Youtube user Tiergrinder just posted a video of a Jupiter 8 clone (he?) just built. It used all original components where possible, with "100% the same VCO circuits and MOD CON circuits with the original JP-8", though some of the original rare transistors are replaced with modern equivalents.
Tiergrinder goes on to say that he had to stop at four voices, due to the high number of components required just to finish a single voice.
The original ROland custom IR3109 filter chips ahve been recreated with a simillar OTA filter built from discrete components and the Envelope chips are replaced with Electric Druids VCADSR circuits.
We particularly like the fact the Tiergrinder has gone to great lengths to recreate the case, buttons and sliders of the original - truly a labour of love.
Be sure to watch to the end of the video for some classic synth riffs..