CHROMATIC TUNER New Korg guitar tuner to replace the GA-40. New bigger and easier to read screen. New design for easier and more stable use on the music stand. Guitar and bass modes, with support for 7-string guitars and 5- or 6-string basses. Sound Out mode with reference tones. Memory backup and auto shutdown functions. Autonomy of up to 135 hours with 2 AAA batteries.