The Gibson Explorer is a solid-body electric guitar strongly associated with rock music. To get the best results from your Explorer, the string height above the fretboard, or action, must suit your playing style. It's a matter of preference, but low action typically suits those that like to play fast and higher action suits players who prefer longer notes and string bending.
Detune the strings. The Explorer’s stop-bar Tune-o-matic bridge relies on string tension to hold it in place. If the strings are tuned correctly, there is too much tension on the bridge to perform any adjustments. Use a string winder to expedite the detuning process. You don’t need to completely slacken the strings. Loosen them so that they are slack to the point that they lie flat against the pickups.
Adjust the thumb screws that sit underneath each edge of the stop-bar. They adjust the height of the stop-bar, which in turn alters the string height. Turn clockwise to raise the action and counterclockwise to lower the action.
Examine the level of the bridge from the bottom of the guitar, looking down toward the headstock. If there is a tilt either way, adjust the thumb screw on the lower side.
Retune the strings. Plug an instrument cable into the output jack of the Explorer and connect the other end to an electronic tuner. Pluck the low E-string and tighten the machine head until the tuner display indicates proper tuning. Repeat for the other strings.
Play each fret on each string, starting with low E. If there is a residual buzz on any of the frets, the action is too low. Fret buzz is particularly prevalent on the first three or four frets. If there is a buzz, detune the strings and raise the bridge level slightly. If you find that fretting a note is difficult due to increased string tension, the action is too high.
Check the string intonation. Once you have set the action to a height that suits your playing style and have retuned the strings, play the 12th fret of each string and observe the electronic tuner display. The 12th-fret note should give the same reading as the open string. The action adjustment can influence the intonation.
Adjust the saddle position. Use a small Phillips screwdriver to turn the screw in the back of the saddle for any string that has incorrect intonation. The saddle is the individual metal ridge on which the string sits. Tighten the screw to adjust sharp intonation and loosen it to correct flat intonation.