D F Tweedie
On a song by song basis you need to do two things:
1st, as you know Purity has a 'GM' mode so that it automatically responds to GM patch messates 0-127 (or 1-128). If you want to use 'higher bank' patches then you must disable 'GM mode' and send all your midi messages using 'bank select' controller messages to Purity. This would include CC 0 MSB (data value, CC 32 LSB (data value) and Program Change (patch # value).
You can then send the GM patches, those you still want to use, to Purity using its bank select structure. What are these values? You'll need to search the Purity documentation to find out.
2nd, now that you've determined the complete address of you patches in Purity, you need to tell BIAB how to find them. Unfortunately only Melody and Solo tracks permit using direct bank select messages written into the BIAB track file ... for the other tracks you can only insert the correct program # using the GM numbers by modifying a style so that it plays that GM patch number (make sure to use 'save as.') So, program # 81, GM fiddle, will play the patch # 81 in Purity ... once you get the bank select messages correct. To modify patch numbers in Melody or Solo tracks go to the 'Notation' window and click on the little '#' sign button on the right side of the menu bar. This will open up a little window where you can enter patch numbers and various controller data and save it to the track.
Now we are at the last part. Go to options/channels. You will see that the far right columns show boxes for MSB and LSB for each track. Here is where you have to insert your Purity bank select value data so that Purity responds with the patch you want.
Make sure to save you song as you work on it. Otherwise the channel settings all disappear. They are only 'remembered' in the song, not in the system.
You can go a step further and learn about *.dk drum patch files. You are supposed to be able to use an alternative drum mapping to set the channels. That way, when you fire up BIAB and open your drum map, you are supposed to be able to recall the channels. FWIW, I've been having some hiccups getting this to properly respond on a regular basis.
Another work around, some what easier in some ways, is to bypass step 2 by exporting your file to midi, and then write the patch numbers with a midi program/ editor. You can now open the altered midi file back in BIAB with all the channels now on the Melody track ... which will respond to bank select controller messages.
One fine point. BIAB will rewrite the patch number on each rotation through the choruses at the beginning of the first bar. So if you have a song with 3 choruses and you rewrite the patch change for the file, you'll have to make sure you either do it 3 times or erase the latter 2 program change messages.
This should get you off to a good start. Purity is a really nice 'softsynth' workstation, far superior to the VSC IMO ... but I haven't bothered myself with the Forte, so I can't compare to that one.
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