How to Use the 7th-Fret Tuning Method on a Bass Guitar
There are three ways to tune a bass guitar to itself: the 5th-fret method, the 7th-fret method, or the harmonics method. The 7th-fret method is similar to the 5th-fret method, but it works in reverse (from high to low). But eventually, all forms of relative tuning come down to this: You tune one string of your bass to a reference pitch, and then you tune the other three strings to that tuned string.
Although this is a method for tuning your bass to itself, you should tune your G string (not your bathing suit, but the highest or skinniest string on your bass) to an outside reference pitch.
In all cases, if the notes don’t match exactly, you hear a wavering sound. When you turn the tuning head for each string, the wavers occur at wider intervals as they approach an exact match. When you find the exact match, the wavering stops and the strings are tuned to one another.
This neck diagram for the 7th-fret tuning method shows you the relationships of frets to open strings. The note with the open circle is one octave above the note with the filled-in circle.
Using a finger on your left hand, press the G string down at the 7th fret.
Make sure that you don’t touch the adjacent (lower) D string.
Strike the G and (open) D strings with your right hand and let them ring together.
The pitches are an octave apart, but it’s the same note. Listen to whether the D string is sharp or flat, and turn the tuning head for the D string accordingly until the strings are in tune with each other.
Press the D string down at the 7th fret.
Strike the D and (open) A strings and let them ring together.
Again, the pitches are an octave apart, but it’s the same note. Turn the tuning head for the A string until it's in tune with the fretted D string.
Press the A string down at the 7th fret.
Strike the A and (open) E strings together and let them ring.
You should be getting the hang of it now. Adjust the tuning head for the low E string until it's in tune. After the E string is in tune, your entire bass will be in tune.