Ensoniq MR Rack parts

Hi as per the guide rather than send the Syntaur guys a question for a part they dont have :slight_smile: thought id ask here.
I have a dead MR Rack trying to fix and stuck on what seems to be the most unique part ever made.:smiley:
…a replacement volume pot!

Ive tried all the obvious places I can think of but no luck after months of serching, it seem as its unique to this synth and even other Ensoniq units dont use it -Im hoping someone may have possibly worked out a subsitute etc - doesnt have to be perfect…just has to work!

thanks for any input
ps. As im not in the US I need somewhere that is contactable by email (& will ship internaitonally)

If the part is unobtainable, substitute one of same value but different design.

Did you not read the “ if anyone has worked out a substitute…” part. Given the technical schematics are not available for this module, nor am I a synth tech who knows every part ever made, or what can be suitably adapted, your comment doesn’t seem very helpful.

I had same problem - received MR Rack with broken volume pot (synth was packed in poor way). After some research there is info about original part:

A5K - 5K Ohm Logarithmic Taper Potentiometer (Audio Dual Potentiometer / Stereo)
RK14 Horizontal type with bushing
Shaft Lenght: 23mm (including thread)
Shaft Diameter: 6mm

You can use also B5K type part (5K Ohm Linear Taper Potentiometer), which have little different movement-resistance bias, but will work same as A5K type.

Check the marking - it must be 5K ohm (502 or 5K printed on body). Do not use 50K ohm (503 or 50K printed).

So I ordered spare parts from Aliexpress:

2 pieces cost 9 USD (including shipping) and worked well after some fitting work. I grinded off about 2mm from both side plates of potentiometer, to get same hight (17.5mm as far I remember - check yours!) after soldering on audio board. I grinded them flat and soldered two 1mm diameter wires on both plates, as pins, holding the potentiometer on audio board. Also the shaft must be extended, because original one is 23mm (including thread), but spare part has 15mm long shaft. So I cutted off 8mm long piece from plastic shaft of broken potentiometer and used superglue to attach it to the new part. Also 7 pins must be cutted off for about 2mm to fit properly (the goal is to get 17.5mm hight from the top of potentiometer to the surface of audio board, after soldering).

Pins of the spare part have exactly the same schematic as original potentiometer, so everything works fine now. Good Luck!

Well! what can i say except : a MASSIVE thank you Sir!!!

Like many of us who buy synths via auction, they occasionally arrived damaged & we’ve had exactly the same experience! This seem perfectly repairable but, I really did try everywhere but no -one could help me tracking down a getting a part so I was left with writing off the whole synth for what seem like a minor damage!.

Where I am these Ensoniqs are neither cheap nor common, so the idea of scrapping an expensive synth has caused me stress for months… so I cant thank you enough for this information- it really helps me out.
Last day of the year for me so what a positive experience to have.

So thanks again Mr Oscillator :slight_smile: and all the best for the coming year.

Cheers!

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