Moog Music Forum

Hi, I have a Minimoog that is now only playing the one same pitched note where ever you play on the keyboard, every thing else works fine, it has a Kenton Midi retro fit on it, it developed this symptom after I took it apart to clean it inside, Any ideas would be most welcome!

Thanks, Miles.

Hi Miles - welcome to the forum. The kenton MIDI kit is in the circuit, with the keyboard, that connects both to the rest of the synth. Check all the corrosion prone connectors esp the square black one under the mod wheels. There is a good chance that one of the connectors that you moved or unplugged is corroded and needs gentle cleaning. Best of luck.

Just focus all the small contact springs of each key if there's probably anywhere an endless connection.....

Yes, I'm thinking along the lines of Megavoice: a pitch coil spring resting against the pitch buss bar... ?

This happened a several times to me on different Moog items, exspecially after disassembling and reposing again, despite being very careful......

That's why, after spending a whole day trying to align everything right to avoid hesitant triggering, wailing pitch, missing pitch changes, and all that crap without much success, I had decided to get Kevin Lightner's excellent Opto-Key system. Never regretted it.

But, in retrospect, maybe my keyboard contacts were doomed from the day I bought my Mini ?

OOOOps ! Is looking really scary. I'd have done the same in your place.
My tech had one with an optokey system for repair and he said it's a really fine thing.......
As I didn't use mine that much I think I'll never install one and because I'm a passionate polyphonic player.......

Does anybody know if these "J-Wires" or "J-Springs" are still in production or are to get anywhere as NOS ???

I'm pretty sure that they're not in production anymore. But on this web site:

http://pw2.netcom.com/~arcsound/

(scrolling down on the page)
They advertise that they have both in stock (J-wires and Moog-Type springs) but at a cost of $7.50 each.

CAE sound had a kit with springs. They even have an insertion tool. (44 springs in kit.)
http://www.caesound.net/springcontactskit.aspx
I have purchased from them a few times and they are a very reputable supplier of vintage parts. Have the CAE 4035 filter installed in my Odyssey and they sell those silver inserts for Moog knobs.
The Minimoog used the gold springs. There were a few Moogs that used J wire keyboards. While the J wire keyboards were generally cheaper versions of the nice Pratt & Read Minimoog/modular keybed. The J wire mechanisms did hold up better over the years. And when they went south they were generally easier to clean and repair.
Rebuilding a J wire type right now for a two voice Minimoog. Just finished rebushing and had a set of new keytops.


@thealien666:
Just noticed they now carry the special 50K audio modulation pot for the Minimoog. Worth giving a call there, nice people to deal with. I would call and ask just what the replacement is.
Parts page:
http://www.caesound.net/synthparts.aspx
Mini pots:
http://www.caesound.net/minimoogcontrolpots.aspx

Hey thanks CZ Rider !

I've sent them an email asking about the brand and the measured minimal value of their Minimoog Mod Wheel replacement pot.

I'll keep you posted about their reply.

A second look at those Mini replacement pots.

They look like they may be those PEC type I had found and posted about in another thread. They can be had at Digikey for about $13.00 each. CAE wants another extra $10.00 on top of their standard price. I wonder if they are somehow selected or modified.
PEC 50K audio at Digikey:
http://www.digikey.com/product-detail/e ... -ND/523419
They have all the odd values the Minimoog and modular used including the 50K reverse audio and 1MEG audio. Just discovered these all recently and will order the ones I need from Digikey. Not sure about the Mini mod pot though? I did get the best price for the PEC 10K audio from a reseller on E-bay. Charged only $10 each and free shipping. Must have purchased them in bulk.

Overwhelming
Thank you so much to both
Note ! I've been told yesterday the Jwires (and the cross wires as well) have a Platinum alloy surface and should not be soldered into when being replaced, olnly fastened with knots.......

Note that there are 2 contact springs per key, so if you want to replace them all then you would need 2 CAE spring kits. Springs have to be carefully and rapidly soldered as otherwise the solder will wick up the spring and ruin it.

The other trick is to set each pair into an actuator evenly and at the right height such that the travel is correct and both CV and gate come on and off the buss-bars at exactly the same time (curing "squirelly" keys).

The other thing is that in order to solder these springs from the solder side of the spring card (underside) you have to remove the spring card, so you might want to order a set of rubber mounts too as the old ones fall apart due to age.

Chris

The timing of both Gate and Pitch springs is extremely critical. As a matter of fact, the pitch spring has to contact the pitch buss bar before the gate/trigger one, in an ideal adjustment. Not always easy to accomplish.
That's why I gave up...