Electric shoque of my monologue

DonDarko · Post by **DonDarko** » Sun Jul 08, 2018 10:48 pm

I just bought a monologue.
Sometimes (like 1/3) when i play and my soft underarm touches 1 of the 6 screws that hold that main plate i get a shock.
I also bought the "official 30 dmg euro AC adaptor from Korg.

Is this normal? How can i proove this to store cause the problem does not always occur. I turned it off when it shocked me wihtout turning knobs and the next day nothing.. I dont want to go to store and look like a fool...
Maybe somthing to do if im bare feet or wearing shoes? Bad wiring in my monologue?

voip · Post by **voip** » Mon Jul 09, 2018 9:17 am

Is it a single shock, or more like a buzzing sensation? What happens when the back of a finger is swept across the Monologue panel? Is the Monologue connected to any other equipment, either via MIDI, USB, audio in or out, or sync in or out? Where are you located? In a dry atmosphere environment, or high humidity?

DonDarko · Post by **DonDarko** » Mon Jul 09, 2018 12:16 pm

voip wrote:Is it a single shock, or more like a buzzing sensation? What happens when the back of a finger is swept across the Monologue panel? Is the Monologue connected to any other equipment, either via MIDI, USB, audio in or out, or sync in or out? Where are you located? In a dry atmosphere environment, or high humidity?

I live in belgium (realy hot summer atm, realy dry atm)
No, i dont have any other equipment (its my first synth).
For audio i use simple computer boxes (creative, very old ones)

The shock feeling i get is a long buzzzz. I i feel wiht my fingers (who are tick and robust) i hardly feel it. But with the soft skins of my underarm it even suprises me sometimes so i lift my arm up! When my monologue is powered off but the electrical plug is still insererted it still gives me shocks!

What u mean wiht monologue panel? I have dark blue version. U mean that blue plate? The monologu eis made of wood so in the back. If i touch the blue plate i dont feel annything but i suspect that becasue of the seize of the plate!

voip · Post by **voip** » Mon Jul 09, 2018 3:30 pm

The panel referred to was the blue metal top panel of the instrument. So, it is only the screws holding the panel that the buzz sensation comes from?

The buzz sensation signifies that the screw voltage is varying at some frequency, presumably the mains, with respect to any other parts of the room. The Monologue is not directly grounded to the supply, so may tend to "float" at some voltage unless grounded via an amplifier, for example. Most external power supplies are double insulated, so should have negligible leakage current from the mains side to the 9V DC side, though capacitative coupling internally in the power supply may induce a mains-derived voltage onto the DC output. Does the ratings plate on the power supply have the double insulated symbol (a box within a box)?

Does the sensation occur if the Monologue is operated from internal batteries, with the mains supply disconnected?

Does the same thing happen with any other equipment in the room or building e.g. laptop, hi-fi, cooker, microwave oven, or similar.

DonDarko · Post by **DonDarko** » Mon Jul 09, 2018 10:16 pm

voip wrote:The panel referred to was the blue metal top panel of the instrument. So, it is only the screws holding the panel that the buzz sensation comes from?

The buzz sensation signifies that the screw voltage is varying at some frequency, presumably the mains, with respect to any other parts of the room. The Monologue is not directly grounded to the supply, so may tend to "float" at some voltage unless grounded via an amplifier, for example. Most external power supplies are double insulated, so should have negligible leakage current from the mains side to the 9V DC side, though capacitative coupling internally in the power supply may induce a mains-derived voltage onto the DC output. Does the ratings plate on the power supply have the double insulated symbol (a box within a box)?

Does the sensation occur if the Monologue is operated from internal batteries, with the mains supply disconnected?

Does the same thing happen with any other equipment in the room or building e.g. laptop, hi-fi, cooker, microwave oven, or similar.

many other electrical equipments are connected and dont have that problem (record player, laptops, phonecharger, mixtable, ofcourse i try to put out power as much as i can when not needed)

I never operated the monologue on battery so i cant tell.

Yes i think the buzzing only comes from the screws, maybe i dont feel it with topplate cause of more surface, the electric current is divided more? (I dont know exactly how electricity works)

For an answer on the powersuply. If its like 1 big cube with smaller inside? Than yes.... its a korg KA 350 ac adaptor. (thx i learned something new)

Nothing else is connected to the mono except 2 small computer boxes with a woofer! (my next investment)

I went back to store with my monologue today. Its not normal i get buzzes.
I also bought volca beats (my 2nd "synt" , i know its drum comptuer) and I touched the screws, used same AC adaptor (cause my monologue is in repair) and no buzz on the screws of the volca beats.

demonp · Post by **demonp** » Tue Jul 10, 2018 5:33 am

Your device chasis is not grounded. You feel buzz on screws because they are not painted. Just put a wire from korg (anywhere metal) to the floor and check if it helps. the other devices you pluged into connector are plastic.

DonDarko · Post by **DonDarko** » Tue Jul 10, 2018 11:31 am

demonp wrote:Your device chasis is not grounded. You feel buzz on screws because they are not painted. Just put a wire from korg (anywhere metal) to the floor and check if it helps. the other devices you pluged into connector are plastic.

U mean, i hang a wire from the blue plate to the ground (i will try, i want to understand)? I think i should not be doing that, it should work normal.

The mixer is also metal JBS Beats MK2 and that never gives out buzz or shock.

demonp · Post by **demonp** » Tue Jul 10, 2018 1:57 pm

Yep, just hang it to the ground. try it onthe screws also. It shouldn't work like that all the time, but if it solves your problem at least you know its static electricity.

You may also try to use your monologue in another building, just to check.

DonDarko · Post by **DonDarko** » Wed Jul 11, 2018 2:41 am

demonp wrote:Yep, just hang it to the ground. try it onthe screws also. It shouldn't work like that all the time, but if it solves your problem at least you know its static electricity.

You may also try to use your monologue in another building, just to check.

I hope it doesnt escalted i have to wire all screws. My monologue will look like spider and is useless than....

Another thing, its smelled very elictrical (i dont know, maybe analogue synths smell electrical, but it was somehting that caught my attention!)

demonp · Post by **demonp** » Wed Jul 11, 2018 3:56 am

No, one should be enough. But the other option is to bring the device to service.

DonDarko · Post by **DonDarko** » Wed Jul 11, 2018 1:52 pm

demonp wrote:No, one should be enough. But the other option is to bring the device to service.

I brought it back to store. No monologue for 2 weeks....