why doesn't the GROUNDLIFT button get rid of the hum?

[earworm]

well, i got this one stinky problem in my bedroom, i don't have a ground, or an earth, whats the correct word, so there is a slight basic 50hz hum in my mixer (soundcraft m8) but i can live with that for the moment,
more annoying is when i plug a guitar in my joemeek vc8 preamp, then the humm gets louder, there is a GROUND switch on the preamp but that doesn't seem to have any effect on the humm,
and today i did a PA with my band and clearly there was no ground, i had an electric shoq twice, and i also noticed that on some mics there was a light electric tension,
when we plugged the guitar in a DI box (cheap monarch DI) and then connected it to my joemeek vc8 (guitar preamp) , then there was a real loud buzz/humm, clicking on the groundlift of the DI didn't do anything, same as the groundlift of the joemeek, no effect,
then we plugged the guitar in the guitaramp and took the direct out of the amp and plugged that in the mixer, alot less buzz this time...

how come that a line6 spider amp gives less buzz than my joemeek vc8?

& how come the groundlift switches don't work?

i remember i did a bigger PA in our youthouse where (thank god) there is a ground/earth, and then the groundlift switch DID have the effect i needed, there it got rid of the buzz...

does this mean that groundlifts only work when there is a ground?

thanks,

earworm

 

[tpreager]

does this mean that groundlifts only work when there is a ground?

Well, if there isn't a ground then how would there be any difference between switching the ground switch on and off???

I would recommend to fix the wiring in your house/studio/basement/loft/bedroom/etc....

Timmy J

 

[DonGraham]

Be real carefull when messing with ungrounded gear!!!!! as stated above you can't lift a ground that doesn't exist........A couple suggestions:

1) try to hook all of your gear to a single ac source (this may not be possible depending on your power requirements) this can help to eliminate multiple paths.

2) try transformer isolating your joe meek from the system

3) create your own ground and tie all chassis to it. (this gets a little more involved but can be done with a 3-5' copper rod sunk into the earth and "wired" to the rack)

4) have the the room rewired for a grounded outlet system (this is the best way to go)

good luck

 

[billyshuler]

Just curious, did you happen to have a computer monitor on in your bedroom, or were you next to a television, even a television that's turned off can cause a hum if you're close enough to it. These things will cause hum but certainly not an electric shock. Be careful with ungrounded gear. I hope you find a solution for this frustrating problem.