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so like the title says, i've got a transformer that has an audible buzz coming from it, its definately mechanical, i can feel it coming out of the bell housing when i touch it,, its strong enough to vibrate the chassis, and it bleeds into the signal when im not touching the strings or bridge, and it also shows up with high gain noise as well...

would fender somehow sell me another transformer through some repair department? i tried calling fmic consumer line, but didnt feel like sitting on hold for a few hours, sent an email and got a bounceback stating some sort of huge backlog overload of emails, and they appreciate my email and will get to me when they can

so what can i do here, Im not really on the level comfortable enough to replace my tranny... and its pcb mounted board with nice couplers instead of solder tags, so its not like i can get a direct drop in for it at the local chinese electronics supplies shops here in vancouver. I've heard of tightening the bell, relaquering it, stuffing duct tape inside the bell housing, putting wooden wedges in bell, and even hitting it with a ball peen to cave the bell and tighten it up, GENTLY TAP though, not fricken wail on it. Are these viable options, anyone else had this happen to a tranny? I've also read this has to do with the lorentz something something effect (the name eludes me just this minute) but basically the magnetic forces, well, force the coils to vibrate and create that humming.


anyhow, any help or insight would be greatly appreciated guys!

so its not like i can get a direct drop in for it at the local chinese electronics supplies shops here in vancouver

You can replace your broken transformer with any transformer which fit the specifications of the ouput stage. You can even contact the factory in China which made the fender amp to get a transformer if they sell it for unity (big doubts about that) .

would fender somehow sell me another transformer through some repair department?

I think big corporations don't sell parts to the customers but to their "repair service" . If you want a perfect match I think you have to contact one of those.

But as said above you can put another tranisformer even a "better" one if the chassis has the room to do it .

here's the schematic :
https://docs.google.com/file/d/0B94M9ut ... edit?pli=1

Q?
Is this your fist experience with a Valve Amp?
My thoughts are go get a professional opinion before you outlay money on something that may not be the actual problem.

All transformers vibrate to some extent the more current draw the greater this effect.
Just stand next to a 600 Amp industrial welder and you will catch on fast,, at idle small vibration,, start welding and it buzzes like crazy.

My mate purchased his first Valve Amp only 2 years back (a Fender Pro Jnr) and his first comment was;
Gee are they supposed to hum like that?
My Answer; So welcome to the wonderful world of heater hum.

In other words the buzz maybe from heaters and the vibration may have little to do with the audible buzz/hum coming from the speaker.

Yes it is possible the Transformer is badly made and if the windings are vibrating badly it won't last long as the loose winding will break soon enough.

After hearing the quite loud buzz from my mates little fender then obviously fender have not learnt much about design in all those years.

I tend to think heater hum is a more likely suspect.
Hope it helps.
phil.

hey, just wanted to update you all..... turns out the thing i read regarding the lorentz effect (or w/e its called) and caving the bell housing with a hammer to tighten it up and apply pressure to the tranny core. well, it friggen worked!

now im not sure if its going to work for everyone with an issue like this, but holy hell. the amp is quieter than before, and the mechanical buzzing is completely gone..

and thanks for the input guys, i didnt really want to change the transformer to anything other than what the stock model was,and i dont have very much experience changing trannies either! and it provides more than enough juice to run the amp, and with some tweaking it can run 6l6's (though a little on the cool side). I've done quite a few mods to the amp so far, but nothing in such a way that would mess with the voltage.. mods were primarily based around boosting switches on the input section, altering values in the output section to tighten up bass response, reduce sag, increase dynamics, and increase clarity... as well as replace the bright/dark switch with a sweeping 500k pot, with some different values to change the EQ response a bit... and obviously replaced all chinese 3 mica tubes with solid replacements, that happen to be 1950's GE 6v6's and 12ax7's


but yay! the hulk smash approach actually worked for once!


oh, and no, it was not my first tube amp, and definately not just plain old heater hum. I'm used to noise from my amps, but a mechanical buzzing that could be felt off the chassis, and bell housing, and that was picked up by some other part of the circuit it was new and awful!

Yep good call,, the force was on your side this time.
But do check the current draw of 6L6 verses 6V6
Phil.