I analyzed the PA 80 styles by exporting one chord and multi-chord songs sent to a MIDI sequencer. The PA 80 is supposed to have 16 bar patterns but what it really does it this:

A B C D A B C E
A B C D A B C F

So in a supposed 16 bar pattern, there are only 6 and that's for the best of them.

Another common variation is:

A B A C A B A D
A B A C A B A E

for only 5 patterns.

Most others are

A B C D A B C E repeated

or

A B A C A B A D repeated

And even many

A B A D repeated

And while it may be possible to make different styles for different chords, I haven't found any of the built-in styles that do that.

BiaB not only also lets you write different patterns for different chord types, but it allows more than one pattern for each chord type so you don't get exactly the same thing every time. Plus BiaB has the advantage of knowing the chord changes before you start playing. This allows the style author to have special patterns for special circumstances.

Example, at the end of an 8 bar section, (1) if the last chord of that section is a V7 [G7 in the key of C] (2) there is a part marker after the measure and (3) the first chord of the next section is a I chord [C in the key of C}, BiaB can play a bass pattern that walks from the fifth to the root [G to C in the key of c}]. And that's just one example.

Since the arranger keyboards don't know what the next chord is going to be, they cannot be programmed to do this.

Not that the keyboards don't have their own advantages. Every method has its pros and cons. There are some other things I really like about the arranger keyboards, but in the end I like BiaB better for most songs.

Notes

Bob "Notes" Norton smile Norton Music
https://www.nortonmusic.com

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