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Paul December
04-22-2010, 05:34 AM
Recently my amp has started to hum very noticeably. If I touch the end of the cable (the end plugging into the uke) the humming goes away. I haven't changed anything in my set-up: cables, power source, and etc.
Additionally, I haven't plugged anything new into other outlets (florescent lights and such). I tried it with a friends uke, and it had the same hummmmmmmmmmmmmm, only louder.
Any ideas? :confused:

DaveVisi
04-22-2010, 06:53 AM
Are you sure something hasn't changed? The fact that touching the tip stops the hum instead of increasing it makes me think there's something wrong in the ground path. Either a different cable is being used and the wiring is reversed, or you lost ground on your power cord (or the outlet itself, worth a check before you electrocute somebody). Or, something came loose somewhere, possibly at the jack wiring as it enters the amp, or the cable connections have gone bad simply from normal flexing. Have you tried a different cable yet?

leftovermagic84
04-22-2010, 08:23 AM
I have this problem too when I plug my micro cube in, but not when I use it on batteries. I read around the net a bit and the general consensus is that the grounding in the house is screwy (technical term).

I live in a 100 year old rented house and I'm moving in a few months and it's just not worth it to address these issues. My terrible "don't try this at home" solution was to take a piece of wire from the inside of a cat5 cable and attach one end to a metal screw on my amp and the other looped around my toe. It grounds the amp and the hum goes away. It's basically like touching the cable all the time, just with your toe.

JT_Ukes
04-22-2010, 08:27 AM
I have this problem too when I plug my micro cube in, but not when I use it on batteries. I read around the net a bit and the general consensus is that the grounding in the house is screwy (technical term).

I live in a 100 year old rented house and I'm moving in a few months and it's just not worth it to address these issues. My terrible "don't try this at home" solution was to take a piece of wire from the inside of a cat5 cable and attach one end to a metal screw on my amp and the other looped around my toe. It grounds the amp and the hum goes away. It's basically like touching the cable all the time, just with your toe.

OK.. that is the goofiest solution i have ever heard..

try a ground isolator plug... ie.. a 3 prong to 2 prong adapter.

leftovermagic84
04-22-2010, 08:29 AM
OK.. that is the goofiest solution i have ever heard..

try a ground isolator plug... ie.. a 3 prong to 2 prong adapter.

goofy, but it's the only thing i can get to work. The micro cube's plug is already only two prongs.

JT_Ukes
04-22-2010, 08:31 AM
goofy, but it's the only thing i can get to work. The micro cube's plug is already only two prongs.

goofy...

nevermind then! :)

Paul December
04-22-2010, 08:31 AM
I have this problem too when I plug my micro cube in, but not when I use it on batteries. I read around the net a bit and the general consensus is that the grounding in the house is screwy (technical term).

My problem is with the Micro Cube also... and I live in a old house too. I'm going to tries batteries and see if it fixes-it-up. If so, then it may be the house I assume.

GrumpyCoyote
04-22-2010, 08:39 AM
As stated above - grounding. An isolated powerstrip / plug can help, as can minor internal surgery on the amp to remove the two prong cable and properly isolate and ground.

leftovermagic84
04-22-2010, 08:40 AM
goofy...

nevermind then! :)

such is life. I think I just need to complete the look by getting pair of overalls to wear with no shirt underneath, and possibly a straw hat.

Paul December
04-22-2010, 08:55 AM
such is life. I think I just need to complete the look by getting pair of overalls to wear with no shirt underneath, and possibly a straw hat.

Please post a picture :)

SailingUke
04-22-2010, 09:37 AM
OK.. that is the goofiest solution i have ever heard..

Whether it is goofy or not depends on which foot you attach it too.
If a surfer has their right foot foward, they are a "goofy footer", so I assume the same applies here.

Skrik
04-22-2010, 11:03 AM
My terrible "don't try this at home" solution was to take a piece of wire from the inside of a cat5 cable and attach one end to a metal screw on my amp and the other looped around my toe. It grounds the amp and the hum goes away. It's basically like touching the cable all the time, just with your toe.

Could give you a shock, if the amp is the source of the grounding woes. If you tried this with a tube amp, it could quite easily kill you, as the voltages are extremely high.

fahrner
04-22-2010, 11:11 AM
Recently my amp has started to hum very noticeably. If I touch the end of the cable (the end plugging into the uke) the humming goes away. I haven't changed anything in my set-up: cables, power source, and etc.
Additionally, I haven't plugged anything new into other outlets (florescent lights and such). I tried it with a friends uke, and it had the same hummmmmmmmmmmmmm, only louder.
Any ideas? :confused:
What DaveV said. Sounds very much like a bad cable between your uke and amp. Have you tried another?

leftovermagic84
04-22-2010, 11:58 AM
Could give you a shock, if the amp is the source of the grounding woes. If you tried this with a tube amp, it could quite easily kill you, as the voltages are extremely high.

no more than touching the cable would. This is just completing a circuit the same way touching the cable does, but this way, you have both hands free to play.