The most common type of sequencer you’re going to see in a modular synth contains a row of knobs (also known as steps or stages) that may each be set to output a different voltage. A sequencer then goes through steps one at a time. This is most often used to create repetitive musical lines where each note has the same duration, which is popular in trance-like forms of music as well as the classic Berlin School style (70s-era Tangerine Dream and Klaus Schulze; current Red Shift and Node).
Of course, there are many exceptions. Some sequencers allow you to set the duration for each note as well. Some step randomly between the stages, and may even play more than one stage simultaneously (a feature of the “Klee” sequencer). Some sequencers – especially those designed to play percussive lines – are dedicated to gates and triggers rather than variable control voltages, or combine both in the same package. Different sequencer designs may use a method other than dedicated knobs and switches to enter the note values and gate pulses – for example, some allow you to play the desired notes into them in real time, or by stepping along one state at a time.
A sequencer may have its own clock (tempo) source built in, or may accept or require an external clock source to move it through its stages. A few use a continuously variable voltage to choose which step to play at a given time.
A sequencer might or might not have a quantizer built into it, which auto-corrects the pitches you’re dialing in to the nearest semitone or note in the chosen sale. And sequencers don’t have to be used to produce pitched note; some use them to create complex repeating patterns of modulation voltages.« Back to Glossary Index