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Yamaha MOXF8 keyboard, one note plays too loud!

This Yamaha MOXF8 keyboard has one note that plays too loud when more than the slightest of pushes is given. I moved the keypad underneath to a diffenerent octave and the problem followed the keypad. In other words, the note that was too loud, switched to the same note but in a different octave. I can't see anything visually wrong with the keypad contacts. There are two pc contacts per note. One rubber keypad contact opposite the pc contact extends just a hair more than its adjacent rubber keypad contact. How does this translate into detecting how loud to play a note and how do you think this relates to the note that is too loud?

Thanks for your reply.

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David Farber 
Los Osos, CA
Reply to
David Farber
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Total guess on my part, but it probably detects how fast you press the key (rather than how hard you press). If the two contacts are made simultaniously, it thinks you want a loud note. (Or maybe, one contact is stuck on? Or, an input port on an I/O chip is bad?) Good luck.

Reply to
Pat

Usually 2-stage contacts, and timing the difference. Can you swap a pair of the silicone contact pad strips over , to another part of the keyboard to see if the problem moves with it. Check pull-up/down Rs between adjascent keys? Can you easily swap a multiplex line over with another?

Reply to
N_Cook

Try wiping the carbonised contact pads with an cotton bud soaked in IPA. If that fails try a gentle rub of the black pips with a fine emery board & wipe with IPA again.

Regards Joss

Tetigisti acu (Titus Maccius Plautus 254-184BC)

Reply to
Jocelyn Goodey

Hi Clifford,

I will replace the pad assembly. Thanks for the great explanation.

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David Farber 
Los Osos, CA
Reply to
David Farber

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