capacitor upgrades
- Thread starter esandes
- Start date
Chickenwings
Alnico 6/8
Re: capacitor upgrades
have you done the toobs first?
26 years is definitely time for new electrolytics tho.
have you done the toobs first?
26 years is definitely time for new electrolytics tho.
the guy who invented fire
Fuzzy. Guitars
Re: capacitor upgrades
What do you mean "acting up"?
What else has been done to the amp over the years?
If you mean filter caps just stick with what works...brand is not a big deal in filter caps as long as you buy something quality (Sprague, F&T, etc).
What do you mean "acting up"?
What else has been done to the amp over the years?
If you mean filter caps just stick with what works...brand is not a big deal in filter caps as long as you buy something quality (Sprague, F&T, etc).
Re: capacitor upgrades
yes the tubes were upgraded. the pre-amp tubes i replaced were even original marshall branded tubes.
by acting up i mean a nasty feedback in high gain channel 1 if i'm within 5 feet of the amp while the volume is at 1-2 and up. this is a 1987x. plus when i stop and turn the volume way down, the hiss from the amp is intermittent in intensity. then the intermittent his stabilizes to a constant hiss. when i turn up the volume from room level to stage level there is that old-stereo-type nasty sound that happens when you turn the volume knob.
the amp is bone stock. i plan to bring it to a reputable amp mechanic for a complete cap replacement.
yes the tubes were upgraded. the pre-amp tubes i replaced were even original marshall branded tubes.
by acting up i mean a nasty feedback in high gain channel 1 if i'm within 5 feet of the amp while the volume is at 1-2 and up. this is a 1987x. plus when i stop and turn the volume way down, the hiss from the amp is intermittent in intensity. then the intermittent his stabilizes to a constant hiss. when i turn up the volume from room level to stage level there is that old-stereo-type nasty sound that happens when you turn the volume knob.
the amp is bone stock. i plan to bring it to a reputable amp mechanic for a complete cap replacement.
the guy who invented fire
Fuzzy. Guitars
Re: capacitor upgrades
Caps have nothing to do with gain hiss or feedback.
Being a 26 year old Marshall it does more than likely need a cap job but even with a full cap job you'll still be having the issues you described above.
Caps have nothing to do with gain hiss or feedback.
Being a 26 year old Marshall it does more than likely need a cap job but even with a full cap job you'll still be having the issues you described above.
Chickenwings
Alnico 6/8
Re: capacitor upgrades
Tubes can potentially go from good to dead at any time and the vast majority of amp problems can usually be tracked down to one or more tubes (i'm guessing a preamp tube) going bad in one way or another.
Swapping preamp fresh preamp tubes in one at a time is a good way of eliminating that from your problems and requires no special skills or rebiasing. If that doesnt track down the culprit, then do the power tubes. Even that is something you can do with no special skills. If that does not fix the problem, send it to the tech for some diagnostics.
It really is due for new caps at its age, but you need to eliminate the probability of a dodgy preamp tube first.
If, after you sent it to the tech that it happens that the problem was not in the tubes, at least you now have a strong set of new tubes and can keep your older set as spares for gigs.
I mean - have you replaced the tubes since it started acting up? HOw long ago did you do that?
Tubes can potentially go from good to dead at any time and the vast majority of amp problems can usually be tracked down to one or more tubes (i'm guessing a preamp tube) going bad in one way or another.
Swapping preamp fresh preamp tubes in one at a time is a good way of eliminating that from your problems and requires no special skills or rebiasing. If that doesnt track down the culprit, then do the power tubes. Even that is something you can do with no special skills. If that does not fix the problem, send it to the tech for some diagnostics.
It really is due for new caps at its age, but you need to eliminate the probability of a dodgy preamp tube first.
If, after you sent it to the tech that it happens that the problem was not in the tubes, at least you now have a strong set of new tubes and can keep your older set as spares for gigs.
the guy who invented fire
Fuzzy. Guitars
Re: capacitor upgrades
I can't tell you any more than I have w/o hearing the amp myself...
What uncertainty are you sensing??
I can't tell you any more than I have w/o hearing the amp myself...
What uncertainty are you sensing??
ratherdashing
Kablamminator
Re: capacitor upgrades
Yeah, for sure. Amp troubleshooting via the Internet is super easy. People should be able to just tell you exactly which component in the amp to swap based on a short description of the problem. I mean, I knew right away when you said "acting up" that it definitely needed a cap job.
Yeah, for sure. Amp troubleshooting via the Internet is super easy. People should be able to just tell you exactly which component in the amp to swap based on a short description of the problem. I mean, I knew right away when you said "acting up" that it definitely needed a cap job.
Chickenwings
Alnico 6/8
Re: capacitor upgrades
I don't think i can make this any clearer or any more cut and dry:
Check your friggin tubes before asking a forum for advice then criticizing us for not having mental telepathy and being able to diagnose an electrical circuit problem via the internet
Once the tubes have been eliminated as the source of your problem, get new caps anyway cos your amp is old.
Do you get it or are you still uncertain?
:butkick:
I don't think i can make this any clearer or any more cut and dry:
Check your friggin tubes before asking a forum for advice then criticizing us for not having mental telepathy and being able to diagnose an electrical circuit problem via the internet
Once the tubes have been eliminated as the source of your problem, get new caps anyway cos your amp is old.
Do you get it or are you still uncertain?
:butkick:
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Edgecrusher
Well-known member
Re: capacitor upgrades
Dont spit the dummy... Tubes and Caps are internet catch all advice when people should actually ask a tech. No need to be a knob
Dont spit the dummy... Tubes and Caps are internet catch all advice when people should actually ask a tech. No need to be a knob
Chickenwings
Alnico 6/8
Re: capacitor upgrades
Edge...i'm not being a knob. I told him this stuff AND told him to take it to a tech. Its not my fault if the OP doesn't read the advice he is given. Myself and others have spent time to help him out with this. There is no uncertainty except from the OP. If he read all the posts in this thread he will find there is no incongruity whatsoever.
Edge...i'm not being a knob. I told him this stuff AND told him to take it to a tech. Its not my fault if the OP doesn't read the advice he is given. Myself and others have spent time to help him out with this. There is no uncertainty except from the OP. If he read all the posts in this thread he will find there is no incongruity whatsoever.
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Re: capacitor upgrades
Do you not love it when guys get pissed because WE cannot fix THEIR "cut and dry" problems, from thousands of miles away.?
best
Do you not love it when guys get pissed because WE cannot fix THEIR "cut and dry" problems, from thousands of miles away.?
best
woemoejack
Active member
Re: capacitor upgrades
This is the best thing you can do for it. Get it into the hands of someone competent to diagnose the problem before replacing a bunch of parts that may or may not fix the issue.
This is the best thing you can do for it. Get it into the hands of someone competent to diagnose the problem before replacing a bunch of parts that may or may not fix the issue.
Re: capacitor upgrades
i just finished a two hour session with the amp and for the first hour i was nursing it around 1-2 volume. i checked to see if it was still crackling intermittently with low guitar volume and it was.
so i just dimed every single knob on the amp and let loose for an hour. all of the problems went away. the amp needs a good warming. what would explain the mis-behavior when it's babied?
i just finished a two hour session with the amp and for the first hour i was nursing it around 1-2 volume. i checked to see if it was still crackling intermittently with low guitar volume and it was.
so i just dimed every single knob on the amp and let loose for an hour. all of the problems went away. the amp needs a good warming. what would explain the mis-behavior when it's babied?
Kamanda~SD
New member
Re: capacitor upgrades
1) Just FYI, don't worry about 'original marshall branded tubes' they are just RE-branded anyway. Experiment and dont fuss over that, no one cares how original or close to stock the tubes are
2) Take it to a tech if you don't know what you are even looking for. Seriously, save the headaches/further damage. Its probably going to be $50 just to open it up then labour/ parts from there. Sure beats spending $1000 + on a new amp
3) What model is it? That bit of info can always help (common problems etc.)
1) Just FYI, don't worry about 'original marshall branded tubes' they are just RE-branded anyway. Experiment and dont fuss over that, no one cares how original or close to stock the tubes are
2) Take it to a tech if you don't know what you are even looking for. Seriously, save the headaches/further damage. Its probably going to be $50 just to open it up then labour/ parts from there. Sure beats spending $1000 + on a new amp
3) What model is it? That bit of info can always help (common problems etc.)
Re: capacitor upgrades
1) i don't care either. don't get hung up on that. it's not the issue, clearly.
2) for a forum with very vocal "experts" you'd think i'd have a half-decent diagnosis. the best reply/help was actually PM'd to me. "get new tubes!" drrrr..
3) 1987x, as per post #7.
1) i don't care either. don't get hung up on that. it's not the issue, clearly.
2) for a forum with very vocal "experts" you'd think i'd have a half-decent diagnosis. the best reply/help was actually PM'd to me. "get new tubes!" drrrr..
3) 1987x, as per post #7.
GoldenVulture
Braindeadologist
Re: capacitor upgrades
Possibly your caps taking ages to build up enough charge to remain constant in delivering power.
Also worn pots [ Vol, etc] Try a bit of contact cleaner in them. [ Turn off the amp before you do ].
Possibly your caps taking ages to build up enough charge to remain constant in delivering power.
Also worn pots [ Vol, etc] Try a bit of contact cleaner in them. [ Turn off the amp before you do ].
the guy who invented fire
Fuzzy. Guitars
Re: capacitor upgrades
1-How do you know that tubes are not the issue? Did you test them?
2-No one here that I know of here is claiming to be a tube amp expert and even if someone is/was on one, no matter how good can trouble shoot an amp that is in Canada from in front of their computer based on "my amp is acting up".
I am by no means an expert but in my experience 98% of noise with tube amps can almost always be traced back to a bad tube.
While we're at it, and I believe I said this earlier in this thread...a 26 year old tube amp more than likely needs a full cap job...not always but more than likely.
The fact that the amp in your own words makes noise when used at low volumes but not at high volumes tells me that more than likely the noise is always there but when the amp is cranked you can't tell it.
If you own a car it is expected once in a while that you'll have to take it to the shop for minor repairs and general upkeep...a tube amp is no difference...
You wouldn't drive a 26 year old car w/o oil changes, new belts, hoses, etc...
Take the amp to a shop and have it looked at...reading on the internet that your 26 year old Marshall is acting up when played at low volumes tells me (or anybody else reading the post) little to nothing.
Sorry we couldn't be more help.
1-How do you know that tubes are not the issue? Did you test them?
2-No one here that I know of here is claiming to be a tube amp expert and even if someone is/was on one, no matter how good can trouble shoot an amp that is in Canada from in front of their computer based on "my amp is acting up".
I am by no means an expert but in my experience 98% of noise with tube amps can almost always be traced back to a bad tube.
While we're at it, and I believe I said this earlier in this thread...a 26 year old tube amp more than likely needs a full cap job...not always but more than likely.
The fact that the amp in your own words makes noise when used at low volumes but not at high volumes tells me that more than likely the noise is always there but when the amp is cranked you can't tell it.
If you own a car it is expected once in a while that you'll have to take it to the shop for minor repairs and general upkeep...a tube amp is no difference...
You wouldn't drive a 26 year old car w/o oil changes, new belts, hoses, etc...
Take the amp to a shop and have it looked at...reading on the internet that your 26 year old Marshall is acting up when played at low volumes tells me (or anybody else reading the post) little to nothing.
Sorry we couldn't be more help.
