I Have No Luck With Amps :-( More Buzzing

[FirstBassman]

As a fallback to my Crate V18 (with which I couldn't completely eliminate the rattling) I got a Bugera V5.

Well, the Bugera is doing the same thing. *

I isolated the source as the black slotted housing around the tube:






* The tech at the shop says it's because I keep buying cheap amplifiers.

[Maradona86]

I popped off the lame metal housing around the tubes in my Kustom '36 Coupe; haven't had a problem. Take it off, play with it and see how it does. I think they have those on these days more as a "safety feature" than anything.

[jefrs]

Most pre-amp valves have a shroud which is an earth shield. The Epi EVJ shrouds both bottles. That black slotted metal object is supposed to do the same thing, and it is supposed to keep the amp quiet. Check that the thing is connecting electrically to the chassis, the paint may be insulating it, use serrated star washers between it and the chassis.

[BigDaddyLH]

Originally Posted by jefrs

That black slotted metal object is supposed to do the same thing, and it is supposed to keep the amp quiet.

Ironic, given that it's rattling!

[tiktok]

Originally Posted by FirstBassman

[COLOR="Navy"]As a fallback to my Crate V18 (with which I couldn't completely eliminate the rattling) I got a Bugera V5.

Well, the Bugera is doing the same thing. *

I isolated the source as the black slotted housing around the tube:

If the cage is rattling, it's because it can move. Tighten the screws. If the screws are tightened all the way down, it's not the cage making the noise.

[celeste]

Originally Posted by tiktok

If the cage is rattling, it's because it can move. Tighten the screws. If the screws are tightened all the way down, it's not the cage making the noise.

The rattle could be coming from movement of the cage against itself, check the seams where is was bent up to form the box. Some RTV silicone caulk might be in order. If you do just remove it, and the tubes do not have retainers on them, think about installing them

[jefrs]

Screws loose, that's why to use anti-shake star washers between cage and deck, plus they usually ensure a good earthing connection. That thing is a very crude Faraday cage.

Looking at it, it is a bad design. The valves are too close together and are spitting out electrons into each other which can interfere: cause noise. A slip-on shroud with a flying lead attached to an earth point is the best solution but note some bottle stages don't like them and buzz loudly.

It is unlikely that a valve will fall out of a 5 watt amp without a retaining clip: they are not retained now.