NL3 pitch stick, AT and MW all sending random messages?!?

[Rufuss Sewell]

I turned on my precious Lead 3 a couple weeks ago and for some reason it’s sending random CCs all over the place.

I can go without aftertouch so I filter it out in Logic. The biggest culprit is the pitch stick. It randomly modulates from 0 to 64 and everywhere in between, but never right/up in pitch. Only left/down. It sounds like audio rate noise modulation.

If I turn off the pitch stick it sounds fine, but will still send random mod wheel. I have to filter out all CCs in Logic, then it plays fine.

I actually ordered a new pitch stick since that’s all I can’t live without. I installed it, but the same exact thing happens with the new one.

I’m assuming it’s an IC that’s gone bad. Any ideas?

[23skidoo]

Off the top of my head, that's the sort of thing that might happen if a capacitor or an analogue reference voltage goes bad.... you might open it up and check all capacitors, especially the electrolytic ones as those are the most prone to failure from age. Check the power supply rails too, make sure they're stable and steady and have no appreciable noise on them. The potentiometer, pitch stick, and aftertouch are all sensed by the analogue-to-digital converter (I think this is on the 32-bit main mcu, not the DSPs themselves). I would check the analogue reference voltage too, but I haven't looked at the schematic for that part to see which pin it's on.

[23skidoo]

If you google for "Nord Lead 3 Service Manual" you can find it HERE and it indicates that the electronics which performs the A/D conversion of controllers is on the LCD board so I suggest you check its connector(s) with the mainboard, first of all (unplug and clean contacts if needed, then replug, both sides).

There is also a test menu which you can use to check LCD Board and also to calibrate the PB.

[Rufuss Sewell]

Awesome, thank you!