PolySix keybed replacement

[gearfixer]

I need a new keybed for my PolySix what could I put in it as a replacement? I also would like to replace the keybed in my Moog Rogue.

[rhino]

Don't know what would fit exactly, but a good choice might be one from an Ensoniq ESQ-1: Nice self-cleaning contacts, semi-weighted, good feel... You'd need some major re-wiring though.

[THEODICY]

I'd be interested in something like this if I had a busted polysix: http://matrixsynth.blogspot.com/2010/12 ... nster.html Man, that thing is bad a*s.

[Pro5]

I fitted a very nice playing (compared to the original P6 keys at least) alpha Juno 2 keybed/keys to one of my polysix's. Feels way more fun to play compared to those thin plasticky originals, has a bit of weight and bounce to it now (I believe it's virtually identical to the D-50 keybed, or at least feels like how I remember my D-50 feeling which was decent if a touch rubbery) and is just as fast but feels better quality (has some underkey weights so adds a touch of quality feel to the p6's criminally tacky keybed)

To do this you will need to bear in mind:

• You have to reverse ALL the diodes on the J2 board - this will take ages and you may start going insane
• You will have to butcher your original P6 keybed cable and wire them up to the J2 connectors to suit it's matrix
• when the keybed is in it will need a slight lift at the front (a couple of screws on the inside base will lift it and let you adjust)
• insulate/isolate any dangling metal parts from the J2 bracket/keybed - which is all of them, snap them off with pliers so they don't touch the voice/control board. Refit a P6 bracket if possible on the left side to support it and most importantly...
• Make double/triple/quadruple sure that the metal J2 keybed doesn't touch the transformer area on the far right. You could relocat the PSU further up the board or build some isolating material under the keybed etc

It's actually a fairly easy and enjoyable mod to do and means you also don't have to worry so much about the dodgy key contacts on the P6 original. The J2 keys have never let me down. With the J2 keybed there will be a slightly larger gap left/right between wood end and wheels but it's too small to look ugly imo so I centralised it and called it a day. It's perhaps less than 1 cm gap.

The last point there about dangerous voltages can't be stressed enough when fitting custom keybeds to old synths. I have had a pretty bad shock up the arm during testing (due to me being tired and a stupid oversight) of course, it possibly could have killed me had the house power box not tripped.

In other words, unless you are used to doing stuff like that and are aware of the risks I'd probably leave the original keybed alone as the danger isn't worth it if you can't be precise in your testing of metal on PSU contact points.

Also if you ever plan to sell the synth on I would advise against a possibly dangerous custom keybed (unless it uses a like for like framework from a similar synth) as the new owner may not be aware of the changes and could remove your safety measures for example, and kill himself, and... etc

Having said all that, I've enjoyed my P6 100% more since the swap but It's not for everybody (I still have the original keybed to swap back in if needed too)

I tried various keybeds for size including the 'quality' yamaha SY (85), JX8P but the J2 was the closest fit and needed the least rewiring. Some of the keybeds like the yamaha are in different matrix groups (12s instead of 8s, or 8s instead of 6s can't quite remember) so you would have to sever the group contacts and do all kinds of rewiring to make it match the polysix (I did actually do that before abandoning it for other reasons). most keybeds I looked at also start at different ends, meaning the first group on the p6 is like the last group on a lot of other similar grouped keybeds, the last/first group not being a full set of 6/8 whatever and only what is needed to make it upto 61. You just have to be aware of the grouping/matrix and work around it rewiring and setting up new groups if needs be to feed into the original polysix cabling.

And again, pretty much every keybed I looked at had the diodes reversed compared to P6 which means they won't work (or will just be 'on' all the time) if you don't swap em around (de solder/re solder). Time consuming but not hard in itself.

I picked up a dodgy J2 for next to nothing - had a key matrix problem. Used the keys on the polysix and racked the J2 to play via midi. The keybed paid for itself.

[radek tymecki]

simply clean all contacts using alcohol or sth. or exchange contacts. your keyb will work as new!

[Pro5]

simply clean all contacts using alcohol or sth. or exchange contacts. your keyb will work as new!

And still feel like s**t.


Not what he was asking really, people like to mod, anyone can say 'clean the contacts'

[gearfixer]

My Polysix keyboard works as good as it can but it still feels like c**p. Most of the cheap boards your grandma may use play better. I did use some dow corning 7 and it is a lot better but still.

I would like to find a keybed for the polysix and the rogue that is new from someone like fatar. I just don't know if they have something I could use.

[rhino]

Give this member a call:

http://www.keyparts.co.uk/index.php?opt ... e&Itemid=1

[chipaudette]

Stumbled over this old thread...

Give this member a call:
http://www.keyparts.co.uk/index.php?opt ... e&Itemid=1

Hey! Years ago, I bought a sweet Fatar keybed from these guys. Then I put it into my Polysix. It was a lot of work that required replacing more than just the keybed. The journey is written up, starting here:

http://synthhacker.blogspot.com/2013/02 ... nture.html

Once it was in there, those mods then enabled so many additional follow-on upgrades to the Polysix:

• Aftertouch and Portamento: http://synthhacker.blogspot.com/2013/03 ... -demo.html
• Controllable Detuning: http://synthhacker.blogspot.com/2013/04 ... etune.html
• Sustain Pedal: http://synthhacker.blogspot.com/2013/07 ... pedal.html
• Multi-Voice Polyphony: http://synthhacker.blogspot.com/2014/01 ... -mode.html

And now, I'm working on adding velocity sensitivity! http://synthhacker.blogspot.com/2015/10 ... dream.html

Smell the solder!

Chip

[Stab Frenzy]

I remember stumbling across your blog when I was starting to build my DIY four-voice a couple of years ago, very nice work.