Amplifier service

This is starting to sound like a cold solder joint...
When the amp starts to act up, try wiggling the guitar's cable plug at the jack. Do the same for the speaker cable jack.

In a dark room, observe if all the tubes are glowing. There are some (very few) tubes, due to their construction, the glow of heating filaments is barely visible. Gently try to move the tubes around and listen for funny noises and look for a consistent glow.

Remember the wooden sticks? Orange sticks, chopsticks, skewers... Use one of these to poke around in the live amp. Start tapping with firm pressure every single wire connection... every resistor's, cap's, diode's, potentiometer's solder joint.
Tubes are glowing evenly. I tapped them like a snare drum. The problem repeated after all preamp tubes were changed. However, I have now removed the weber attenuator from the circuit. It had been on bypass, so I did not pay it much mind. It has now been 1/2 hour since I removed it and there has not been any cut out. I will not jump to conclusions this time though
 
:cry:Just the PITA multi-channel ones please....that Marshall looks to be a pain for diagnosing intermittent issues.
The little Peavey...Nooooooooo....don’t ditch that.
If I had anything else to add, I would/will.
I gget that. However, am I really getting anything from them when I only ever look for clean headroom and rarely raise the volume? Maybe solid saes or hybrids are right for me. If I sold them all, I could get a Kemper.
 
Tubes are glowing evenly. I tapped them like a snare drum. The problem repeated after all preamp tubes were changed. However, I have now removed the weber attenuator from the circuit. It had been on bypass, so I did not pay it much mind. It has now been 1/2 hour since I removed it and there has not been any cut out. I will not jump to conclusions this time though
See?.....many variables involved...
 
I gget that. However, am I really getting anything from them when I only ever look for clean headroom and rarely raise the volume? Maybe solid saes or hybrids are right for me. If I sold them all, I could get a Kemper.
I can dig that...you know that I have both SS&tube kicking around here...I’m not selling either right now....I have my eye on a new tube amp now...SS can have issues too.

Do I prefer one over the other? Yeah...Tube amps...simple, single channel, Tube amps...with a bit of clean headroom, preferably. But, to each his own. I dig my SS amps too.
 
Oh boy, this is getting weirder by the post! Besides the attenuator, there's extra speaker cables and their connections, too... :run:
But why would cables in tha back of the amp, not moving, cut out in this manner - starting agter 30 minutes and then only intermittently. Anyway, it is OK for now withou the attenuator.
 
But why would cables in tha back of the amp, not moving, cut out in this manner - starting agter 30 minutes and then only intermittently. Anyway, it is OK for now withou the attenuator.
Because anything that’s hooked up to the amp can/does have an effect on it. Pulling on the OT will induce symptoms like you described...the attenuator pulls on the OT...along with any other cables, or speakers. They are added variables.
 
@RVA
You do have a point there. I'm grabbing at straws at this point. But why would the attenuator in bypass mode be affecting it? Is the attenuators impedance matching the amps output impedance? Are you using dedicated speaker cables before and after the attenuator? Ooops, there I go again!
 
What does it sound like when it cuts out? Does volume goes completely to zero or just drops to ALMOST nothing? If almost, what does it sound like besides quieter? A quick video showing what it does would help. What makes it go back normal?
It crackles and diminishes. It may cut out completely, then crackle then go full volume. It does act like a bad cable actually
 
@RVA
You do have a point there. I'm grabbing at straws at this point. But why would the attenuator in bypass mode be affecting it? Is the attenuators impedance matching the amps output impedance? Are you using dedicated speaker cables before and after the attenuator? Ooops, there I go again!
Yes, they are speaker cables. It is a weber mass iii, which works with 4, mb 8 and 16 ohm in normal operation, no selector. I agree that it should be a non factor in bypass. This dod not happen when it was engaged, or at any time before this recent maintenance.

It is working ok so far with it disconnected. Fingers crossed!

I appreciate all the advice. Not
 
Please tell us you'r kidding!
About selling or the issue.

I am 100% serious about the tubes. You have a lot of homework to do and run the risk of killing yourself if you DIY your repairs, or get to lug it to a tech for $ 95 an hour. You have to buy tubes at $ 20 each. And why exactly? Because it is supposed to sound warmer than a new breed of SS amps, which really only happens at higher volumes, which I do not play at.

Everyone needs to experience tubes during their playing lifespan so they know what it has to offer. For my home playing needs, it is beyond unnecessary. I do not enjoy amp repairs like I do guitar repairs and mods. I am moving to the next phase of my life - enjoying my time by playing instead of fixing at the risk of electrocution.
 
About selling or the issue.

I am 100% serious about the tubes. You have a lot of homework to do and run the risk of killing yourself if you DIY your repairs, or get to lug it to a tech for $ 95 an hour. You have to buy tubes at $ 20 each. And why exactly? Because it is supposed to sound warmer than a new breed of SS amps, which really only happens at higher volumes, which I do not play at.

Everyone needs to experience tubes during their playing lifespan so they know what it has to offer. For my home playing needs, it is beyond unnecessary. I do not enjoy amp repairs like I do guitar repairs and mods. I am moving to the next phase of my life - enjoying my time by playing instead of fixing at the risk of electrocution.

I'm there with you, my friend.

I have played a lot of vintage amps - including JTM/JVM Marshalls, Vox, Fender, etc - and honestly, I cannot hear a difference between them and the new amps. The only difference - like you said - is enjoying playing. I have a JVM-410C that I never use. It's been up at Mom's for 20 years or so. I liked it, but I would sometimes get a bad tube from transport and try to swap tubes just before a show. My JTM30 Combo would overheat and shut down.

What amp do I see more in recording studios (both as house amp and as a rental) than any other??? Roland JC-120 hands down. Wonder why???

Guys laughed when we pulled up to Wasteland Weekend with a Line 6 Spider II HD-75 and Jackson 4X12's. After a lot of tube amps crapped out in the 100°+ weather and direct sunlight, they didn't laugh so hard. I loaned that rig to two different bands when their tub amps went down.

I know, "Line 6 sucks, it's made in China" and all that, but it worked and it held up for a 45 minute set in blowing sand and intense heat and no broken tubes from being banged around.

My owned-since-brand-new 1997 Marshall Valvestate seems to be an incrdibly solid amp. I replaced the original 1997 tube last year and didn't need to, I just figured it was a good idea. Heavy, Noisy, but never gave me any trouble. It spent 2 years on loan to a musical friend who toured Japan with it too, so I know it's been abused.

I have probably spent more time fiddling with my DSL40C than I have playing through it. I

I have bought 4 or 5 completely different sets of tubes, matched this, biased that, 5751/ECC83MG, ECC83S, JJ EC823, 7025 WA, KT-88, EL-34, a vinatge (expensive) set of Ken-Rad 12AX7's from the 1950's, a custom $149.00 WGS 50 Watt Reaper 55Hz, Special speaker cables, $220.00 for a Weber Attentuator, and it still doesn't blow me away.

My Marshall 2203 was a problem child too. All the headaches of tubes and not even a reverb feature.

I think I am an average guitarist, but I think my recorded tone - and always near-perfect tuning on a recording - are above average. If you listen to some of my tracsk, you will hear the same amplifier over and over again - Blackstar ID-Core 100watt Solid State.

Why???

It cost 4349 brand new, has a tone of built-in effects, has spatial (panning) delay feature, has a direct out and headphone jack, is dead quiet and sound good on tape. It causes me zero issues.

I don't mind working, swapping tubes, etc., but to be doing this much work - and still not having a tone I really feel confident with, what the hell am I doing this for???

To be able to say "I have a Tube Marshall?"

Seriously rethinking my main amplifier needs here....

To be totally honest....if a good cleaning will get rid of that buzzy/crackly quality on my VS265, it might just be the best amp I have for live work. British made, 65 watts RMS, line out to drive two cabinets, effects loop, easy to use footswitch (brand new and still in the original box) Eminence speakers.

Lot's to consider here.....
 
About selling or the issue.

I am 100% serious about the tubes. You have a lot of homework to do and run the risk of killing yourself if you DIY your repairs, or get to lug it to a tech for $ 95 an hour. You have to buy tubes at $ 20 each. And why exactly? Because it is supposed to sound warmer than a new breed of SS amps, which really only happens at higher volumes, which I do not play at.

Everyone needs to experience tubes during their playing lifespan so they know what it has to offer. For my home playing needs, it is beyond unnecessary. I do not enjoy amp repairs like I do guitar repairs and mods. I am moving to the next phase of my life - enjoying my time by playing instead of fixing at the risk of electrocution.

Hey, Man...

You should check out a Roland JC-40 or JC-120. In the studio, that's the amp we play through the most. I take my Blackstar ID-Core 100 with me a lot, because it's small and only weighs 22 pounds, but the Roland's are good amps and very user-friendly...

They come with casters, have an open back, twin speakers and none of the silly programmable nonsense.
 
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