Technical questions for the MPC2000xl and the MPC2000
By IamFG Mon Nov 21, 2011 3:35 am
Hi folks,

I have had my MPC 2000XL for about 11 or so years and have used the hell out of it for all that time without any problems at all.

For about the last 6 months, though, I've been getting an electrical shock (not deadly but not mild/static electricity either) every time I touch any of the plugs on the back (record in or output) whilst also touching the black back plate of the MPC - doesn't seem to happen with the face plate.

I figure this is an earth/ground issue but hell if I know enough to fix it. About a year ago I installed a CF card reader and shortly after that I installed the EB16 board.

Anyone got any ideas what this could be/how I could fix it? Or is this a job for my local pro audio tech? I'm pretty handy with a soldering iron if that's all it would take and I'd rather not hand over my MPC for the next 2 months (there's only one pro audio tech in my city and he takes his time) if I could avoid it.

Cheers
FG
By IamFG Mon Nov 21, 2011 5:45 am
The "lots of kit plugged into a power strip" thing sounds about right for me. However, it has a functioning earth terminal on the plug (both MPC and power strip). That said, I rent an old house so maybe the wiring is not 100%. I'll have an experiment with it in different sockets and see what happens (hopefully not death or, worse still, MPC damage).
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By tapedeck Mon Nov 21, 2011 3:10 pm
yea its important to remember that just because your outlet has three plugs doesn't mean its actually grounded electronically - i've lived in houses where the landlord just slapped grounded jacks on ungrounded circuits just so you plug stuff in.

considering the potential danger, that should really be illegal.
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By JUKE 179r Tue Nov 22, 2011 5:58 pm
FG...
Have you taken apart your MPC recently? Check that the copper tabs on the inside top cover are intact and are bent inward to make contact with the frame of the MPC. This keeps the whole unit grounded.
I've heard in the past that people have taken these off but they are there for a reason.
By IamFG Mon Dec 05, 2011 3:45 pm
I had a look at those tabs but they seem to be making pretty clean contact. Checked it in a number of sockets around the house but it keeps showing the same issue. I'll take it over to a mates place this week and see if it does it there. That way, at least, I'll know if it's an issue with my house or an issue with the MPC.

A few of the tact switches are starting to go anyway, so I'll open it up in the next few weeks to replace those and I'll give it a good service while I'm at it.

I wouldn't really mind the electrocution side of things but it also seems to be affecting the outputs. I have to turn it down to -12dB in the mixer setup menu to prevent it from clipping. Once it's at -12 though it doesn't show any signs of low quality audio or distortion... weird.

Thanks for the advice.
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By twisted-roots Tue Dec 06, 2011 5:34 am
My SCSI input on the back shocked me so now i make it a general rule not to connect the cable when the zip drive is switched on (bit obvious but when your plug is on some indiana jones shit to reach you forget the minor things.... such as not turning into Spidermans arch nemesis shocker.
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By twisted-roots Sat Dec 10, 2011 2:36 am
mr_debauch wrote:oh yeah, and dont plug/unplug stuff from the scsi port while the machine is on.


lmao Yeah i know that now. :(
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By distortedtekno Fri Dec 16, 2011 12:32 am
Sounds like faulty wiring in the electric outlets (no ground, as stated above).
Just a word of caution... do NOT touch that MPC with both hands. There's enough current going through the unit to actually kill you, as it will travel through one arm and through your heart (and stop your heart) to get to the other arm which is grounded to the MPC. Please be careful.
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By Peesnuts Sun Dec 18, 2011 4:11 am
mr_debauch wrote:in the meantime, wear shoes while messing with the mpc


lol^ Safety first! :D

Have you tried something as simple as a power conditioner, or at least a power bar with some type of surge protection? That MIGHT help if the case IS your wall-power.