humming choke on DRRI?

[chipaudette]

Hi All,

I've got a Fender Deluxe Reverb Reissue that I bought a couple of years ago and have been messing with heavily. Tonight I noticed that my amp was humming quite a bit...the hum was not coming through from the speaker...it was coming from the amp itself.

So, I unplugged the guitar, left the amp on, and looked around the back of the amp. Something back there was radiating a humming sound. After touching a few of the components, I found that the choke was vibrating (and humming) fairly strongly.

What does this mean? Do I need to replace the choke? Why would it go bad? Would my mods (all pre-amp related) have done something to cause this damage? What I'm saying is, is the vibrating choke the problem, or just a symptom of a problem somewhere else?

All advice welcome!

Chip

[tubeswell]

Hmmmmm, :-) if the choke was making a noise like that I'd guess that it was operating in some less-than-desirable way. What does the resistance measure across it (compared to what it is supposed to measure)? Is there a burning smell and smoke associated with the hum? And what do the voltages look like?

[metalangst]

The choke is a coil, coils have an electromagnetic field, loose coils hum. You might be able to put a shim between the coil and the core to keep it from vibrating. You can use a wood shaving, jam it in there if you find a loose spot.