Cakewalk CAL Program for WEB Files
by Walter Tenten (030120 MMDigest)

Hello Robbie, Jody, and all of MMD!  Now that I've succeeded in achieving at least a partial (50%) retirement, I performed a work that I had planned since, in 1994, I built two electro-pneumatic controllers for Jürgen Hocker's Ampico pianos, in a fruitful collaboration with Horst Mohr and Jürgen.

Just before Christmas (2002) the work on a third controller for my personal use was finished and I looked into the Web for (free) MIDI files that I could reproduce on my Haines Bros. Ampico piano.  Of course I am aware of the CD-ROMs offered by Wayne Stahnke, Spencer Chase and Peter Phillips.

One sample I found in the MMD Technical Library: back in 1997 Wayne Stahnke submitted a "precision" scan of Ampico roll 57504A, Prelude in C-Sharp Minor, played by Sergei Rachmaninoff.

As this file had not the webs removed, it sounded terrible on the piano.  Looking for a simple solution, I did a little exercise with CAL, the Cakewalk Application Language, and finally had a suitable MIDI file which I could reproduce on my piano.  The result did not sound as brilliant as the same oeuvre on Wayne's TELARC CD, but nevertheless I was very happy about my personal Christmas gift.

I send the CAL program to Robbie for inclusion in the MMD Technical Archive.  Please note that I did it the simplest way, e.g., I did not account for the different length of the holes in the tracker bar.

Best regards from Germany

Walter Tenten
20 Jan 2003 20:06:04 +0100

Files:  (4 kB) is the CAkewalk CAL Script
57504a_ob.mid (18 kB) is the MIDI file without bridges.  (For comparison: the original MIDI file with bridges had 156 kB.)

The WEB file cited is part of a tutorial package donated by Wayne Stahnke to introduce the WEB data file format, which is used to make a hole-for-hole replica of a music roll.  The tutorial is found under the title "Transcribing music rolls" at

The critical component of the Ampico control system is the magnet valve, which must operate reliably and quickly, at 4" to 40" water column suction.  Walter's clever valve design, utilizing a cheap auto relay, is shown at

21 January 2003