In the simplest terms, to transpose the pitch of a musical line is to shift it up or down by a fixed number of semitones or octaves. This is sometimes referred to as “chromatic” transposition. A more sophisticated variation is “scalar” transposition where each note is shifted by a set number of scale steps; this differs from chromatic transposition because some scales may have differing numbers of semitones between steps than other scales.
To chromatically transpose a pitch control voltage, you need a precision adder that can take an external transposition voltage and add it to your main pitch voltage. If the circuit doing the adding is not precise, you may have tracking problems with notes being out of tune. Some transposition modules have switches that allow you to dial in a precise number of semitones or octaves to transpose the pitch voltage by. This comes in handy when two different oscillators require different voltages to produce the same pitch.« Back to Glossary Index