Nord 6 Electro HP Glitch key issue

[d3llio]

Hi everyone.
I recently noticed that on my Electro 6 it will "glitch out" when I play a full chord. It will repeat one of the notes that I'm playing very quickly, it sounds like someone smashing one key at a fast pace. It only seems to do this on specific note combinations, if I play a full chord with this problem, then move it up or down a half-step it will play normally, but it is not predictable on which notes it will have this issue. Any ideas? Thanks!

[maxpiano]

Sounds like one or more key contacts (if that chord) need to be cleaned, if you search the forum or web there are many of posts and even videos on how to that, if you wish to try DYI (if not, you need a technician).

[pterm]

Hi everyone.
I recently noticed that on my Electro 6 it will "glitch out" when I play a full chord. It will repeat one of the notes that I'm playing very quickly, it sounds like someone smashing one key at a fast pace. It only seems to do this on specific note combinations, if I play a full chord with this problem, then move it up or down a half-step it will play normally, but it is not predictable on which notes it will have this issue. Any ideas? Thanks!

This might indicate a defective diode on a key bed circuit board: The key beds use a "key matrix". The matrix switch closure scanning requires diodes in the matrix circuit to isolate multiple closed switches. If the diode has failed as "short-circuit" a closed switch will carry signals from upstream in scanning path. IIRC, this sometimes manifests as multiple key press.

The Nord's use an 8x8 matrix, so I expect you'll find these problem chords exhibit some 8-key separation. Please reply with a list some of the problem chords and we can see if it matches with this pattern.

[d3llio]

Hello,
Thank you for your reply. This does sound correct. As I was figuring out which keys exhibit this behavior, I noticed that the same key names, Gb, C, D etc. will jump two octaves and the same note will have an issue. Does this sound like the same issue you described? Thanks again for any help, I truly appreciate it!

Here’s a link to a photo, I tagged all the keys with the issue.

https://www.dropbox.com/s/k9hnz9bb5uo4s ... .jpeg?dl=0

Also, after a closer inspection, it’s not necessarily the chords that cause the issue. Playing the individual notes does the same, I think perhaps I just started noticing the issue when I was playing more than one note. Most of the keys exhibit the issue with regularity when I play them individually.

[maxpiano]

If it is regular (same keys across octaves) then you should first try to reseat the keyboard cable(s) connectors, if that won't solve then probably the issue is the one described by pterm.

[pterm]

Hi d3llio,
Thanks for posting the picture. I see an 8 key spacing between problem keys. So this indicates a key matrix hardware problem.
As maxpiano suggests, the easiest thing to check is the alignment and seating of the key bed cables' connectors.
The picture also shows the problem notes appear in pairs. This suggests a possible short circuit from perhaps a liquid spill or conductive debris falling into the key bed or the motherboard. Please look for debris or discoloration (corrosion) on circuit boards and between component pins.
Since you removed the top cover, be careful to always touch the metal body of the instrument to discharge any static electricity before touching anything near the circuit boards.
Good luck! Let us know what you find.

[d3llio]

Something else I noticed after opening the top up was that in the silver boxed area there was an accumulation of some kind of hardened plastic-like substance. I’ve experienced this same thing in a Nord C1 Organ I have. It’s display began to malfunction, and I saw this same substance near the power supply. In both cases, I carefully removed it and my C1 organ worked fine after that. I haven’t yet re-assembled my current keyboard, so I will see if that affected anything as well.

[d3llio]

Good news! An electronics technician was able to resolve the issue. There was some foreign matter, possibly liquid spill on the motherboard. After cleaning it the issue was resolved. Thanks everyone for your help!