MK III Blue Stripe Problems

[tyler_89vision]

Hi there I just bought a Limited Edition MK III fully loaded from 1988 and when I got it, it magically had problems that didn't show up in its sales description. The amp sounds great, sometimes. Main problem is, the R2 channel does not even work. When in R1 and hit the switch to get to R2, the amp goes pretty much dead, nothing comes out of it. When I'm in Lead mode and hit R2, it gives real quite thin distortion. The foot switch does not even light up when I hit it. To test if it was the foot switch, I plugged my R1 to Lead switch in the R2 slot, and it didn't light up when I hit it either, so it must not be the foot switch. Also it will sometimes make horrible buzzing (even in R1) that is VERY noticeable, even when playing. Sometimes it does, sometimes it doesn't. Every now and then, I can also hear what sounds like glass rattling within the amp, primarily in R1 when I hit my low E string. I have tried replacing two of the power tubes and switching them out, nothing. Also did the same thing with preamp tubes, nothing. I'm not sure whats going on with it, this thing is very unpredictable, but I love it, its really nice and I want in to work as it should. Any advice? I am on a budget (I spent all my money on the **** amp), and I do not live near an authorized repair station.

Thanks,

Tyler

 

[camsna]

Get a hold of Monsta-Tone on this board. Send him a PM.

He overhauled my Blue Stripe for me and it went from less-than-inspiring to the best amp I've ever owned. Those problems sound like a combination of the following:

1) Tubes. Get a WHOLE new set. I got mine from Dougstubes.com
2) Filter caps
3) LDRs

Anyhow. I shipped him my chassis (he's in NM) and he made it wonderful. There are also some mods he did. But, in the opinion of every Mk III owner I've heard from, the R2 volume mod is a MUST. The way Monsta-Tone did it for me was that he set the Direct Out to a fixed level and used the Direct Out knob spot as a volume control for R2. Made the amp MUCH more usable.

He also did an adjustable bias mod for me. Allows you to use any tubes you want and bias them nice 'n' warm!

Hit him up. Tell him Cam sent you. He was more than reasonable and I'm pleased with his work!

 

[CoG]

Too late to remind you to try used amps before you buy them, eh?

First, get a full set of new tubes, power and preamp. Sorry man, but this is part of the budget when you buy a used amp. Your R2 problems sound like they could be a bad tube in V2.

Second, do the channels switch properly if you use the pull knobs?