As of this writing, people are just starting to take delivery of the Nord Stage 3 keyboards and I'm beginning to hear some reports from the field. So while this information is preliminary, you may find it helpful.
First item: MIDI CC mappings. As you probably know, in the past Nord has used one set of MIDI CC mappings for the Stage family, another set for the Electro family, and yet another for the C1/C2 family. With the new Stage 3, they have abandoned the old Stage mapping and are now using the same mapping that C1/C2 uses, and the Electro uses for upper manual drawbars. So Stage 3 owners will want to set the DIP switch configuration as if you were using an Electro or C1/C2.
Second item: it seems that the Stage 3 sends out a tremendous amount of data when you move the expression pedal, and this flood of MIDI data overwhelms the DB-1. I do not have access to a Stage 3 and the DB-1 was discontinued years ago, however I would like to support Stage 3 owners if I can.
As of right now, there are three potential solutions available. One of them is to go into the Nord Stage 3's MIDI menu and turn off the Global MIDI channel. If you're not using the Global MIDI channel to control other instruments, this will probably be the easiest and fastest solution for you. Another solution would be to remove the MIDI cable that runs from the Nord's MIDI OUT to the DB-1's MAIN MIDI IN. This will mean you will need to use an auxilliary power source for your DB-1 (the 9 volt battery for a Series II DB-1, or the 9v wall transformer with a Series I unit.)
The third solution is a new version of DB-1 firmware, but that comes with a caveat. In order to make the DB-1 run off MIDI bus power, fairly extraordinary steps were taken to limit its current consumption. One of those steps was to run the DB-1's microprocessor at a lower clock rate. This was a trade-off of performance and power consumption that seemed to work well with the Nord offerings available at the time. The new version of DB-1 firmware has a "turbo mode" where the processor runs at its max clock rate. I need beta testers, but it should run fast enough to keep up with the torrent of MIDI data the Stage 3 produces when you rock the expression pedal with the Global MIDI channel enabled. But you will need to run off your DB-1's auxilliary power source (9v battery or wall transformer). Please message me using the contact link above if you'd like to help test it.
Update 8 Dec 2017: And now I'm hearing reports that the excessive MIDI traffic might be a bug in the Stage 3 firmware. So maybe sit tight on the more drastic fixes until that issue is resolved.
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