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dead microkorg

PostPosted: Mon Feb 13, 2012 5:22 pm
by man-009
buddy of mine said he tried an ac adapter with the wrong voltage on his microkorg. it wont fire up now. is this an easy fix or is he screwed? my guess is whatever he used fried it.

Re: dead microkorg

PostPosted: Mon Feb 13, 2012 6:49 pm
by nogginj
i dont think wrong adapter is a common cause for 'frying' gear permanently (ive never fried anything and i used to just plug in any adapter til i found one that worked).

my guess is he's still using the wrong adapter.

Re: dead microkorg

PostPosted: Mon Feb 13, 2012 7:03 pm
by cgren72
most adapters arent rated exactly what they say they are. they may be a few volts off. it probably wouldnt ruin it to power up with at least a decently close adapter. I wouldnt use it like it that all the time though. i bet the microkorg uses a reverse polarity blocking circuit and its just not letting it power up(which is a good thing.) make sure its the right adapter with the correct polarity and voltage and mA

Re: dead microkorg

PostPosted: Mon Feb 13, 2012 7:07 pm
by man-009
he gave it to me so i will get the right adapter and try it out when it arrives..lol when i asked if he had batteries to test, he was to lazy to buy some so i guess it's on me..lol some people!

Re: dead microkorg

PostPosted: Mon Feb 13, 2012 7:22 pm
by cgren72
hopefully that works, if not i would be glad to take it off your hands lol.

Re: dead microkorg

PostPosted: Mon Feb 13, 2012 7:56 pm
by garranimal
Shouldn't be fried unless you see/smell smoke. Like cgren72 said, the polarity has to be correct in addition to voltage and rated amperage. The polarity blocking could be accomplished with a simple diode inside the synth if that's the case and those usually don't go bad if the wrong polarity was used.

If the transformer you have is the right voltage and amps, but backwards polarity then you could cut/re-solder the wires in reverse to get use out it. Just be sure to cover the joints with heat shrink tubing.

Thrift stores and pawn shops usually have heaps of transformer wall-warts for dirt cheap, like around $3. When checking if a used transformer wall-wart is working it is usually ok to use a multi-meter or voltmeter to confirm the power output.

Also be careful to get an AC-to-DC transformer for the Microkorg. I noticed some equipment can use AC-to-AC step down transformers which would definitely be not good for plugging into equipment expecting DC power.

If the Microkorg still doesn't work with the proper transformer then there's the possibility of a blown fuse. I don't know if there is a fuse inside the synth, and/or the transformer pack.

Re: dead microkorg

PostPosted: Mon Feb 13, 2012 9:24 pm
by man-009
thanks so much guys! i will let you know soon. don't know if there is a fuse in the microkorg either?

Re: dead microkorg

PostPosted: Tue Feb 14, 2012 2:16 am
by Stab Frenzy
Microkorg power supply is the same polarity and voltage as a standard Boss-compatible pedal supply, if you've got any of those lying around try it out.

Re: dead microkorg

PostPosted: Tue Feb 14, 2012 2:18 am
by man-009
thanks. i will when i get it.

Re: dead microkorg

PostPosted: Tue Feb 14, 2012 2:39 am
by Hybrid88
hmm, I've seen several Microkorgs that have had this happen, mostly by Aussies who think they can get one cheap from the US and just use a plug adapter :facepalm:

The Microkorg uses a "wall wart" or plugpack P/S and I'm pretty sure there is no fuse or even diode protection on the synth itself. If you're lucky it only blew the plugpack. Chances are you wouldn't have destroyed the synth itself if the plugpack had a fuse or diode protection (not sure on this though, so keep us updated).

I talked to a tech that had one in this same state and it looked like it needed a new motherboard, which he said costs about $300 (as much as a used Micro itself so a dead loss).

So yeah, try it with batteries and see what happens ;)

Re: dead microkorg

PostPosted: Tue Feb 14, 2012 2:17 pm
by man-009
well, i'm sure it's prob going to be dead. maybe someone will want it for parts?

Re: dead microkorg

PostPosted: Thu Feb 16, 2012 2:39 am
by adhmzaiusz
The EMI filter in the power supply of the microkorg is a cheap piece of sh*t. The microkorg could be dead because the tiny coil in the filter is shorting. One easy way of finding this out is to use a DVM in continuity mode and probing all 4 ports on the filter and if all 4 have continuity its shorted. Make sure the korg isn't plugged in of course.

I fixed a dead microkorg by just taking the filter out and bridging wires in its place. Having no filter didn't seem to have any effect on the performance or sound, so i just went with it. The guy i fixed it for is still using it and hasn't noticed anything either, and its been about a year. Hope this helps.

Re: dead microkorg

PostPosted: Thu Feb 16, 2012 2:18 pm
by man-009
the power adapter this is in? or the synth? thanks adhmzaiusz.

Re: dead microkorg

PostPosted: Fri Feb 17, 2012 3:27 am
by sequentialsoftshock
I'd like it for parts if it is dead. Please PM if this is the case ! =D

Re: dead microkorg

PostPosted: Fri Feb 17, 2012 5:51 am
by adhmzaiusz
man-009 wrote:the power adapter this is in? or the synth? thanks adhmzaiusz.


Inside the synth. The part is called M522-C, it might be labeled I can't remember... anyway its on the circuit board near where the power plugs in. Its a little black square with 4 legs soldered to the board. What you need to do is get a digital volt meter that can test continuity, and probe all 4 of the legs and if they all beep (in every combination) inside the chip the coil has shorted. Make sure the synth isn't plugged in though, for risk of shock!

This part is so fragile and cheap i bet alot of dead microkorgs of the future can be blamed for the m522c.