"Jazz up" has very few details to describe, Ian, because it does a lot less than people seem to hope (or fear).

If you "jazz up" your tune, it merely changes certain chord values for only that one tune to modern ones. An A is automatically made into an Amaj7, for example. Minor triads become minor 7ths. Nothing happens to your style. Melody stays as is. It is not a rash maneuver. The process is exactly reversible; if you don't care for your jazzed-up result or if you want to try a jazz arrangement in a folk style, jazz things down.

Jazz Up is just a one-shot deal that re-writes one set of chords and doesn't carry though to anything else, anywhere, ever. There's no way to turn it off, because it's never turned on.
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Larry
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