Tempo, length and meter

Four settings decide how long a bar rings and how long the whole seed runs. The AI picks up tempo and feel from the seed, and the seed needs to be long enough to give the generator something to hold onto — these four control both.

• BPM — the tempo, in beats per minute. This is the speed the generator tends to carry into its result.
• Bars per line — how many bars each line lasts. Normally one (a line is a bar); raise it to stretch every line out, or set it below one to compress them. It scales the time a line — and so each chord on it — is given.
• Time signature — the time signature, written like 4/4, 3/4, or 6/8. It sets how many beats are in a bar; the denominator must be a power of two.
• Loops — how many times the whole progression repeats. More loops make a longer seed.

Example. At 80 BPM, 1 bar per line, 4/4, a line holding one chord lasts one bar — three seconds. Four such lines make a twelve-second pass; with 4 loops the seed is about 48 seconds long. Halve the BPM to 40 and every duration doubles; set bars per line to 2 and each line lasts two bars instead of one.