Dangerous voltage????


Hero Member
As you know, I have an Epi Valve Junior head which I really like.  The input jack has become loose, and I need to stabilize the jack on the inside to tighten it.  From looking online, people warn novices to NOT open the chassis due to shock hazard.  How dangerous would it be to open the chassis (not just the back to access the area with the tubes)  to hold onto the jack to tighten things?  Is there an easy way to drain the power completely from the amp?  The amp is 5 watts - I'm assuming it's still dangerous.

Any advice?


Not seen the schematic for it.  Some, but not all modern amps have whats called a bleed down resistor in the power supply, to prevent electric shock - after some time has gone by.

Do this - run the amp with your guitar playing into it.  Hit a big nasty chord and pull the wall plug and let the sound decay.  That has bled off a good deal of residual charge.  Then leave it unplugged over night.  Then go in there, and DONT FRIKKING TOUCH ANYTHING but the input jack.
Are they really that dangerouse where if you just TOUCH something wrong you die?!? Or does it normally need to be metal, etc? 
To protect yourself, first make yourself a tin foil hat:


Then get a couple of these alligator clips:


Connect the alligator clips to a length of 18 gauge wire long enough to reach from the tip of the tin foil hat to a serious ground, like a radiator or a drain pipe.

This way, if you don't follow CB's instructions not to touch anything but the input jack, any excessive voltage will pass harmlessly through your noggin to ground!