928 Sample and hold is also very rare. Originally assembled in a separate cabinet, it was adapted on the last modular series * 912 Envelope follower (or Schmit Trigger). One of the most popular modules on the Moog systems * 12 stage phaser. The Moog 12 Stage Phaser was very well known, and originally conceived as an external rack to the Modular systems. * Formant Filter. A new module developed by Arturia, which did not exist on the original Moog systems. * Some of the modules are now interchangeable, allowing to configure - to a certain extent - the Modular the desired way.