Duo-Art Expression coding
By Robert Pintar
Hello,
I am new to this digest and do not own a player piano (unless MIDI counts). However, I do play the piano (more than 20 years), and I am working on a software project for my master's degree in Computer Science and it was suggested I try posting here to see if I could get some answers to some questions I have. My project is converting piano rolls to the MIDI format, and I had some questions about how the Duo-Art expression encoding worked. I have read some literature on the subject and searched through the archives of this digest, but do not fully understand it yet.
Here is what I think I know with several questions:
There is an accompaniment expression unit and a theme unit. The
accompaniment unit controls the overall sound level of the whole
keyboard, the theme unit makes the 'themed' notes play one degree
(what ever that is) louder than the accompaniment. The accompaniment
level is coded using a series of 4 perforations on the left side of
the roll. These perforations allow for 16 levels of expression.
Q. Is this roughly correct?
Q. What does 'one degree' louder mean?
Q. Is there only one set of accompaniment control, or is the
player divided in half with accompaniment control for both
bass and treble?
For theming, I understand there are 2 perforations ('snake-bites'?)
that activate the theming unit.
Q. Do the theming peforations affect only the notes that are
playing at the exact same time the theming perforations are
'playing'? Or is there some time delay between theme
perforations and the affected notes?
Q. Is there only one set of 'snake-bites' on the roll for the
whole keyboard.?
I have ordered a Duo-Art roll that I can look at and analyze. If anyone has any answers to these basic questions, I would appreciate it. And, I look forward to becoming more knowledgeable on player pianos. When my dad was a boy, his family owned a player piano. He is currently collecting various rolls with the intent of buying a player for himself some day.
Thanks for any help.
Robert
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Robert Pintar email: pintar@spk.hp.com
Hewlett-Packard Company phone: (509) 921 - 3605
Spokane Division fax : (509) 921 - 3991 |
(Message sent Mon 21 Oct 1996, 22:15:28 GMT, from time zone GMT-0700.) |
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