Korq Z1 SN 006278

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"This synthesizer uses the same multi-oscillator synthesis system (MOSS) tone generator found in the Korg Prophecy which is the reason it is touted as a polyphonic Prophecy. It implements 13 synthesis types, all derived from the original OASYS synthesizer."

Note the original OASYS was never released as a stand alone synth. The Z1, released in 1997, used the technology from it. The OASYS PCI card for the PC (see wikipedia on it here), was released in 1999.

I actually own a Z1 and a Prophecy, and always thought the sound of the Z1 was a bit "dampened" for lack of a better word. It was as if you couldn't quite get the filter to open up all the way - it lacked that extra level of clarity and oomph. I once spoke to someone involved with the development of the Z1, and was told that the DSP chips were underpowered for the engine, and they ran out of time needed to optimize the software to compensate for that. My memory is a little fuzzy though; this was a long time ago. Regarding the Z1 being a poly Prophecy, that is correct only to an extent. They use the same source engine, but the parameters on the two actually differ. One of my favorite patches on the Prophecy is "Prophetic Step". I was curious how it would sound polyphonic, so one day I decided to try an mirror the parameters on the Z1. I discovered that the were not the same, and never managed to program the patch on the Z1. I hate to say it but the Prophecy in general, also slightly sounded better to my ears. The Z1 is still a great synth and offers parameters and physical models not available on other synths, aside from the mono Prophecy of course.

The OASYS synth we all know now followed much later in 2005. Wikipedia has an article on it here. As always use the info on Wikipedia as general information and not fact. They still have the Buchla dates wrong. You can find the corrected dates here.