1.0  PROBLEM

I want to create new music arrangements and edit old music roll files
for player organs  -- from small single-rank crank-organs to huge dance
hall organs -- which have been adapted to operate via MIDI wireline
signals.

I need a method to hear the music as I'm working on it, but commercial
MIDI hardware and software isn't suitable, because

(1) The MIDI wireline signals and MIDI files which play these organs
are an image of the music roll, or else are replicas of events of an
organ console and keyboard, and so are un-playable with standard MIDI
programs and hardware.

(2) None of the commercial synthesizers have the intimate sound of a
little crank-organ: the big Rodgers MIDI-controlled organ is made to
sound best in a church or theater, not on a street corner; the Hammond
organ sound really isn't suitable, nor is the sound of the Mormon
Tabernacle organ!  A flute or piccolo voice on a synth doesn't quite
match the sound of a jolly, bearded piccolo pipe on a real organ.
Also,

(3) Even if I had a real organ in my home studio, my neighbors would
complain about the noise!  (I do my best work late at night.  ;)

2.0  OBJECTIVE

This Project Description Document describes an emulated electronic Fair
Organ which solves the problems listed above.  The MIDI wireline
signals will be the same as the MIDI signals which control existing
"MIDIfied" band- and fair-organs.  Specific objectives, in order of
development, are

(1) an Organ Emulator Unit (a "box"), with computer hardware and
software, which accepts music data as MIDI signals in the same format
as the real organ requires, and which converts the data, in real time,
into synthetic pipe organ sounds and outputs the signal to an external
audio amplifier and loudspeakers (or headphones);

(2) An Organ Console which outputs MIDI data in the same format as the
real organ requires (hence same as the Organ Emulator requires), so
that a skilled organist (or two) can play the emulated or real organ
"live", and control the stops registration conveniently;

(3) An emulated Fair Organ, consisting of a fanciful painted facade
which incorporates the Organ Emulator unit, the Organ Console and
loudspeakers, and has provision to add real organ pipes and/or per-
cussion instruments behind it, and also a spool box so that music rolls
can be played.

3.0  APPROACH

1. The organ console is straightforward.  Start with an old two-manual
electronic organ console.  Throw away all old electronics, retain the
keyboards and pedals and stop switches.  Add modern commutator
electronics to scan the keys and stop switches, and a small computer to
put the data into the same MIDI wireline format that the real organ
expects.  Test it with the real "MIDIfied" organ.  Provide a way to
alter the conversion program so that the console can be plugged into,
for example, a Mortier dance hall organ, or a Wurlitzer band organ, or
a Welte Cottage Orchestrion.

2. Once the console has been selected the design and construction of
a Fair Organ facade can commence.  Install a spoolbox in a prominent
window, so the crowd can "see the music roll by."  Provide other
windows for real drums and bells and ranks of pipes which may be
installed later.  Use imagination!

3. The Organ Emulator will be based upon an array of four Sound Blaster
AWE32 sound cards, with special sound fonts created from recordings of
real organ pipes.  With 32 MB RAM on each 'Blaster card it should be
possible to store suitably long sound samples (e.g., 3 to 5 seconds) so
that the problems of "looping" can be avoided.

The four synth cards will enable 120 different pipes to sound
simultaneously; hopefully, enough for a 98-key Mortier.  Percussion
sounds can optionally use the separate FM/FM synth devices which are
co-located on the AWE32 card.  MIDI input will use a completely
separate input card, such as a simple MPU-401.

The real-time operating system will be Linux, running on PC hardware.
Parameter changes ("Mortier 98-key", "Wurl 165", etc.) will be sent to
the emulator via the MIDI wireline as SysEx messages, or entered with a
simple control panel.

4.0  COST & SCHEDULE

The sound cards and support computer hardware will cost about $2000.
A serviceable organ console and new electronics for it is less than
$1500, I guess.  Program development time is not yet estimated.

5.0  TESTING & RESULTS

Testing the performance of the Organ Emulator is simple.  Using the
same amplifier and loudspeakers, perform a "blind-fold test" in which a
recording of the real organ is alternated with the output of the Organ
Emulator, while playing the same song.

The owner of the real organ will not be fooled -- he knows the sound of
his baby's cry!  The project is a success if an ordinary music-lover
can't tell the real organ from the emulated organ!

Robbie Rhodes