Keeley produced the K30MS-U 30ms Automatic Double Tracker as a stereo effects pedal designed to bring studio-style automatic double tracking to a live performance context. The unit was built to work with guitar, bass, keyboard, and vocals, and sat in Keeley's line as a tool for musicians who required the thickening and widening effects associated with the double tracking technique developed at Abbey Road Studios.

The pedal offered three distinct modes. Dimension Mode allowed the player to create up to two detuned and delayed voices without the regularity of an LFO oscillator, with user control over tuning and delay time per voice. Abbey Mode simulated parallel tape decks running at varying speeds, producing a wide, lush character distinct from a conventional chorus. Slapback Mode delivered a double-tracked echo with two altered voices. In mono operation, the unit included an onboard reverb control — referred to as the Abbey Verb — that simulated a studio chamber sound. In Stereo Double Tracker Pro Mode, the reverb channel was replaced by independent control over each of the two voices; each voice could be tuned up to 30 cents sharp or flat and delayed by up to 30 milliseconds. Internal switches allowed users to configure the wet output as either dry-plus-effect or effect-only, enabling true double tracking in stereo live use.

For setup questions, relay assignments, or internal switch configuration, a qualified guitar technician or audio engineer familiar with effects routing will be best placed to assist.