Hi Cees en Goeden Avond!

My answer to your question may not be phrased in the ideal way but let me try. If I am not mistaken, Part 4 was not available for Easy Record with the KN5000. When the KN6000 and subsequent keyboards were introduced, Part 4 could be selected using the Techni-Chord Orchestrator and that gave us four voices we could play simultaneously as opposed to the three on the KN5000. Thus, it was added to the voices we could record using Easy Record. Hope this answers your question.

Tot Ziens Mijn Vriend!

Chuck