FretWave Why you need Fretwave Simply put, your guitar is out of tune. If you do the mathematics for standard guitar fretting you will find that fifths are out of tune by about 1.3% and thirds are out by as much as 2.5%. This is what causes chords to 'go out of tune' as you change positions on the fretboard. The problem is especially noticeable with 'first position' chords played between the nut and the 3rd fret. The patented Fretwave system is a new and remarkably simple fret structure that corrects this in standard guitar fretting.