Kevin

Thanks for the suggestion - it seems to work! Of course, the same approach works to get just root chords in a lot of midi-based styles, so it is logical it should work with real tracks too ...

Provided the chords are vanilla "F", "G" or whatever the real bass just plays the root nearly all the time. The original had a bar of "Dm7" and even entering 4 "Dm7"s in the bar gave variations in the pattern. Changing this to "D" worked fine - given the I was exporting the bass to Sonar, the fact that everything else also played "D" not "Dm7" is irrelevant.

You win today's gold star!

Best wishes

Brian