Mesa Amp Repair Help

[jgcable]

Just picked up a late 80's Mesa Studio 22+ with matching cabinet.

Amp has very low output. When I plug the guitar into the effects return it has plenty of power so its not the power side thats bad. Its the preamp side.
I tried tapping the tubes and they don't rattle or make any noise. They all light up the same.

What should I be looking for ?

Would this be a sign of bad preamp tubes, filter caps or something like that?

Just need to know where to start looking.

[DonP]

Try the preamp tubes.

Filter caps impact the power amp mostly, increasing hum and reducing bass as they age.

[Cleveland Metal]

Hmmm.... You haven't swapped the preamp tubes out yet?

[Cygnus X1]

I am ready to say I can't help.
But preamp tubes sounds like a good plan.

I don't work on certain amps, Mesa being at the top 'o the list.
Sandwich construction generally pisses me off, and far too many proprietary components for my liking.

[tonemonster]

this is a long shot, but try this..... try turning the amp OFF, and spraying some electrical contact cleaner in the FX loop jacks and work them in and out with a plug on cord. let it dry and try it. this solved a similar problem on my laney a few years back. someone on the JCF advised me to try it. worked like a charm. its easy and work a try.

[Tmoran]

Just to let you know even if your preamp tubes are glowing they could still very well be malfunctioning. I would try replacing them first before anything else.

[Cygnus X1]

Just to let you know even if your preamp tubes are glowing they could still very well be malfunctioning. I would try replacing them first before anything else.

Heh.
I just gave that very advice on another forum earlier today.
True but have you been reading my mail?

[Chief_CrazyTalk]

What Tone said. I had a similar problem once with an amp (happened to be a Boogie too) and an effects unit. I'll bet it's just corrosion on the contact areas of the plugs.

All I did to solve the problem was work a plug in and out of the jack a few times and there it was. In fact if you google this you'll find it's a common problem, easily fixed.

[jgcable]

UPDATE>>>>
Amp is fixed. This was super simple. Dirty effects loop jacks. I plugged a volume pedal in the loop and the amp worked perfect but was intermittantly losing volume. I grabbed the contact cleaner and a few Q tips and cleaned out the send and return jacks and the amp works perfectly with no issues at all.
Thanks everybody!

[tonemonster]

Cool beans. or I guess its Cool Peeps around here.

[horns666]

Cool beans. or I guess its Cool Peeps around here.

Tone gives good Peep!!!!

He gave mind blowing advice..then he stopped short!

You want AMP REPAIR advice..I got yer back!

Many times we get old amps that haven't been played for a while...years perhaps. Cleaning out those loop holes is just the start..working them in and out with a plug. Yeah, keep doing that..for about 10-15 minutes. Then pull ALL the tubes out, and dust the chasis with a clean dry cloth...yeah that's it. Then start licking the preamp tubes. Start slowly, then faster..and harder. Then grab at the base and start sucking them clean. Don't break them..be careful. They have dangerous things in there. Once your done with the preamp tubes. Go for the bigger power amp tubes. I suggest putting some soft music on for this shit. Then grab the 6L6, EL34, 6550, KT88 ect..and open wide...go all the way down. Practice with the gag reflex muscles. I can get a matching quad of KT88s all the way down to the base and still eat a Peep.

When you're done with this. The tubes will look like new...spit shined. Dry thgem off with cloth and install them. Make sure they're seated well. Fire up the amp and be blown man. The amp never sounded happier. I mean..how would you feel and sound..right. A bond between player and gear is very personal & erotic thing. You please it, and it will please you.

Once the amp sounds great..now it's time to shine up that tolex!!! Three to four coats of fresh, hot, jizz will make any sad, used ghetto amp into a shiny boutique like muthafucka!!!

You're Welcome..ya fucks,

Bill Z Bub

[tonemonster]

I suggest putting some soft music on for this shit.

Kool and the gang?

[j2379]

informative and funny as hell....

[Shawn Lutz]

cool little amp. Congrats on getting it working again.

[jgcable]

cool little amp. Congrats on getting it working again.

Thanks Shawn, I'll tell you one thing. Its got a ton of gain and its gotta be the brightest sounding amp I have ever played through. Through the stock 1 x 12 its pearcing and not really in a good way. Hooking up the extension cab tones it down. Hooking it into a 4 x 12 and its perfect.
It sounds the best with the guitar volume rolled down to around 7 to bleed off some of the high end!
I always liked the Studio 22. This is my first plus.