Audio Research VSi60 integrated reliability?

I owned an ARC D125 that I bought used in the 90's that had an output tube internally short and the amp burst into flames rising up 6 inches above the amp which was destroyed. The dealer said he had 6 other customers with the same amp that used Chinese 6550's that also went down in flames. The driver and bias PC board was destroyed.

That's what I hear, postings that, no basically that's normal and part of the nature in owning tubes, and others that have experienced these issues themselves. Biasing an amp isn't much of an issue, just the thought of having to keep replacing resistors just to keep an amp running seems a bit much.

I admit to having an ARC bias (pun-LOL), but here is my experience. I've owned 2 ARC tube amps: the VS-110 and currently, the VS-115. Yes, it's true, on rare occassion (maybe twice), a power output tube arc'ed and took out a bias resister.

I'm fortunate to have an authorized ARC tech. service rep. who's shop is near my house and who also makes house calls. When my VS-115 blew a power tube and took out a bias resister, the tech came to my house and replaced the resister in 45 minutes. The repair was fully covered by the ARC warranty.

Look, tube amps on occassion blow power tubes and in some cases take out bias resisters. It goes with the territory. But I have never experienced an exploding amp problem. I may have read of one case on the Forum where an arc'ing tube did a lot of damage to an ARC amp, but not an explosion.

FWIW

Post script -- I replaced all the power tubes in my VS-115 with KT-120s. Aside from my sense that these tubes greatly improved the sound quality of my VS-115 as compared to the old 6550Cs, I understand that the KT-120s have a more robust build quality. So far, evrything is humming (pun - LOL). Again, FWIW.

Perhaps Gary (Hifigeek) can weigh in on his KT-120 experience. Gary is an ARC authorized service tech.

Well KT120's arc just like 6550's do. Possibly a bit less often. With regard to the Chinese 6550's of decades ago. Frankly they were awful tubes. But that was all that was available. They looked like the Tung Sol coke bottle 6550 but that's where the similarity ended. Their failure mode allowed the heater to work but not much else. The light was on but no one was home so to speak. I'm guessing in the D-125 more than one tube arced at the same time. The Chinese tubes liked to do that back then. The only Chinese tubes I will use even today are the EL-34 Treasures. That's it. Once bitten twice shy. Remember, at the time the Chinese were making the 6550, the Russians were still trying to gear up to make one. ARC helped the Russians make the 6550. I just wish they hadn't initially used the GE 6550 as their model. I always thought the Philips Sylvania 6550 was a much better tube. Initially the Russians were trying to change one of their stock beam pentodes into a 6550 but that failed miserably. The Russians never stopped making tubes. Remember, the Winged C 6550 was probably the 12 version of the Russian 6550. Trust me, I saw every single version of that tube over the years. Some good some not so good, and some without any getter flash at all. The KT-120 represents what is considered to be state of the art in Russia. The KT-120 looks to me to be a modified version of one of their radar tubes. It's a winner.