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Malformed time-signature

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(this is my first post so bear with me..)

I was experimenting around with Opusmodus and tried to apply various odd-divisions (particularly prime-numbers interest me)

to some notes and lengths to audition some of them. I've been having some problems with this. 

The error I get most of the time is: "malformed time-signature." Is there a way to avoid this?

1. I wrote: ((h_23w c3)(h c4))  - which results in the aforementioned error when auditioning - notation is usually more or less correct.

2. I wrote ((12/23 c3)(1/2 c4)) - error again

3. I wrote ((h c3 tie)(23w c3)(h c4)) - expressing it like this allows me to audition it, but when I try to write something which repeats the oddity, then it

results in the error again. I tried to repeat the snippet a few times and put the new structure inside parenthesis and then OM

outputs the error again. Something like this: (((h c3 tie)(23w c3)(h c4))((h c3 tie)(23w c3)(h c4))((h c3 tie)(23w c3)(h c4)))

Example: the first (1) example outputs the malformed time-signature in the listener as follows: ((23/2 23/2 2) 46 1)

Something tells me that it somehow interprets my writing wrong.


I'm very new to working like this so I guess it could be just something very obvious that I overlooked.


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The notation in your examples are correct. The 23w length value is a tuplet and is a 23rd part of the whole note.
The best thing I would suggest is to spend some time to read the introduction to OMN.
This way you will progress without to much frustration. Experimentation is the way to learn but the basics are paramount.
Here are the documents I suggest to read:
Introduction to OMN
1st Element - Length
2nd Element - Pitch
3rd Element - Velocity
4th Element - Attribute (Articulation)
Screen Shot 2017-04-26 at 12.40.53.png
The Length, Pitch and Velocity are essentials to understand.
This will give you a good basis to play, explore and experiment with Opusmodus.
Next, check the 'Snippet.opmo' examples.
This document illustrates the omn grammar.
Screen Shot 2017-04-26 at 12.41.10.png
After that I would go through the Howto documentation.
All this will take no more than a few hours.
All the document you’ll find in the Utilities/Documentation panel on the right - second icon.
Screen Shot 2017-04-26 at 13.28.49.png
As for the prime numbers - simple example.
First we generate a few prime numbers:
(setf pnum (primes-to 10))
=> (2 3 5 7)
Now the duration with our prime numbers:
(setf len (gen-length pnum '1/16))
=> (1/8 3/16 5/16 7/16)
And a few more:
(setf my-lengths (gen-eval 12 '(rnd-order len)))
=> ((5/16 1/8 3/16 7/16) (1/8 5/16 3/16 7/16)
    (5/16 3/16 1/8 7/16) (1/8 3/16 5/16 7/16)
    (3/16 5/16 1/8 7/16) (7/16 5/16 3/16 1/8)
    (7/16 3/16 5/16 1/8) (5/16 7/16 3/16 1/8)
    (3/16 1/8 5/16 7/16) (1/8 3/16 5/16 7/16)
    (5/16 7/16 3/16 1/8) (3/16 5/16 7/16 1/8))
Now we generate a 12tone row (at random):
(setf my-pitches (rnd-row :type :pitch))
=> (c4 b4 bb4 fs4 f4 d4 g4 cs4 eb4 a4 e4 gs4)
The MAKE-OMN funtion allows us to put all our parameters together:
(setf my-mat
       :length my-lengths
       :pitch my-pitches))
=> ((qs c4 e. eb4 e e4 q.. a4) (e. f4 q.. fs4 qs b4 e g4)
    (q.. d4 qs cs4 e gs4 e. bb4) (e. c4 q.. eb4 qs e4 e a4)
    (e f4 q.. fs4 qs b4 e. g4) (e d4 q.. cs4 e. gs4 qs bb4)
    (e c4 qs eb4 e. e4 q.. a4) (e f4 qs fs4 q.. b4 e. g4)
    (e. d4 qs cs4 q.. gs4 e bb4) (q.. c4 qs eb4 e e4 e. a4)
    (e f4 e. fs4 qs b4 q.. g4) (q.. d4 qs cs4 e gs4 e. bb4))
Here we use the TONALITY-MAP function to force the minor scale on our material.
(tonality-map '(minor :map step) my-mat)
=> ((qs c4 e. eb4 e f4 q.. bb4) (e. f4 q.. qs bb4 e g4)
    (q.. d4 qs e gs4 e. bb4) (e. c4 q.. eb4 qs f4 e gs4)
    (e f4 q.. qs bb4 e. g4) (e d4 q.. e. gs4 qs bb4)
    (e c4 qs eb4 e. q.. bb4) (e f4 qs q.. bb4 e. g4)
    (e. d4 qs q.. gs4 e bb4) (q.. c4 qs eb4 e e. gs4)
    (e f4 e. qs c5 q.. g4) (q.. d4 qs e gs4 e. bb4))


What about lessons with Stephane Boussuge, here is the link to the request:


Best, JP

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