I have long thought about how this should work since I lived in Nashville, but I honestly have no desire to sample a steel and program it. But here is the actual solution:
You have two sets of key groups on the keyboard. The "right hand" key group has 10 primary keys. These represent the 10 strings on the pedal steel in ascending order as they are viewed from the player perspective. Don't pay attention to note names yet.
The "left hand" key group represents each fret on the pedal steel.
The right hand plays the "picking patterns" on the 10 strings. Low velocity is palm mute. Hard velocity is sustain.
The left hand represents the bar placement on the fretboard. Overlapping notes represent a legato slide transition for sustained notes.Velocity of overlapping notes represents the duration of the slide.
Yes, the bar on a real pedal steel can be placed diagonally across multiple frets. The solution here is that two keys played simultaneously with the left hand represent each end point of the bar on the fretboard. Some crafty programming and math regarding bar-size versus start and end points will give you the precise sample and intonation of each key played. Of course, a legato transition for the bar will also need to be accounted for. This is by far the most tricky part of the programming. The rest is cake.
Simple on/off controllers represent each foot pedal on the pedal steel. Customers could use any midi foot pedal with four or more pedals to play this in realtime.
Bar vibrato: Aftertouch for realtime or CC1 for more precise editing.
Volume swells? Expression pedal. This is the same as how a real steel player would use a volume pedal.
Now the debatable part. The knee levers. Depending on implementation, you could take one of two paths. You could go with another set of foot controllers per lever, or one additional set of keys in between the main keys to trigger half and whole bends up and down. Velocity would trigger that. I think I prefer the first method to keep the implementation as a perfect representation of the instrument. But again, it would depend on playability. Everything described up unto the knee levers would be a perfect 1-for-1 implementation.
A roli seaboard would offer additional options, but that would also limit your customer base. In the end, you would need to make sure your programming is tight on this. However, Kontakt can easily handle everything described above.
Enjoy!
