The GA-2 from Korg is a tuner designed for use with guitars and basses. It provides needle-style metering with highly visible note-name and string-name readouts, allowing you to accurately see how flat or sharp you are, and to adjust the pegs accordingly. Weighing 2.4 oz, the tuner is quite lightweight and slim, fitting easily into your guitar case or gig bag, and featuring a round-edged body to fit better in your hand.
Dedicated guitar and bass modes interface quickly with specific instruments—and not just their usual varieties; seven-string guitars and basses with up to six strings are accommodated. A microphone is built in, thus offering tuning of acoustic guitars and even other instruments (woodwinds, brass, etc.). You can also tune using Sound Out mode, emitting a tone for you to tune by ear.
A Quinta Flat tuning mode has been programmed into the device to work more seamlessly with the lower, dropped tunings often employed in heavy metal, extending down to five semitones in pitch away from standard tuning. This mode also works with guitars sporting longer-than average scales. The needle conveniently shows you frequency values between A430 and A450 right on the display's meter, so you can tune for a variety of different circumstances on the fly without having to select different calibration modes. The unit utilizes two AAA batteries, and provides between 100 and 200 hours of continuous use, depending on the batteries involved.