A Seiko guitar tuner or other electronic guitar tuner fine-tunes a guitar more accurately than tuning a guitar by ear. Electronic tuners sense and "read" the waveform of a vibrating string and alert you to its accuracy with a visible indicator, such a s a needle or series of LED lights, on a display screen. The indicator shows whether the note is in tune, too low (flat or "b") or too high (sharp or "#"). Because the tuner may not recognise the proper waveform vibration if the strings are too far out of tune, it is always advisable to tune by ear first, using the tuner's "sound" feature to play audible "reference" notes. Most all Seiko tuners and other brands feature both sound and electronic tuning modes.
Place the tuner on a table or in your lap (near the guitar as you are holding it), or plug the tuner into the guitar with a guitar cord if you're tuning an electric guitar.
Press the tuner's "Power" button to turn the tuner on, and then press the "Sound" button. The tuner will play a constant note sound, the name of which will be displayed. Press the "Note" button until the displayed note reads "E6," which is the lowest note and thickest (sixth) string on the guitar.
Turn the tuning key for this string up or down while playing the guitar string, until the string sound matches the note coming from the tuner. The tuning key is attached to the string at the top of the guitar, in the area called the "headstock."
Press the "Note" button again until the displayed note reads "A5." This plays the "A" note. The "A" note is the fifth string on the guitar. Turn the tuning key for this string up or down while playing this string until the string sound matches the note coming from the tuner.
Tune the remaining strings on the guitar in the same way, pressing the "Note" button once to display the note and then playing each subsequent note as you tune. The remaining notes are: D4, 3G, 2B and 1E (the "1E" is the thinnest guitar string).
Press the "Sound" button to turn the sound off and then press the "Auto" button. This sets the Seiko guitar tuner in automatic tuning mode, which detects and displays the string notes as you play them.
Play the sixth guitar string. The tuner will display "E6," and the indicator will tell you whether the string is in tune or not. If the indicator is to the left, slightly tune the string up. If the indicator is to the right, slightly tune the string down. The string is in tune when the indicator remains in the centre position.
Play and tune each subsequent string (A5, D4, G3, 2B, 1E) in the same manner.
Some tuners, including the Seiko SAT501, have a "Manual" button that places the tuner into manual tuning mode. Manual mode allows you to tune individual notes (chosen by pressing the "Note" button). However, it is more convenient to keep the tuner in automatic mode. Most tuners have an "auto shut-off" feature after 10 minutes of non-use that helps conserve battery power. Tuners have built-in microphones for tuning acoustic guitars, so it is important to place the tuner as close to the guitar as possible, and tune in an area relatively free of background noise.
Remove the battery if you plan on storing the Seiko guitar tuner for long periods of time or in very hot or cold environments. This will prevent possible battery leakage, which can damage the tuner. Avoid placing the tuner on a wet surface or near liquids. Moisture may short out the tuner's electronics. If the tuner does get wet, immediately turn off the tuner and open it. Remove the batteries and use a hair dryer to dry the battery compartment and surrounding areas. Leave the tuner open in a dry area for several days before installing new batteries and then test the tuner to make sure it works.