The following is sourced from my favorite internet lesson page: Shut Up And Play
Do yourself a big favor and listen to this with a good set of head phones. Sound quality is superb, as are the lessons.
First, tune to your electronic tuner or tune as you normally do, then try the following: (’H’ = Harmonic tone; arrows indicate "tune to"):
Make sure ’D’ string is at correct pitch.
- D12H ⇐ G 7th fret (tune G 7th fret to the D 12th Fret Harmonic)
- D12H ⇐ B 3rd
- G12H ⇐ E 3rd
- A12H ⇐ G 2nd (or A5H ⇒ D7H)
- Low E 5H ⇐ High E Open (or E5H ⇒ A7H)
- You are listening for the harmonic "beat"frequency when the strings are harmonically out of tune.
- Start tuning the string from below the pitch and come up to the pitch. When tuning a guitar with all the harmonics present (like our Harmony rebuilds!)
you can hear the dissonant harmonic beat frequencies resolve into a consonant or smooth tone as you bring the string to correct tune. Tune slowly.