Bare Knuckle Pickups Forum

Forum Ringside => Guitars, Amps and Effects => Topic started by: Lew on March 24, 2010, 10:26:48 PM

Title: Amp gurus... UPDATED WITH GUT SHOTS
Post by: Lew on March 24, 2010, 10:26:48 PM
My Mesa Preamp is being a pain in the ass. The effects loop switch on the back has to be balanced in a very specific place (using a hairband) for it to have full volume otherwise it's vewy vewy quiet :/

Any obvious answers?

Ta
Title: Re: Amp gurus...
Post by: Oli on March 24, 2010, 10:58:26 PM
Sounds like it needs a new switch-- some switch cleaner (like DeoxIt) might temporarily fix the issue, but a new switch would be advisable :)
Title: Re: Amp gurus...
Post by: Lew on March 25, 2010, 09:42:27 AM
I'll get some spray and try it out and I'll swap the valves at the same time. I don't fancy swapping a switch over, though. It'll be like a rats nest inside the Mesa and I've got recovering alcoholic hands  :lol:
Title: Re: Amp gurus...
Post by: MrBump on March 25, 2010, 10:31:23 AM
What colour hairband?
Title: Re: Amp gurus...
Post by: HTH AMPS on March 25, 2010, 10:53:33 AM
What colour hairband?

I prefer yellow or pink for a livelier tone.
Title: Re: Amp gurus...
Post by: Lew on March 25, 2010, 12:35:36 PM
Black as I've been playing metal lately
Title: Re: Amp gurus... UPDATED WITH GUT SHOTS
Post by: Lew on April 04, 2010, 01:55:47 AM
I've just got round to popping it open, no wonder it's shorting its friggin' filthy in there especially the fx loop switch. Its got a grounding issue aswell, d'oh. 3 of the valves look like the original Mesa ones and there's a Ruby 12at7 and TAD e83cc. Needs a bit of a clean up and some new valves!

http://img242.imageshack.us/slideshow/webplayer.php?id=p4040001.jpg
Title: Re: Amp gurus... UPDATED WITH GUT SHOTS
Post by: Twinfan on April 04, 2010, 08:56:39 AM
That's filthy!!!

:lol:
Title: Re: Amp gurus... UPDATED WITH GUT SHOTS
Post by: hunter on April 04, 2010, 02:17:46 PM
What type preamp is it?
Title: Re: Amp gurus... UPDATED WITH GUT SHOTS
Post by: Lew on April 04, 2010, 04:24:38 PM
A Mesa Studio Pre - practically the preamp of a 2C+ with some value changes. It's dated Jan/89 on the board. No surprises Metallica used them in the early years, it nails the Ride The Lightning and Master Of Puppets style Mk gain.
Title: .
Post by: Lew on April 05, 2010, 04:47:06 PM
A clean up sortED the grounding and fx-loop issue! I replaced the TAD with one of the 20year old Mesas, sounds better - the TAD was waaaay to high gain and the lower gained Mesa seems to add a bunch of top end and definition over the newer TAD. I'm prob talking to myself :p
Title: Re: Amp gurus... UPDATED WITH GUT SHOTS
Post by: d1dsj on April 05, 2010, 06:25:35 PM
Cool that you're sorted! I had of those TAD pre amp tubes in V1 when I got my MK50 and it sounded bloody awful? I replaced just that one tube and the difference was night and day.
Title: Re: Amp gurus... UPDATED WITH GUT SHOTS
Post by: Lew on April 05, 2010, 06:54:19 PM
Yea, it was in V1 on the Mesa too.  The TAD sounds really poor compared to the original and ancient Mesa valve in V1!