I have followed the discussions on the subject of roll to MIDI
translators lately and maybe it could be of interest that I also
constructed such a device in 1993 or 1994.

I was a 5th year student in electronic engineering at the time and as
I was always interested in recording my own piano rolls, I decided to
design and build a piano recorder which would come in handy for myself
and also be a major project for my studies (I wrote a thesis about it at
the time).

This country has always been fairly limited with the supplies of
electronic parts and information, especially at that time.  Internet as
we know it now, was also not available.  This is why I drew up my own
specs and idea for the recorder.  Here is for the electronics boffins:

The machine consists of a specially designed memory array which is
64-kByte big and a full 96 bits wide.  I designed special boards to make
up a switch-rail with lever-microswitches to fit into a piano just above
the keys but on the front side of the key centre.  There are 88 switches
and one extra for the pedal.

The switches are connected to the machine so that there is one dedicated
bit for each note and one for the pedal with some spare (maybe soft
pedal).  The whole circuit is driven by a clock-generator/control board
that basically counts through the addresses in the memory one by one and
stores the current switch states as it goes along.

The clock speed is variable for experimentation and because there is
a compromise between the accuracy of the sampling and the total time
available for recording.  The faster the clock, the more accurate the
system will store what notes were played  but the less total time before
the memory is full and vice versa.

The machine has a start/stop button and when stopped, the information
stored can be downloaded to a PC in the format of 12 bytes for one 96-bit
word.  This all worked very nicely and my final objective was to build a
single punch electronically controlled perforator to punch my rolls.
I also designed the perforator, drawings and all but have never had
enough enthusiasm again to build it.

Anyway, in 1994 I discovered MIDI and thought that this would be a great
application for my machine.  I wrote the necessary software to convert
the 96 bit 12-byte file format to MIDI files.  I purchased a Sound Blaster
card and presto, it worked.  Since then I only use my machine to record
MIDI from the piano or from rolls being played on that piano (Duo-Art
etc).

It works fine but there is of course no expression, it is just like a
player piano with a suction box.  Of course one can edit some expression
into the MIDI files if so desired.  This makes a great difference when
played back on a Pianomation system.

At a later stage, I also changed the machine layout to use some A-to-D
converter for the pedal and storing its output value in the spare bits of
the machine.  This drastically improved the playback on the MIDI side as
I found that a ON/OFF is not good enough for the pedal if the piano is
recorded by someone who plays it live.  People use the Sustain pedal in
very fine increments and decrements, not like player pianos.

 [ I edited SE performances wherein the artist attemped to make the
 [ sustained sound last longer, by making the loud pedal bobble
 [ the dampers up and down while they are well above the strings.
 [ Nothing musical about it, but it's an amusing effect to watch!
 [ -- Robbie

Anyway, my machine is outdated now and I have made a draught design
for a new one which will have a high speed processor chip that will
be able to sample the keyboard directly to the PC in MIDI format and
with full 128 velocity levels per note.  Then again, one can buy this
nowadays -- it is called a "record strip."

My old machine could still come in handy to record rolls for an
orchestrion: for instance, the switches could be wired to the different
instruments in a band, percussion, accordion, piano, etc.  This should
produce some very live rhythm, not mathematically arranged.

 [ Talk about "wired musicians"!!  :-)  -- Robbie

Hope that someone will find this information interesting, I would
appreciate any comments or ideas.

Has anyone got any information about the system I have heard about that
can scan the information of an existing roll by means of a video camera?
I think MMM in Germany might have such a system for their roll duplicator.
It was under construction when I visited Siegfried Wendel in 1991.

Regards,

Bernt W. Damm,  Restorer of Automatic Musical Instruments,
Cape Town, South Africa
e-mail:   bdamm@maxwell.ctech.ac.za
Tel/Fax:  +27 21 24 1576
(Member of AMICA & GSM)

 [ Joerg Wendel -- are you listening?  Could you tell us about the
 [ video transcriber and the "Mighty One-Arm Pneumatic Punching
 [ Machine?"  (Hmmm.  Can you say that with 1 word in German?  ;)
 [ -- Robbie