Canon Construction

Physics: Canon: strict imitation at a time delay and/or pitch interval. Cancrizans (crab canon): melody runs forward in Voice 1 while Voice 2 runs it backward simultaneously. Bach's Musical Offering (1747) includes a crab canon that works in both directions. Invertible counterpoint: voices can swap (soprano ↔ bass) without harmonic violations. Pachelbel's Canon in D: 28-note descending bass sequence repeated ~28 times over 8-measure units. Infinite canons use modulating sequences (sequences that rise a step each repetition) to loop endlessly without repeating pitch content.