The difference between the notes of an ukulele is to be exactly half a step between each fret. An instrument where this is given has just or pure intonation; it is accurate.

Octave accuracy

Octave accuracy

Octave accuracy is the most important (and in reality the only achievable and detectable) sub category of pitch accuracy: The sound procuded at the 12th fret (i.e., exactly in the middle of the scale length) is to be exactly one octave higher than the sound of the open string.

Intonation

Intonation

Since a ukulele has at least four strings, the notes of each string must match. Therefore, an ukulele intones properly when tones played on open strings sound exactly like the same notes played on other strings with the finger pressed.

Measuring

Measuring

Tuner

Wenn using a tuner, the following data (in Hertz [Hz] at 440 Hz standard frequency) should be obtained:

C6 Tuning
StringopenHz12th fretHz
1a' 440a' ' 880
2e' 329,6e' ' 659,3
3c' 261,6c' ' 523,3
4g' 392g' ' 784
41) g 196g' 392
D6 Tuning
StringHznote12th fretHz
1h' 493,9h' ' 987,8
2fis' 370fis' ' 740
3d' 293,7d' ' 587,3
4a' 440a' ' 880
Harmonics

By ear, octave accuracy can be determined by picking each string at the 12th fret and comparing the resulting note with the 12th fret harmonics of the same string. If the instrument is accurate, both notes sound identically. (The 12th fret marks the middle of the string. When pushing the string down at this location, its lower half vibrates; using 12th fret harmonics, the upper half vibrates.)

Diagnosis and Correction

Diagnosis and Correction


Sponge Bob Ukulele Setup – Part I


Sponge Bob Ukulele Setup – Part I)