of a head scratcher. I bought two matched quads of KT120’s back in October from ebay for my Rogue Audio monoblocks and no issues whatsoever.

I just biased my amps today and the tubes in one amp had not drifted at all, and in the other amp, a couple of tubes were just a hair off. That particular seller has about 19000 transactions and 100% feedback. I would keep an eye on those numbers when considering making ANY purchase from ebay.

I’ve bought tubes from Brent Jessee and a couple have had had issues. That doesn’t make him a bad seller. He arranged to get me new ones pronto and was super helpful when I had questions about the best tubes for my gear, listening preferences, and budget. I recommend him highly.

I’ve also had issues with Sophia Electric tubes. Same thing, they got me new ones quickly and were easy to deal with. I’d also recommend them.

I don’t know how the other seller would have responded if I had problems, since I haven’t.

Exercise common sense and good judgment when buying from ebay, the same as you should when making any online purchase. Don’t lump all sellers into one bucket because of a couple of bad ones.