Need help about Auto Acompaniment or "single key chord" feature, sort of

[Argento]

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By reading you I guess I need to provide more explanations on why the heck do I need to kill 80% of the style part...
OK, here it is: I play bass in a jazz band, we used to have a keyboard player but he's gone and we can't find any replacement.
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Have you looked at One Man Band software?, i think is what you need.

http://www.1manband.nl/omb/index.htm

[ekurburski]

I think your best answer is Band-In-A-Box.  Will do everything you want.  http:www.pgmusic.com