2266 Rattling issue is solved

[science]

I got in a Vintage Modern 2 x 12 in our shop and the player said it rattles when low notes are played in the clean voice; I played it and verified this. Pulled the chassis, tapped all the tubes, its not them- checked the cab for looseness. Noted the green plastic dress covers on the celestion speakers were glued on [hoped they were screwed on so i could remove them, as tapping on them gave a sharp plastic sound close to the rattling that rides the notes.

I used Shoe Goo [or plumber's goop, or in germany, E6000] and ran a bead around the covers to the speaker frames. Let it dry overnight. Played it again; Celestion- maybe put some damping material in those plastic bells, dudes. That was it.

[machinegun1]

Anyone else have this problem and have tried this fix?

cheers

[machinegun1]

I found the problem with my amp rattling at certain frequencies - its one of the power tubes (original Marshall ~ 4-5 years old so not too bad). Still sounds o.k but a bit annoying at semi low volume. If I touch the offending tube I can feel the vibration and it does get rid the rattle. But probably time for a new matched set I guess - I heard good things about the Penta brand so I will try those. Do you think I will need to re-bias?

[OyvindBjorgo]

Do you think I will need to re-bias?

Always when changing tubes, unless you are absolutely sure the new tubes are completely similar to the old ones. That would pretty much mean using a perfectly matched quad in a two-tube power amp (two at a time), or two perfectly matched quads matched with each other in a four-tube power amp.

[machinegun1]

thanks - I will definately do the bias