AUDIO RESEARCH D-76A


I am new to this trade so bare with me if I ask dum questions.
I have a AUDIO RESEARCH D-76A power amp that I been using for few months now. as you probably know this amp has the most tubes than any other tube amp that I can remember. the middle of the amp are four 12AX7. I notice that one of the 12AX7 [middle top] are not lighting up nor hot. so I had all the sockets replace but still no light nor hot. I was told that its normal. how could it be? will this de-grade my sound? please enlighten me. I will appreciate any advice. thanks
torogi
I'm not sure whats the deference between the line fuse in the screen fuse. all I know is that the D-76A has a line fuse. its rated at 6 A 250 V How do we find out weather its the right line fuse? surprisingly it never blew. I will try my third attempt tomorrow to call CALVIN at ARC to ask some of this questions.
Torogi, your last post implies that you are having a hard time getting through to Calvin. That is surprising because he is always available, at least when I call. I know he was on vacation last week, so perhaps he's catching up. If you can't get through to Calvin, then try Chris. Chris is the resident techie at ARC. I know that he supports the local ARC authorized repair guy where I live.

Sorry to sound like an old saw here, but I agree with Hifigeek and the others who have recommended that you ship the amp off to either ARC or an authorized local repair tech. I get the sense that you are trying to trouble shoot the amp yourself and unless you have a deep technical knowledge of electronics in general and ARC gear in particular, I think you're literally playing with fire, IMHO. If it was my amp, that's what I would do.
Your not going to get the answers you want talking to Calvin as he is the parts manager. Chris is the tech and he wont be able to really answer you because the unit is not in front of him. I can look and see what the fuse is supposed to be but that still wont solve your issue with the tube and the non standard ARC parts that were installed. It will have to go to someone for repair. You can send it to me or to ARC. Either way you will need a shipping carton if you don't have the original one for that amp. The boxes are not cheap but its the only way that amp will survive it's journey without damage.
I did finally talk to CALVIN today. the reason I cant get hold of him cause I think they are ahead of two hours than us + I can only call him during my break time at work. The fuse is 5 amps 250 volts not 6 amps I dont know if it will make any deference. I do agree both fo you 100% its not about replacing a few caps here and there I'll live this matter to the pro. I am being recommended by someone here in our area I am told he fixis vintage gears. he is currently working on a CLASSIC 60 ARC right now. to me thats a good news...this will save me shipping cost. I will be visit him sometimes this week. Worst come to worst I will send it to ARC or to HIFIGEEK.