In VCV Rack a 1 V increase on a V/oct cable raises pitch by exactly one octave

VCV Rack encodes pitch as control voltage on the 1 V/oct standard: a 1 V increase raises pitch by one octave, so 1/12 V raises it by one semitone. This is what lets a MIDI-CV or sequencer’s V/OCT output track an oscillator’s pitch. Crucially, any output can be patched to any input regardless of signal type — the cable does not enforce meaning — so understanding the intended signal type (audio, CV, V/oct, gate, trigger, clock) is what keeps a patch coherent. Patching a V/oct pitch signal into a filter-cutoff CV input, for instance, is legal but produces cutoff sweeps rather than pitch tracking.

Examples

Patching a MIDI-CV V/OCT output into a VCO V/OCT input gives pitch tracking; playing an octave higher on the keyboard raises the CV by 1 V. Patching that same output into a VCA CV input instead modulates amplitude.

Assessment

Given a V/oct output patched into a VCO V/OCT input, state what CV change corresponds to playing one semitone higher, then explain why patching that output into a filter cutoff does not produce pitch tracking.