I wish I had this tutorial years ago when I fixed a dead key on my Studiologic Sledge! This is the best tutorial I've ever seen on the matter! I would have had much more confidence if I had this video back then when I reinstalled the contacts backwards, reassembled everything, then realized it had no velocity sensitivity! 😂 You fuckin' rule, Sam! Long live Syntaur!

1:30 the most common cause of this "failure" is when the operator has inadvertently turned "local mode" off, which logically disconnects the keybed to the sound engine (but still sends out MIDI when keys are pressed). A far more common failure I find is one where every nth key stops working, i.e. every 6th key on the keybed doesn't function. This is caused by a single conductor in the ribbon cable either breaking, oxidizing, or otherwise coming disconnected.

Great breakdown Sam :) And starting at the right place - ribbon cables are the worst! They scratch easy every time you insert them (really bad tech) and if they're too scratched you'll have a bunch of keys not working -  need to replace them, no way to fix them reliably. While the mechanics can be sussed. I fixed a JD-800 that arrived with a disconnected ground wire, all the keys loose in the box (tape a piece of cardboard to press down on the keys when shipping!), and - since it was weighted, the glue had come off and I had some of the weights loose in the box as well, but that was actually an easy fix! Just clean the keys and glue the weights back. I also installed a mod to make the sensitivity adjustable.
I especially appreciate testing out the keys and watching out for max velocity, to know how many strips to order. Sliders are not as simple, the carbon is inside!

The background music from 2-4 mins is giving me MASSIVE Thief vibes :)

Thank you for making this video. Very helpful.

Have purchased a few components from Syntaur, excellent quality and a great selection.

3:17 on that specific keybed (same as the JD-800) a common failure is that pressure-fit connector (with the two black plastic fasteners) that presses the ribbon cable against the keybed PCB. Roland was hoping that just by pressing them together that they would stay in perfect electrical contact for all time (spoiler: they don't).

After many years of fixing classic synths, I can say that the #1 problem I come across is: previous repairs by people who should not have been attempting to repair it.

Sam!!!! nice to see you

most of the keyboards I have had to repair has been this very same problem with the keybed contacts needing a good clean.

thanks for giving us what we need. membrane switches with one solid plasic part keyboard are not fun to repair.

I've just fixed some dead keys on my 2 year old Arturia Minifreak. After watching a YouTube video on another Arturia synth i thought I'd give it a go.
Unplugging the ribbon cables always has me sweating, but using Google AI camera function identified the connector types and advised how to unclip them. There was some light corrosion on the metal contacts (Thai environment) and dirt on the graphite contacts. Contact cleaner and very light polishing of the metal strips removed it and got everything working again.
I was very relieved.  ❤❤❤

You neglected to mention the pencil trick (i.e., coloring the contact with a pencil), which has saved me many times. I made a video demonstrating it.

MG 838AR Total Ground works really well for renewing the rubber pills in the contact strips, and also does a great job of repairing carbon PCB tracks.

What about early to mid 80’s synths with brass wire connectors such as my Pro Mars Compuphonic. Some pointers there would be much appreciated.

Hello Sam, Thank you for the instructions, that's encouraging. I'm preparing to clean my JD-800 keybed that has the melting glue issue.

hunting down a replacement contact board replacement can be a real pain on vintage synths .. mine got fried from a power bump during a storm

This is great! I love videos like these! Keep them up. Oh and How often do you encounter cat pee?

2:52 oh noooooo...the dreaded Roland red glue!!! One of the key weights has already fallen out....

Orlando caught you playin sloppy! 😄