CS80 Uni/Poly Mod for Yamaha CS50, CS60 or CS80 [Unison Mode Mod for the CS80 /60/50]

Published on Aug 23, 2015 Timothy Conniff

This mod allows you to stack all voices on Yamaha CS50, CS60, or CS80. If you play one note all voices play. If you play two, then half the voice boards play on one note and the other half on the other and so on until you run out of voices. Details and pic of the board follow.

via this auction

"First, a couple of disclaimers... I am NOT the inventor of this concept. BUT I AM the inventor of the architecture of its design. My only claim on this particular modification is that I have now managed to make it available for virtually anyone, even those of you who do not know how to solder! Through printed circuit board design software, I have managed to go from a prototype to beginning production on a number of boards for the CS series. Obviously, the CS 80 has the most voices, and therefore will have the biggest sound from this modification. Nevertheless, one who has a CS 60 or even a 50 can benefit from this mod. What's more, it is not just a unison or monophonic modification. When you switch to the Unison mode, and play more than one key simultaneously it divides the allocation of voices accordingly. So instead of playing all 16 oscillators on one key, it will divide those 16 by the number of keys you press. Play a 4 note chord, and you get four oscillators on each note. Therefore, on a cs50, playing four notes in the Unison mode would be the same as playing in non unison mode, because the 50 only has 4 voices. In any event, this modification is usable in all three of those aforementioned models. I have recorded a YouTube video, and despite the fact that it is only 27 seconds long, you will be blown away! In fact, I deliberately kept it ridiculously simple and straightforward to be incredibly obvious as to its benefit.
. I am making it available in two forms: 1 for those of you who do not know how to solder, and the second is for anyone who has the skills to utilize a soldering iron and heat shrink. Lastly, if you decide to bring me your instrument and have me do the installation, the labor would be $100. Kit cost would still be the same ."