Is it time for a T.R. tune up?

[Thundermtn]

Hey everyone. So I bought my Triple Rec new in '01. Since then it's played a bunch of shows and been rolled, lugged, and grunted all over the place.



It always sounded great with just about zero knob tweaking and was a solid piece of gear. It is so solid and reliable I never really even thought about it. Just warmed it up and let it rip.

Now here I am nearly twenty-five years later and it's never had a problem, ever. Stock as a rock and probably on it's forth set of tubes. It probably didn't need that many sets but sometimes I'd hear what I guessed was AM radio playing and figured it was time for tubes if it had been three or four years. Later I learned the tubes were probably fine, but I know exactly ZERO about how the circut works, and it was always sounding good so I didn't mess with it much other than fresh tubes. Not broke, don't fix.

Anyway I'm here now to ask about if I should get it serviced since it's coming out of moth balls for about five years now. Also if there are any tricks or tips about getting it to sound even better that a leave well enough alone player may not have looked for. It was on loan for a couple years and the guy had it setup to not use the footswitch and it was sounding better than what I normally used back in the day. It sounded bigger and tighter with less hissing. What's the deal there? I only use the third channel so should I take it back to where he had it, IDK.

Near as I can tell, I think it's a relatively early C+ three Ch., that has in the neighborhood of five hundred hours of roaring full blast metal.

Thanks for any advice you might have.

 

[clutch71]

What a testament to Mesa Engineering and build quality. The picking up the radio stations could be tube related but is most likely bad power where you were plugged in at the time.

Not sure why it would sound different without the footswitch.

If the amp has sat for 5 years, you may want to power it up on a variac slowly so you do not slam the coupling capacitors that have sat for many years. Also speaking of coupling capacitors, it could not hurt to take the amp to a reputable tech and have them give it the once over and if they recommend changing the caps as some feel these have a shelf life of 25 to 30 years.

Good luck!

 

[user 41014]

The filter caps could take a few run throughs to shake the cobwebs off but 5 years doesn't seem that long.

 

[bandit2013]

I found that spiders do not conduct electricity all that good. They will make a home inside the jacks. I was puzzled why the Mark IV was not making any sound. Wolf Spider syndrome.

 

[Thundermtn]

Lol, I'll check those out. I always kept a cover on it but IDK that the borrower did so it's a little dusty. I'll run some de-ox on a q-tip and swab them out. Probably need to get a new fuse in the thing too, not sure if those really go bad though.

I think the setting was to bypass the footswitch totally and something to do with the loop knob. I'll ask him and find out, it was enough difference that I could tell instantly when I went back to my reference schematic settings. I always had a drawing of every setting in my gig bag to quickly get back to par if I loaned it to an opener and they went knob crazy. I didn't record his setting though, which wasn't that smart.

 

[bandit2013]

I know for a fact that the Mark III I bought in 1989 is still chugging away. I know the person I sold the amp too. everything in that amp is original except for the tubes. I did say it may need a capacitor replacement some day as it was 23 year old when I sold it. Not sure how much it gets played. I know I let it sit for 8 years without use due a slow healing injury that prevented me from playing the guitar (ripped tendons in the left elbow).

Not sure if doing a visual inspection of the Capacitors will do much, however if they had leaked out the electrolyte it would be visible, it would look like a clear goo or will have the appearance of being wet on the board. If you notice that, do not power it up, as the mess left behind may make things worse if you end up with any arcing. Not sure how loud one of those large caps would sound like if they explode. The small one's about a quarter inch in diameter of the radial or axial type sound like a gun shot or medium sized firecracker going off. I have experienced that on a few occasions but not with a guitar amp, usually during destructive over voltage testing on products as part of the development process. I doubt the caps in the amp will explode, but anything is possible.

Some amps may have capacitors that have been known to have issues. Somewhere in the forums it was mentioned issues with the brown caps. Not very descriptive as I do not believe the cap brand was mentioned. Perhaps the Rectifier Guru will comment on this topic. At 23 years of service, you are getting close to the point of replacement. Most of it is related to the thermals of the amp when it is running. How hot the capacitors may get from heat transfer of parts will shorten their life. Amps that suspend the tubes below the chassis will get hotter than the Recto style with the tubes above the chassis. Transformer heat will be there more so than the convective tube heat. Polarized capacitors should not get hot unless they are in an overvoltage state, installed backwards, or too much current ripple. They do have a finite internal resistance, sometimes called ESR. That may also contribute to heat dissipation. In most cases, the better caps may cost more but they have a very low ESR value, those are the ones that store high voltage for a long time after power was removed. There usually are bleed resistors in the circuit to discharge the caps. You may have a few years of service left.

I would assume that weak or bad power supply capacitors would result in excessive hum noise as they are no longer storing energy as effectively as they did when new. That excess ripple voltage in the power supply will be apparent in the sound quality of the amp. Even the clean channel will have distortion, hum or buzz that a preamp tube or power tube cannot fix. I personally never experienced a bad power capacitor with a tube amp yet.