jcm 800 is buzzing again for god sake

[bobbyvasco]

I'm not convinced; have a listen through headphones or a good stereo monitor setup. The phone appears to be stereo mic'ing, and the buzz doesn't quite follow the 'direction of the guitar tone'. I'd say it's something auxiliary - not in the recording loop itself.

of course....it is much much worse in reality because the phone reduced the vbibration a lot.... the buzz on guitar is not even heard in the amp...

 

[bobbyvasco]

ok I hook the guitar on looper and played the note that is vibratiing.....
i separated the head and speaker by 2 meters.....
seems like the annoying vibration is coming from the inside the speaker....
i even took the handles off again....noting changed...
and unplugged the reverb tank on jcm 800 that one was still vibratiing even though I put the dampers on the screws.....
I cant locate this annoying vibration....
i touched the cones on the speakers speakers if they are loose ...I cant fucking locate it.....

 

[PelliX]

ok I hook the guitar on looper and played the note that is vibratiing.....
i separated the head and speaker by 2 meters.....
seems like the annoying vibration is coming from the inside the speaker....
i even took the handles off again....noting changed...
and unplugged the reverb tank on jcm 800 that one was still vibratiing even though I put the dampers on the screws.....
I cant locate this annoying vibration....
i touched the cones on the speakers speakers if they are loose ...I cant fucking locate it.....

How about the feet? Put the cab on its side for shits and giggles.

 

[bobbyvasco]

How about the feet? Put the cab on its side for shits and giggles.

i did that also touched the feet and nothing was loose......i fucking sold my old cab because of vibrations...the new one was fine for a while and now here we go again.....

 

[PelliX]

i did that also touched the feet and nothing was loose......i fucking sold my old cab because of vibrations...the new one was fine for a while and now here we go again.....

How sure are you that's the cab, not the floor or something silly?

 

[anitoli]

Have you tightened the speaker mounting screws? Tightened any other screw in assembly points?

 

[bobbyvasco]

ok i tried to locate the vibration again.....i put it in stereo again, and removed the handles on both sides....and in right stereo mode it is much worse then in left stereo mode....
i put a hand on the top right speaker cone and seems to me that is creating that annoying distortion......even though there is still a little bit of annoying distortion on the left side though, but much less when in left stero mode
i tried to see is the speaker is loose...it is not....i tightened all the screws a while ago, with no results.....
so is it the cone, or something in front of the speaker?

 

[KraftyBob]

Try a different speaker cab. I worked on a Blues DeVille 4x10 that had a vibration on certain notes. I checked to make sure all the screws in the combo were tight, etc. Turns out one of the speakers was shot. Bought a replacement and back to normal.

 

[bobbyvasco]

honestly with Marshall crap...you need a live in repair guy...... besides a live-in maid...they could live in the same fucking room...probably have babies sooner or later just to maintain your marshall crap....
how could the speaker blow?

 

[anitoli]

how could the speaker blow?

Prolly played some country at some point........

 

[PelliX]

honestly with Marshall crap...you need a live in repair guy...... besides a live-in maid...

Marshall only got big by selling extended warranty and service contracts. Eh...

how could the speaker blow?

Being attached to a crackling 1959 with a faulty valve.

 

[bobbyvasco]

so i switched to my jvm 410 after a year and the speaker buzzing is gone......i really do not understand this....is the jcm 800 causing the vibration inside the signal already? Because the sound right now is horrid the speaker really sounds like it is broken...but with jvm in all channels I do not hear anything major....wtf is going on here

 

[RLW59]

Crazy idea: maybe try swapping out the PI? (Yes, most people who spend time on amp forums know what a PI is.)

 

[bobbyvasco]

Crazy idea: maybe try swapping out the PI? (Yes, most people who spend time on amp forums know what a PI is.)

you mean just the PI? or all the tubes?

 

[PelliX]

Well, this is a bit of an old trick we used to use back in the day, ya know. To balance the negative impulses, you need positively charged particles in the circuit. Minus plus minus equal plus, right. Put this on loop through the cab for about an hour.



It may not resolve the problem indefinitely, but after about 30-40 minutes you won't care about the buzz and your 'bigot neighbor' will have had his fair share.

 

[Marcomel79]

you mean just the PI? or all the tubes?

He means just the PI

 

[Kuga]

ok I hook the guitar on looper and played the note that is vibratiing.....
i separated the head and speaker by 2 meters.....
seems like the annoying vibration is coming from the inside the speaker....
i even took the handles off again....noting changed...
and unplugged the reverb tank on jcm 800 that one was still vibratiing even though I put the dampers on the screws.....
I cant locate this annoying vibration....
i touched the cones on the speakers speakers if they are loose ...I cant fucking locate it.....

Disasembly back panel and check all screws from inside. The ones that screw the front panel. They have to be strong. Good luck.

 

[Kuga]

Could be the amp. if everything is tight on speaker cab. When I Installed a serial FX loop on a Madamp J5MKI different speakers made a buzz playing the A note with 6th string. Always I check the amp step by step when I'm doing something on It. It was the FX loop shielded cable. I don't know why. I replaced this 10cm cable for other one. Fixed It. I used same type cable. Maybe a bit longer the new one. Shield connected to ground. Again I don't know why can create buzz a cable.

 

[PelliX]

@Kuga did you listen to the clip he posted earlier? He outlined that he'd removed the head from the cab physically, too. Chances are it's the cab or (my guess) something else that's vibrating in sympathy.

@bobbyvasco Sell me the cab. I will take care of it. If you want, I'll take the 1959 off your hands, too. It's probably crackling because it's broken beyond repair. The flux capacitor's gyroscopic particles will be depleted, and we know what that means. I'll give you 500 + shipping, you keep the valves.

 

[Ramhead]

you keep the valves.

But.. the valves are original, you need those