+1 @larryi agree, and most don't even realize they've had a voltage spike occur until one of the components isn't working and start troubleshooting backwards from there.
Life of KT 150 Tubes
Auris audio Mono Block -Forte 150 uses Two KT150 for power output for each monos, Very strangely a both amps popped the KT 150 same time. I can vouch it had less than 1000 hours in 2 years as I have NAIM NAC 252/NAP 300 in the same room. I tested the tubes and one is 100% dead and the rest have very marginal life. With great difficulty I have ordered four new tubes. Would any of you know why this would have happened, in the sense bath amps not working at the same time? I am trying to get hold of Auris in Serbia. Even a good Valve tech will not open the unit without schematics and Auris wouldn’t provide one. I am in Canada. There are 2 authorized service center in the US. When crated both amp weighs 94 Kgs.Not easy to ship. I tried with a borrowed set of TUBES , there is no Biasing at all,mA reads 0, but there is signal coming in and VU display lights up.
Lesson learnt well not to buy equipment that is hard to service. I bought this even before there was a dealer in canada. I tried contacting the distributor Motet in Toronto. They are telling me to contact Dealer in Edmonton 300Km away. He never sold me the unit, why would he have any interest if he didn’t make any money on this unit? The unit cost $16,800 USD. Any advise what I should do?
Showing 5 responses by decooney
Opinions will vary - and while it may not be related, for reference I run my KT150s at 45-50ma, designer says I can go up to 60ma with no issue yet I have tried them as low as 40ma and they still sound pretty good. Currently running KT120s at 50ma too, good enough, no need to burn out tubes prematurely if you don't need to. You'll see manufacturers reporting different life values between 2000-3000hrs for KT150s, and half the for KT120s and yet that can change for the better if you are not running the bias up too much. Ask your amp mfg/builder again on bias too. |
That might have been true 4-5 years ago. Not so much any more. Its possible OP got hands on some early gen old stock 150s with the amp from 4+ years ago. Just a hunch. They had gotten it sorted out past few years. Again - buying tubes from a reputable tube dealer/reseller matters. Buy from someone with proper test equipment who actually stress tests, listens for noise, and matches output tubes before sending them out. Now fast-forward there are other sourcing problems of course. Hoping at least 1-2 other new builders step up with even better KT120, KT150, KT170 gen tubes. They could sell the crap out of them if they did it right. . |
How was the trip to the dealer in Edmonton back on 4/17 - were they of any help, any luck? Curios to learn more about what compromised your KT150s. Thx. |