@fsonicsmith response it very telling. ARC goes through many tubes in order to produce "matched" tubes. they probably re-sell they non passing tubes to other's. however, that says a lot about Audio Research and their level of expected excellence.
I made the mistake of purchasing tubes for my REF 250 amps from a "reputable" tube supplier in Southern California. They claimed that the tubes were matched and to specifications for the REF 250 amps. Not cheap, but much less than what Audio Research sells them for.
Well, approximately $3000 in repairs later, I learned my lesson. Tubes failed after they were correctly biased. I was sitting there and actually saw the tube go up spectacularly and the circuit board. It took out other parts of the circuit, not just resistors. It costs $3000 to repair.
If I had purchased the tubes from Audio Research directly, they would have repaired the amp free of charge if their supplied tubes caused the failure.
The authorized Audio Research repair center that did the repair work, told me to never purchase tubes from that supplier as although they claim that they are matched and to specification, they are not. They proceeded to test all the remaining tubes and showed me the readings vs Audio Research's standards for that amp. These brand new tubes weren't even close. They were way outside the acceptable range. Also, when the tubes arrived, they listed clearly on the labels what the specs were. That is so wrong.
I never contacted that tube supplier, because, what is the point? If anything they would have replaced that one tube. But no way would they have repaired the amp.
When I repair solid state amps and I have to purchase transistors, I typically have to purchase many just to find matching ones and also ones to match the "good ones" still in the amp. Often, I just replace all the transistors, just to be safe.
So, I can see why the costs of tubes from Audio Research is so much higher.
enjoy
I made the mistake of purchasing tubes for my REF 250 amps from a "reputable" tube supplier in Southern California. They claimed that the tubes were matched and to specifications for the REF 250 amps. Not cheap, but much less than what Audio Research sells them for.
Well, approximately $3000 in repairs later, I learned my lesson. Tubes failed after they were correctly biased. I was sitting there and actually saw the tube go up spectacularly and the circuit board. It took out other parts of the circuit, not just resistors. It costs $3000 to repair.
If I had purchased the tubes from Audio Research directly, they would have repaired the amp free of charge if their supplied tubes caused the failure.
The authorized Audio Research repair center that did the repair work, told me to never purchase tubes from that supplier as although they claim that they are matched and to specification, they are not. They proceeded to test all the remaining tubes and showed me the readings vs Audio Research's standards for that amp. These brand new tubes weren't even close. They were way outside the acceptable range. Also, when the tubes arrived, they listed clearly on the labels what the specs were. That is so wrong.
I never contacted that tube supplier, because, what is the point? If anything they would have replaced that one tube. But no way would they have repaired the amp.
When I repair solid state amps and I have to purchase transistors, I typically have to purchase many just to find matching ones and also ones to match the "good ones" still in the amp. Often, I just replace all the transistors, just to be safe.
So, I can see why the costs of tubes from Audio Research is so much higher.
enjoy