Korg CM400BK Clip-On Chromatic Tuner Microphone

The Korg CM-400 is a clip-on contact microphone designed to work alongside a compatible chromatic tuner, capturing instrument vibrations directly through physical contact rather than relying on airborne sound. Its piezoelectric element translates string and body vibrations into an electrical signal, which is sent to the tuner via a 5-foot cable terminated with a standard 3.5mm monaural mini-plug. This contact-based approach is what makes the CM-400 especially valuable in noisy environments — band rehearsals, classrooms, and backstage warm-ups — where a standard microphone-based tuner would struggle to isolate a single instrument from the surrounding sound.

The clip mechanism opens to a maximum width of 30mm and is designed to grip instrument surfaces securely without scratching or damaging finishes. At just 35 grams, the CM-400 is light enough to leave clipped to a guitar headstock or violin scroll throughout a practice session without adding noticeable weight. The cable itself features a soft, flexible sheath engineered to resist kinking and the wear that comes with regular coiling and uncoiling, while the 3.5mm plug connection is reinforced for a stable, reliable fit. Available in black or white, the CM-400 is a simple, purpose-built accessory that does one thing well: getting a clean vibration signal from your instrument to your tuner.