2.4 KiB
Timing with at
Every step has a duration. By default, sounds emit at the very start of that duration. at changes when within the step sounds fire -- giving you sub-step rhythmic control without adding more steps.
The Basics
at drains the entire stack and stores the values as timing offsets. Each value is a fraction of the step duration: 0 = start, 0.5 = halfway, 1.0 = next step boundary.
0.5 at kick snd . ;; kick at the midpoint
Push multiple values before calling at to get multiple emits from a single .:
0 0.5 at kick snd .
Two kicks: one at start, one at midpoint.
0 0.25 0.5 0.75 at hat snd .
Four hats, evenly spaced.
The deltas persist across multiple . calls until clear or a new at:
0 0.5 at
kick snd . ;; 2 kicks
hat snd . ;; 2 hats (same timing)
clear
snare snd . ;; 1 snare (deltas cleared)
Polyphonic at
Deltas multiply with polyphonic voices. If you have 3 notes and 2 deltas, you get 6 emits — every note at every delta:
0 0.5 at
c4 e4 g4 note 1.5 decay sine snd .
6 emits: 3 notes x 2 deltas. A chord played twice per step.
Arpeggios with at + cycle
Use cycle inside an at block to pick one note per subdivision:
0 0.33 0.66 at
sine snd [ c4 e4 g4 ] cycle note 0.5 decay .
C4 at 0, E4 at 0.33, G4 at 0.66. cycle advances per iteration of the at-loop.
If the list is shorter than the number of deltas, it wraps:
0 0.25 0.5 0.75 at
sine snd [ c4 e4 ] cycle note 0.3 decay .
C4, E4, C4, E4 — wraps to fill 4 time points.
Generating Deltas
You rarely type deltas by hand. Use generators:
Evenly spaced via .,:
0 1 0.25 ., at hat snd . ;; 0 0.25 0.5 0.75 1.0
Euclidean distribution via euclid:
3 8 euclid at hat snd . ;; 3 hats at positions 0, 3, 5
Random timing via gen:
( 0.0 1.0 rand ) 4 gen at hat snd . ;; 4 hats at random positions
Geometric spacing via geom..:
0.0 2.0 4 geom.. at hat snd . ;; exponentially spaced
Gating at
Wrap at expressions in quotations for conditional timing:
( 0 0.25 0.5 0.75 at ) 2 every
hat snd .
16th-note hats every other bar.
( 0 0.5 at ) 0.5 chance
kick snd .
50% chance of double-hit.
When the quotation doesn't execute, no deltas are set -- you get the default single emit at beat start.