16-channel limit with larger scores

[Jeff Barnes]

I apologize if this question has been asked before.

I want to write a full score for big band and somehow overcome the 15 staff 
limit for midi playback. If I could merge the alto and tenor staves from 4 to 
1, and do the same for trumpets and bones, I would have few enough staves for 
midi output to work.

Is there some utility to combine staves for midi playback?

Regards,
Jeff