PianoTuner: Piano Strobe Tuner

Precise piano tuner with Railsback stretch curve & inharmonicity analysis.

PianoTuner is the professional piano tuning application designed specifically for acoustic upright pianos and concert grands on Android. Built for piano technicians, musicians, and discerning pianists seeking acoustic purity and sub-cent accuracy.

WHY STANDARD CHROMATIC TUNERS FALL SHORT ON PIANOS
Piano strings possess physical stiffness: because of inharmonicity (Fletcher partial equation), their harmonics do not align precisely on integer multiples of the fundamental frequency. Tuning a piano to rigid mathematical equal temperament results in harsh, beating octaves.

PianoTuner analyzes the individual inharmonicity coefficient (B) of your instrument to compute a custom Railsback stretch curve across all 88 keys — delivering harmonious, beat-free octaves from sub-bass A0 to treble C8.

KEY FEATURES

• True High-Precision Strobe Display:
Real-time phase visualization. A stationary pattern signifies frequency alignment down to fractional cents.

• Dual-Mode Precision Needle Gauge:
±50 cent tuning range with an expanded ±2 cent target window and reactive color feedback.

• Dynamic Pitch Detection (AutoNote):
Continuous, multi-harmonic tracking from A0 to C8 that automatically follows your played notes without freezing on initial pitches.

• Railsback Stretch Curve & Interactive Graph:
Visual plot of cent deviations across all 88 notes. Includes a factory upright baseline curve, with instant custom calibration via the step-by-step measurement wizard.

• Adjustable Concert Pitch (A4 Calibration):
Freely tune reference pitch A4 from 415 Hz (Baroque) to 440 Hz (Standard) and 442–443 Hz (Concert Hall pitch).

• Native Low-Latency Audio Routing:
Direct hardware support for internal microphones, USB audio interfaces, and external measurement microphones at 48,000 Hz using Android UNPROCESSED AudioRecord.

• 100% Offline & Private:
All DSP and audio processing happens entirely on your device. Zero audio data is recorded or sent to cloud servers.

TECHNICAL SPECIFICATIONS
• Audio Pipeline: 48 kHz, 16-Bit Mono PCM
• Spectral Resolution: Dual-Resolution FFT with 7-term Blackman-Harris window (16,384 points for deep bass, 4,096 points for mid/treble)
• Acoustic Model: Fletcher inharmonicity equation fn = n · f0 · √(1 + B · n²)
• Octave Purity: 4:2 and 2:1 partial alignment

FREE & PRO EDITIONS
PianoTuner is fully functional for free with unobtrusive ad support. For professional shop and concert use, a single Lifetime Pro upgrade removes all ads permanently.