The Korg DTR-2000 Rackmount Digital Tuner displays in cents, hertz, or strobe. It features proprietary circuitry that locks right onto the root tone, ignoring harmonics that confuse cheaper tuners. 7-semitone dropped tunings (a worldwide first), reference pitches from the sound jack, and built-in mic for acoustic tuning provide a wealth of professional options. Tuning modes include chromatic, guitar (6- or 7-string), bass, and 5 types of open tuning. Calibration adjustable from 438-445Hz, select either manual or auto. Lights up rack equipment mounted below.