conrad-johnson supplies an all plastic screwdriver (just a thin plastic rod with the ends flattened) to use in biasing its power tubes. Would something like this solve the problem?
Upscale Audio -- Tubes and Reliability
Just wanted to get this out there for the benefit of A'gon members who own tube gear. All of my gear is ARC tube equipment.
I've been buying tubes from Kevin Deal - Upscale Audio for quite some time. Most recently, I bought a tube set for my amp. One of the KT-120 tubes didn't bias well. Kevin replaced the tube -- no questions asked!
In another case, the common carrier screwed up the delivery of a tube order. I left a VM for Kevin. He returned the call within 24 hours and made the situation right.
As an fyi, Upscale Audio burns in their tubes for 72 hours before testing and matching. Yes, there have been some glitches here and there, but so far Kevin has always come througth and made good.
Although I still buy some tubes from ARC, on rare occassion a few tubes blew shortly after purchase. Yes . . . ARC was 100% reliable in making good. Problem is ARC charges twice the price Upscale Audio charges.
Although I suppose one could argue that an advantage of buying from ARC is that if a tube goes bad and takes out some passives, ARC will pick up the tab. That may be true, but what good is that guarantee if you have to pack up your equipment and send it back to the factory.
In my case, I am fortunate because an ARC authorized tech lives near my house and makes house calls. True! As I reported before, one time a power tube blew and took out a bias resister. The tech came to my house and replaced the resister in about 45 minutes.
So for me, I guess the bottom line is this: if an UA tube goes bad and takes out some passives, is it worth the price savings to have the tech come out to fix the affected gear. So far, the price savings has justified the risk.
FWIW.
I've been buying tubes from Kevin Deal - Upscale Audio for quite some time. Most recently, I bought a tube set for my amp. One of the KT-120 tubes didn't bias well. Kevin replaced the tube -- no questions asked!
In another case, the common carrier screwed up the delivery of a tube order. I left a VM for Kevin. He returned the call within 24 hours and made the situation right.
As an fyi, Upscale Audio burns in their tubes for 72 hours before testing and matching. Yes, there have been some glitches here and there, but so far Kevin has always come througth and made good.
Although I still buy some tubes from ARC, on rare occassion a few tubes blew shortly after purchase. Yes . . . ARC was 100% reliable in making good. Problem is ARC charges twice the price Upscale Audio charges.
Although I suppose one could argue that an advantage of buying from ARC is that if a tube goes bad and takes out some passives, ARC will pick up the tab. That may be true, but what good is that guarantee if you have to pack up your equipment and send it back to the factory.
In my case, I am fortunate because an ARC authorized tech lives near my house and makes house calls. True! As I reported before, one time a power tube blew and took out a bias resister. The tech came to my house and replaced the resister in about 45 minutes.
So for me, I guess the bottom line is this: if an UA tube goes bad and takes out some passives, is it worth the price savings to have the tech come out to fix the affected gear. So far, the price savings has justified the risk.
FWIW.
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- 31 posts total
- 31 posts total