RioTuner
A precision tuner for guitar, bass, ukulele and bouzouki, for Android. Currently in testing; a Google Play release is planned.
How it measures
Most tuner apps time the waveform of a string. RioTuner measures each overtone separately, from the way its phase advances over time, and fits a stiff-string model, fk = k·f0·√(1 + B·k²), to all of them. Real strings are slightly stiff, so their overtones run sharp. The fit separates that from the pitch, so the reading stays exact when a phone microphone barely picks up the low E. A true strobe shows the string's phase against the target: it stands still only when the string is exactly in tune.
Measured accuracy
| Condition | RioTuner | Classic YIN tuner |
|---|---|---|
| Clean pluck | 0.00 | 0.93 |
| Real-string overtone scatter | 0.12 | 0.97 |
| Weak fundamental (phone microphone) | 0.27 | 1.81 |
| Hard pluck, pitch glide | 0.14 | 1.00 |
| Noisy room | 0.12 | 3.95 |
| Very noisy room | 0.15 | 46.7 |
Synthetic plucked strings with known pitch (B1 to E4, random detuning and string stiffness). Accuracy on a real phone also depends on its microphone; device tests are in progress.
Features
- 16 tunings: guitar (standard, drop D, half and full step down, drop C, DADGAD, open G/D/E, 7-string), bass (4- and 5-string), ukulele, bouzouki (CFAD, DAD), baglamas, plus chromatic mode
- Automatic string detection, or tap a string to lock it
- Reference pitch from 380 to 480 Hz in 0.1 Hz steps
- Note names in C♯, D♭ or Do Re Mi
- No ads, no account, no internet permission
Privacy
Sound is analysed on the phone and immediately discarded. Nothing is recorded, stored or sent. RioTuner privacy policy