Little Phatty velocity/keyboard issue

Everything Phatty.
Post Reply
User avatar
Wez
Posts: 2
Joined: Sun Aug 28, 2022 7:53 am

Little Phatty velocity/keyboard issue

Post by Wez » Sun Aug 28, 2022 8:19 am

Hi all - first time poster, new (old!) LP owner. My first Moog even though I've been collecting synths for a while now!

I've just picked up a Stage II, in good condition although it desperately needed calibration (original owner had hardly played it over the last 10 years). Also the pitch bend was very unstable but that seems to have come good after a couple of days.

However it has an issue with the keyboard - approx 10 notes in the middle octave are not sending velocity info (either internally or over MIDI). Before I dismantle it I thought I would see if anyone else has had a similar problem. I do 80% of my own servicing so I'm not afraid of getting in there, but having never worked on one of these I thought it would be prudent to get some advice, any gotchas on getting the keybed out etc.

If it were a single note I would suspect a sensor but I'm guessing it's further downstream - any thoughts or advice would be much appreciated.

Many thanks in advance,
Wez

User avatar
Wez
Posts: 2
Joined: Sun Aug 28, 2022 7:53 am

Re: Little Phatty velocity/keyboard issue

Post by Wez » Tue Aug 30, 2022 8:13 am

Thank you mods for the quick approval :D

A quick update... I've since pulled out the keyboard (the LP is definitely one of the easiest synths I've had to dismantle), and whilst I didn't think it was the issue I thought I should at least clean the key contacts (I've had to do this at some point to most synths I've owned, so might as well while it was out).

It didn't fix the problem, although interestingly I was able to get occasional moments of velocity when manually triggering notes on the contact board. But mostly no joy. To clarify, all the notes are working fine - just no velocity on about 10 keys in a row. No obvious solder issues/trace cracks but I'll get a bit more forensic on it tomorrow.

I'll start looking over the schematic but it won't take me long to reach the limits of my tech abilities - hoping someone here can help point me in the right direction!

Post Reply