Tonnesen Roll Cutting Information
By Richard Tonnesen
Steve Harder requested information about our roll cutting. I initially started to reply directly to him, but since others may be interested, I decided to reply to his request via the list.
My wife Janet and I do business as Custom Music Rolls. We offer a manufacturing capability to individuals who want rolls cut for sale under their own label. We generally prefer to cut 20 or more copies of a given roll, but offer pricing for fewer copies. We do not maintain an inventory of rolls to sell at retail. You may contact us directly at (214) 235-4497 or by e-mail for more information.
I designed and built the roll reader and punch and wrote the programs that control them, but since I have a full time day-job I don't take a very direct role in their routine operation. Janet operates the equipment on a nearly full-time basis. She typically has a backlog of several months production.
The machines operate on standard rolls with up to 100 channels spaced nine per inch on 11.25 inch width paper. This specification includes Ampico A and B, Welte Licensee, Recordo, and 88-note rolls. We have also manufactured rolls for certain orchestrions that use the same paper width and hole spacing.
The reader has a 100 hole tracker bar connected to 100 vacuum operated switches. Paper tension is maintained by separate torque motors on the supply and takeup spools. The paper is advanced by capstan rollers which generate a clock signal each time the paper has advanced the selected distance. This triggers the input circuit to sample the state of the switches. The reader program reads the switch state and generates a perforator control file. The file records a start and stop event for each hole but does not preserve chain bridging or any visual information from the roll.
Alternately, a roll perf file can be created from a MIDI file by a conversion program. This approach was used for John Grant's series of Bolcom's Ghost Rags.
A roll perf file can be displayed and edited, and can subsequently be punched or be converted to MIDI files by piano emulation. This roll reader was used for the conversion of the rolls used for creating the compact disk "Gershwin Plays Gershwin - The Piano Rolls". A piano emulation program by Richard Brandle created the initial MIDI files for the CD from the perf files.
The punch operates at 15 steps per second. The paper advance is about 44 steps per inch. The punch is controlled by another computer, which reads the roll file from the disk and generates punch control signals synchronized with the rotation of the main shaft on the punch. At the end of the roll, the computer turns the punch off. The punch is normally attended only during startup, then the room lights are turned off and the punch is abandoned to complete the roll in the dark.
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(Message sent Wed 28 Feb 1996, 04:42:03 GMT, from time zone GMT-0500.) |
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