Hi guys I'm new to this forum,
I have a 1997, fender twin amp, it's an all tube guitar amp, and when I take it out of standby, or simply turn it on without using standby, as soon as the amp starts to make sound, I get two little crackle and pops, then they go away,and the amp works and sounds great.i bought a whole new set of JJ Tubes for it and that did not stop this problem.i then tried installing all the old tubes back in the amp and again the same sound appears on startup.
Now I just recently started using this amp again.when I got it new in 1997 it did not do this,but when I finally started using it again.i found that it was making really loud cracking and popping sounds,as you would move the amp or tap on it.That ended up being a broke. Solder joint on the plug in the board that the plug from the little transformer plugs into the board.After reflows g the solder ,that problem went away
Now I have this small popping sound in startup,and the gain knob on the vintage drive channel gets scratchy and crackly and the. Goes away and cones back
I have a 1997, fender twin amp, it's an all tube guitar amp, and when I take it out of standby, or simply turn it on without using standby, as soon as the amp starts to make sound, I get two little crackle and pops, then they go away,and the amp works and sounds great.i bought a whole new set of JJ Tubes for it and that did not stop this problem.i then tried installing all the old tubes back in the amp and again the same sound appears on startup.
Now I just recently started using this amp again.when I got it new in 1997 it did not do this,but when I finally started using it again.i found that it was making really loud cracking and popping sounds,as you would move the amp or tap on it.That ended up being a broke. Solder joint on the plug in the board that the plug from the little transformer plugs into the board.After reflows g the solder ,that problem went away
Now I have this small popping sound in startup,and the gain knob on the vintage drive channel gets scratchy and crackly and the. Goes away and cones back
Clean the control and see if the problem goes away. If not, then either the control is bad,
or there's DC going through it, from a leaky capacitor, etc.
So can I just buy a cap kit for my amp and just alligator clip them in series with each remaining cap to see it it's fixed? Also is it harmful to my amp playing with it under these conditions? If the caps are in fact leaking? I also noticed that the green wire attached to the power tube socket right next to the speaker output in the chassis, and the green wire attached to the 12ax7 tube socket right next to the instrument output is making noise when tapped on through the speakers is this normal?
No, on the clipping of caps in parallel with the existing cap....
It could be that you have a bad solder joint somewhere. Years ago I had an amp that acted very similar. After much messing around I found a couple bad solder joints, re-soldered and all was fine.
Robert
It could be that you have a bad solder joint somewhere. Years ago I had an amp that acted very similar. After much messing around I found a couple bad solder joints, re-soldered and all was fine.
Robert
Ok so none of the wires in the chassis going to the tube socket should be microphones? It appears that some audio wires in the chassis are also and it's just bad solder joints that can cause this? I have been looking through the whole chassis and I don't see anymore broken solder joints.does one have to be brokento be bad or many just remelt it?
I found a beautiful Mesa boogie F-50 tube amp at. My local music store.for a week I've been going in and testing it out and playing it, searching to see if it did the same thing as my fender twin, as far as the very low static poppy sound when switching it from stand by and it did not.i just took it home today, plugged it in my room and when I switched the amp from stand by.....it is making the same exact sound my twin is now that it's home .....someone please help...is this interference ??
Does this occur when nothing is plugged into the amp?
If the answer is no then your problem is something in your input chain (cords, guitar, effects, etc...). Systematically add things one by one until you find the problem.
If the answer is yes, then try a different electrical circuit for power.
Robert
If the answer is no then your problem is something in your input chain (cords, guitar, effects, etc...). Systematically add things one by one until you find the problem.
If the answer is yes, then try a different electrical circuit for power.
Robert
Thank you for answering Robert.,,,this happens regardless of anything being plugged in.i was just in absolute shock yesterday however.As I mentioned I was in the store testing this mess boogie different times including. The night. Score I went to pick up the amp the next day and it did not make this low decibel staticky sound on startup and have. Even pulling my hairs out trying to fix this exact same sound on my fender twin.as soon as I brought the Mesa home I. The first sound I was greeted with was the same sound on startup as my twin..I talked to Mesa boogie as well as a separate Mesa boogie tech and they both said this is normal for tube amps?
I measured the voltage on all sockets at home and and it seems to be going between 124 volts
I measured the voltage on all sockets at home and and it seems to be going between 124 volts
Not sure that I would buy into the 'normal' for tube amps.... I have several Music Man tube amps currently and have no such issues. I also have owned several Fender tube amps with no issues. Two amps with the same issue to me sounds fishy..... like something external to the amp itself.
Tubes can make noise, but identical in two amps?????
You could try a powerline EMI filter..... I buy them from surplus electronic stores and build them into an electrical box / extension cord for use with most of my electronic toys. Search Corcom EMI Filters as there are many styles available.
Good Luck,
Robert
Tubes can make noise, but identical in two amps?????
You could try a powerline EMI filter..... I buy them from surplus electronic stores and build them into an electrical box / extension cord for use with most of my electronic toys. Search Corcom EMI Filters as there are many styles available.
Good Luck,
Robert
Ok I just discovered that if I power up either amp without using stand by, then in not greeted with the 2 faint pops on startup...however if I turn on standby and then turn stand by off I get the sputters for a second at startup
Also ... I found that when I first got my mesa boogie F50, I would get a rumbling sound at startup sometimes.i tapped on one of the power tubes and it was microphonic,and the rumble would repeat when tapped on.i took the tubes out and sprayed the pins with a little Deoxit DDothat seems to have oil in it, but I sprayed a tiny spurt on the power tube socket pins and replaced them in the amp.i waited 10 minutes and powers the amp on....when I took the amp out of stand by, the amp started rumbling and made this weird noise,and the fuse in the amp blew, and I smelled a burning kind of smell from the vents in back of the chassis....it was not a plastic type of burning smell but it was like something got hot.i replaced the power tubes with groove tube 6L6B and the fuse and the amp works great now and the smell is gone.can you tell me if I hurt anything? What do you think that smell was ?in sorry for the question but this amp is like new and in going crazy lol
Also ... I found that when I first got my mesa boogie F50, I would get a rumbling sound at startup sometimes.i tapped on one of the power tubes and it was microphonic,and the rumble would repeat when tapped on.i took the tubes out and sprayed the pins with a little Deoxit DDothat seems to have oil in it, but I sprayed a tiny spurt on the power tube socket pins and replaced them in the amp.i waited 10 minutes and powers the amp on....when I took the amp out of stand by, the amp started rumbling and made this weird noise,and the fuse in the amp blew, and I smelled a burning kind of smell from the vents in back of the chassis....it was not a plastic type of burning smell but it was like something got hot.i replaced the power tubes with groove tube 6L6B and the fuse and the amp works great now and the smell is gone.can you tell me if I hurt anything? What do you think that smell was ?in sorry for the question but this amp is like new and in going crazy lol
Then you don´t have a problem.
When you turn amp on, voltages take a few seconds to stabilize.
Until bypass caps reach stable voltage they will pass a little current, you need some current to charge caps to any DC level, Basic Physics 101, so you can´t complain about that.
Yes, that current through high value pots will make them scratch if you move them during that time.
When you turn voltage ON using the Standby switch, filter caps will take a definite time to charge, and meanwhile all preamp voltages will be varying.
Well, this is an entirely different problem.
No, you must measure DC voltage across Volume pot.
That will show whether cap is leaky or not.
That means nothing unless you post schematic showing what does "green wire" mean and what does it connect.
A couple pictures too.
You are doing the exact same as before: turning it on and immediately wiggling controls before voltage stabilize.
Just wait 1 minute after Standoff or first signs of life and it will be fine, as you said earlier.
If you don´t wait for 1 minute yes, it´s normal.
I guess Mesa Boogie knows something about Tube Amps and if they call this "normal" .... maybe it is after all.
For the first few seconds ... it´s normal.
As a side note, Music Man is not the best example: preamp is full Solid State and we are talking preamp noise here.
Standby may affect the lonely power tubes, but SS preamp is on as soon as you flip the power switch, WAY before power tubes warm up so they had ample time to stabilize.
Anmd even on other full Tube amps, it´s a non issue which is usually ignored because it´s insignificant and disappears by itself as soon as amp warms up and is actually used.
Car engines may sputter and cough when just started on a cold day, yet work flawlessly when they warm up ... no Mechanic will try to "solve" that "non problem".
Thank you soon much for that answer.. However .I am not wiggling the gain pot on startup....I was wiggling it after the amp has been on and was fully warmed up.The 2 little sputter sounds I am getting come when I turn the amp on.withe the stand by switch on...I let the amp warm up for 5 minutes and the turn off standby.and I get the 2 sputter sounds.
I found that if I power the amp on without using standby then I don't get the sputtering .....
I found that if I power the amp on without using standby then I don't get the sputtering .....
Hi Guys
This amp is 20-years old so all of its solder connections need to be redone. This fixes 90% of all problems in consumer electronics items.
Unfortunately, buying a whole new set of tubes is likely a waste of your money. As is a cap job. Tubes and caps present other symtpms that will come to light after the solder connections are fixed.
Electron flow erodes solder connections, so connections go "cold" over time and need to be redone. This is a major issue with surface-mounted equipment inasmuch as the solder connections are extremely small and there is little leeway for erosion before there are nuisance problems.
This amp is 20-years old so all of its solder connections need to be redone. This fixes 90% of all problems in consumer electronics items.
Unfortunately, buying a whole new set of tubes is likely a waste of your money. As is a cap job. Tubes and caps present other symtpms that will come to light after the solder connections are fixed.
Electron flow erodes solder connections, so connections go "cold" over time and need to be redone. This is a major issue with surface-mounted equipment inasmuch as the solder connections are extremely small and there is little leeway for erosion before there are nuisance problems.
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