Hi Ian,
a few days ago I tried something similar with a couple of my yamaha psr pro styles which I recorded as backing tracks.
Even though they were GM midifiles they didn't sound as good on kn7 as they did on the psr.
Instead of spending the time editing voices, volumes etc on the kn7
I recorded them as psr pro audio files and then used the jukebox software to put them on the sd card.
It was only an experiment, but I was quite happy with the result.
To me, the audio opens up realms of possibilities. especially if you have earlier model keyboards or synths still floating around. ie
I have a few old Roland GS midifiles that just don't sound right on the KN, and I also still have the old Roland Sound Canvas that they were written for.
Instead of spending ages trying to match up roland & Kn sounds, it's far easier to record the midifile as roland audio, transfer it to the sd card and play it that way.
Saves the main living room from looking like a second hand music store.
I did a bit of a posting on it on the 9th of March.
( Hope this link works)
http://www.synthzone.com/ubbs/Forum25/HTML/001435.html best wishes
Rikki