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Anchor
Anchors, usually referring to a byproduct of streams or sometimes chordjacks, are a high concentration of notes in one column that appear consecutively within the same snap interval, typically 1/2. The name anchor comes from the hand motion the pattern creates, in which a finger is essentially anchored to a specific key due to the consecutive, intervallic presses.
Anchor within jumpstreams, highlighted in blue.
Anchor within chordjacks, highlighted in blue.