Graph Tech Guitar Labs introduces the ultimate in the evolution of guitar tuning

Ratio® Balanced Gear Tuning Technology - the perfect balance of speed and precision on every string

Graph Tech Guitar Labs introduces the ultimate in the evolution of guitar tuning: Ratio® Balanced Gear Tuning Technology - the perfect balance of speed and precision on every string.

Tuning your guitar has never been faster, more precise, or intuitive because Ratio® Machine Heads’ individual gear ratios make every string feel and react the same to all tuning adjustments.

Instrument tuning technology hasn’t changed much in the last 300 years. Turn a peg, hope for the best, and you spend half your life tuning your guitar, and the other half going out of tune.

Here’s why:

The core diameter of each string determines how sensitive it is to tension, so accurate tuning has always been a guessing game with traditional single tuned tuners.

Ratio® tuners are calibrated to the core thickness of each string, from the thick bottom E to the slinkiest top strings, so that every string feels and reacts the same to your tuning adjustments making it easy to change tunings quickly and keep your instrument in tune consistently, all the time.


Ratios® are now factory installed by more and more leading manufacturers for their premium line guitars because of their vastly superior performance.

Ratio machine heads are available for acoustic, electric, locking, staggered post, open back and a variety of button options and finishes.

Ratios® fit most headstock sizes without any modifications using the almost invisible InvisoMatch mounting plates. All Ratio® sets come with patented InvisoMatch Mounting Plates, making installation on your guitar easy, eliminating the need for intrusive modifications, and giving you a perfect installation in minutes.