BEHRINGER RACKTUNER BTR2000 Multi-functional tuner including built-in microphone for use with acoustic instruments Useful metronome, adjustable from 30 to 240 bpm with audible and visual beat indicator. You can also work on-the-fly with the manual TAP tempo function Integrated, switchable racklights with high-power LEDs for absolute control over your rack gear 11 different tuner modes (e. g. "chromatic", "banjo" or open tunings) based on 12 equally tempered tones Manual or automatic A-tone standard pitch calibration from 428 Hz to 452 Hz in 1-Hz increments, transposable by a maximum of  7 semitones for especially flexible tuning