Stephen Simpson writes:

> I have a fine Decap dance organ, built in Herentals in 1989, which
> plays from computer tapes encoded with music in streaming form. ...
> The manufacturers suggest that I have the organ converted to MIDI,
> but then all the current repertoire is unusable and who is to say
> that this too will be obsolete in another 10 or 20 years, when
> something 'better' comes along.

I would assume that the pipe valves are actually electrical solenoids.
It is perfectly possible, though possibly expensive, to install
parallel driver circuits so the organ can play both MIDI and streaming
tape. It should take little more than a selector switch and a box of
diodes to accomplish it.  If you follow that route, you may need custom
MIDI files which take the existing voicing of the organ into account,
but transposition of MIDI files is a simple matter.

> Perhaps the best way is to replace the old paper rolls with new paper
> rolls alongside archival storage on computer media, but watch out and
> don't forget to upgrade the storage media when something new comes along!

Of course.  Few advocates of MIDI want to see paper rolls abandoned,
and machines which can play both are available commercially.

I like the way Dave Wasson works with "Trudy", his "concert band organ".
He does all his arranging on a computer,  then he punches and plays
paper rolls.  Damage to a roll is not a big worry because he can punch
another from the master MIDI file.

Why does he continue to use paper to play?  I don't know his actual
reasons, but there is something nice in _seeing_ the notes flow by the
tracker bar, and it proves he is playing "mechanical music," not using
some "electronic keyboard."

Wallace Venable