Lessons · Advanced

Building a form

Period, sentence, rounded binary: rules as architecture

% FORM is structure you can name. One piece in G, built out of
% sections that get named once and then reused. First the PERIOD: a
% question and its answer. The antecedent ends OPEN on 2, the
% consequent closes on 1, and both open with the same six notes: the
% answer is the question re-answered, so the slice says it outright.
 
bpm 75
instrument plain
key g maj
 
Ant ::= 5 _2 '1 _2 7 _4 6 _2 5 _2 6 _4 5 _2 4 _2 3 _4 2 _8
Con ::= Ant[:6] '1 _2 7 _2 6 _2 5 _2 4 _2 2 _2 1 _4
 
assert Ant[:6] == Con[:6]
 
Ant Con
 
 
% Section A is that period with a hand under it. ONE Alberti figure,
% moved by scale step, is the whole accompaniment: I vi IV V under the
% question, I vi V I under the answer; the bass ends open where the
% tune does, then closes with it.
 
Alb ::= {.1 .5 .3 .5} _2
LhA ::= Alb Alb@~5 Alb@~3 Alb@~4
LhB ::= Alb Alb@~5 Alb@~4 Alb
A   ::= {Ant Con, LhA LhB}
 
A
 
 
% Section B is the digression, and it is a SENTENCE: the idea, the
% idea one step up, then the idea FRAGMENTED (the fragment is a slice
% of it), and the line lands on 5 and stays there. The bass holds V
% underneath, leaning on ii once before the return.
 
Idea ::= 5 _2 7 _2 '2 _4
Sent ::= Idea Idea@~1 Idea[:2] Idea[:2]@~1 7 _2 6 _2 5 _4
LhV  ::= Alb@~4 Alb@~4 Alb@~1 Alb@~4
B    ::= {Sent, LhV}
 
B
 
 
% A-prime is a RETURN, not a repeat: the same period an octave up,
% the same harmony at double speed so every chord comes round twice,
% and a turn (3 2 0 1) written into the last cadence.
 
Con2   ::= Ant[:6] '1 _2 7 _2 6 _2 5 _2 4 _2 3 2 0 1 _3
LhFast ::= {LhA}/2 {LhA}/2 {LhB}/2 {LhB}/2
A2     ::= {Ant@~7 Con2@~7, LhFast}
 
A2
 
 
% ROUNDED BINARY, whole: statement, digression, varied return. Three
% names in a row is the entire piece: every note of it was written
% once, above.
 
Piece ::= A B A2
 
Piece

% FORM is structure you can name. One piece in G, built out of
% sections that get named once and then reused. First the PERIOD: a
% question and its answer. The antecedent ends OPEN on 2, the
% consequent closes on 1, and both open with the same six notes: the
% answer is the question re-answered, so the slice says it outright.

bpm 75
instrument plain
key g maj

Ant ::= 5 _2 '1 _2 7 _4 6 _2 5 _2 6 _4 5 _2 4 _2 3 _4 2 _8
Con ::= Ant[:6] '1 _2 7 _2 6 _2 5 _2 4 _2 2 _2 1 _4

assert Ant[:6] == Con[:6]

Ant Con

% Section A is that period with a hand under it. ONE Alberti figure,
% moved by scale step, is the whole accompaniment: I vi IV V under the
% question, I vi V I under the answer; the bass ends open where the
% tune does, then closes with it.

Alb ::= {.1 .5 .3 .5} _2
LhA ::= Alb Alb@~5 Alb@~3 Alb@~4
LhB ::= Alb Alb@~5 Alb@~4 Alb
A   ::= {Ant Con, LhA LhB}

% Section B is the digression, and it is a SENTENCE: the idea, the
% idea one step up, then the idea FRAGMENTED (the fragment is a slice
% of it), and the line lands on 5 and stays there. The bass holds V
% underneath, leaning on ii once before the return.

Idea ::= 5 _2 7 _2 '2 _4
Sent ::= Idea Idea@~1 Idea[:2] Idea[:2]@~1 7 _2 6 _2 5 _4
LhV  ::= Alb@~4 Alb@~4 Alb@~1 Alb@~4
B    ::= {Sent, LhV}

% A-prime is a RETURN, not a repeat: the same period an octave up,
% the same harmony at double speed so every chord comes round twice,
% and a turn (3 2 0 1) written into the last cadence.

Con2   ::= Ant[:6] '1 _2 7 _2 6 _2 5 _2 4 _2 3 2 0 1 _3
LhFast ::= {LhA}/2 {LhA}/2 {LhB}/2 {LhB}/2
A2     ::= {Ant@~7 Con2@~7, LhFast}

% ROUNDED BINARY, whole: statement, digression, varied return. Three
% names in a row is the entire piece: every note of it was written
% once, above.

Piece ::= A B A2

Piece

running…edit it and it re-runs as you type

Building a form · Advanced