Time patterns (smooth time)

The fol­low­ing is a sim­ple gram­mar illus­trat­ing the use of time pat­terns in smooth time. Whereas stri­at­ed time is filled with (reg­u­lar or irreg­u­lar) puls­es, smooth time does not involve counting.

_mm(120.0000) _smooth

GRAM#1[1] S --> {10 , t1 t2 , Part1 Part2}
GRAM#1[2] Part1 --> {t1 t3 t4 , C4 D4 E4 F4 - A4}
GRAM#1[3] Part2 --> {t3 t1 , B4 C5 _ E5}

TIMEPATTERNS:
t1 = 1/1  t2 = 3/2   t3 = 4/3  t4  = 1/2

In this gram­mar, "t1", "t2" etc. are the time pat­terns arranged in such a way that they define a struc­ture of (irreg­u­lar) "beats" on which notes "C4", "D4" etc. will be located.

The final arrange­ment is as follows:

{10, t1 t2, {t1 t3 t4, C4 D4 E4 F4 - A4} {t3 t1, B4 C5 _ E5}}

Time flex­i­bil­i­ty in Bol Processor is not the effect of arbi­trary numer­i­cal func­tions.  This flex­i­bil­i­ty stems from a time struc­ture — Xenakis’ (1963) struc­ture tem­porelle — that is deeply inter­wo­ven with the syn­tac­tic descrip­tion of music.

If stri­at­ed time is select­ed, the same struc­ture will be dis­played as shown below:

Some time pat­terns were used in Andréine Bel's chore­o­graph­ic work: Shapes in Rhythm.

Reference

• Bel, Bernard. Migrating Musical Concepts: An Overview of the Bol Processor. Computer Music Journal, Massachusetts Institute of Technology Press, 1998, 22 (2): 56-64.