Audio Research Vs115

Smatsui, not sure you laid out all the relevant facts about your resister problem. But based on what you did say, I surmise the VS-115 was under warranty since the resister problem occurred within one week of taking delivery from your dealer. When one of my bias resisters blew, my amp was still under warranty. ARC sent a tech to my house to fix it -- free of charge.

Bias resisters do double duty as fuses when a tube arcs. Tube arcing goes with the territory with tube amps. Now . . . as to engineering, I understand some manufacturers make self biasing amps with mini fuses for each power tube. Don't remember the models - sorry. OTOH, it is my understanding that ARC intentionally passed on that configuration to keep as much artifacts out of the circuit as possible.

I have heard of bias resisters making quite the racket when they do their job. Can't say I heard one took a ride out of the amp, but I guess sh*t happens.

If the problem you experienced was indeed as I surmised above, ARC would have fixed it in your house, the fix taking all of 30 to 40 mins. And I want to emphasize, power tubes are glitchy when new and have a tendency to arc during break in. If they do arc, something has to give or the circuits could fry.

Here's my bottom line: as soon as I get beyond the "tube break in nervosa period," I have little if any problems with my VS-115. And the double bottom line is that the amp sings.

I'm glad you found another fine amp to pick up the slack. But all of my electronic gear is ARC and except for the occasional pesky tube arc, I have no complaints. In contrast, after tweaking this and that, my rig is very musical and enjoyable.

If Gary (Hifigeek1), an ARC authorized tech, catches this thread, perhaps he can weigh in with his comments.

ARC tests their tubes at hard labor for 24 hrs. prior to putting them in your amp at the factory. No other tube reseller does this. Tubes are not perfect and they do fail. They warranty the tubes for 90 days and any damage it caused would be covered under warranty. The resistors are doing their job when they shatter. They are flameproof resistors. This is normal.

Bifwynne,

I'm not sure what relevant facts that I left out. My dealer would have given me a brand new replacement VS115 within one week if I wanted it. That is not the point. I did not want another VS115 after my experience. The KT120 tubes were fine. The center rear transformer also was humming loud enough that I could hear it in my listening position and it got pretty hot as well. When my dealer asked me if I wanted a replacement I told him that I did not want to wonder if this would happen again.

I think the VS115 is a fine sounding amp. I wouldn't have bought it in the first place if it wasn't. I just question its reliability.

Glad to hear that Paragon Sight & Sound took care of you. I have been in that shop a couple of times as I live in the Detroit area. And while I have not purchased anything from them it is reassuring to know that they support their customers and that I can feel comfortable should I ever purchase something from them.

Chuck

I've had my Jolida for a relatively short time compared to the tube guitar amps I've used since 1966. In all those years of constant gigging I never had a single incident of a tube failure taking out any other part of the amp...some tubes did fail here and there (extremely rare) but were replaced with zero damage anywhere else. ARCs issues, although seemingly often covered by warranty, seem strange to me...but then so much seems strange...NURSE...wheel me out of the sun!