PianoMeter – Piano Tuner

PianoMeter is a piano tuning app for professionals and hobbyists that will transform your iPhone or iPad into a professional quality electronic tuning aid. NOTE The "free" version of this app is primarily for evaluation, and it only allows you to tune notes on the piano between C3 and C5. To tune the entire piano you will need to buy an upgrade through an in-app purchase. What makes PianoMeter unique: Unlike most musical instruments, pianos cannot be simply tuned to the generic "equal temperament" frequencies that most tuning apps use. Piano tuning must be "stretched" wide of equal temperament for the piano to sound good. Traditionally this is done by professional piano tuners listening to complicated beat ratios of various musical intervals. PianoMeter makes the process more straightforward by directly measuring the tonal characteristics ("inharmonicity") of each note on the piano and automatically calculating the ideal “stretch” or offset from equal temperament. In other words, it creates a custom tuning for each piano with the best compromise between musical intervals like octaves, fifths, fourths, and twelfths, the way aural piano tuners do when fine-tuning. Functionality and pricing: There are three levels of functionality: a free (evaluation) version, a paid "plus" version with basic tuning functionality, and a "professional" version with features geared towards professional piano tuners. The extra functionality is unlocked through one-time in-app purchases. The Free version includes the following limited functionality: • Tuning functionality for the mid-range of the piano only • Automatic note detection • Ability to measure each note on the piano to see how its current tuning compares to the ideal tuning curve (see if a piano is roughly in tune) • Swipe in the graphing area to show a live frequency spectrum or the inharmonicity of measured notes. Upgrading to "Plus" adds the following functionality: • Tuning functionality for the entire piano • Tune to frequency standards other than A=440 • Tune to historical or custom temperaments • Calibrate device to an external frequency source • A TuneLab-inspired Peak View as an alternative visualization of the pitch using the FFT spectrum. Upgrading to Professional unlocks all features of the "Plus" version, plus the following: • Save and load tuning files, so a piano doesn't need to be re-measured each time it is tuned • Pitch raise mode that calculates overpull for an initial first pass "rough" tuning (for pianos that are extremely flat) • Custom tuning styles: create a custom tuning curve by adjusting interval weighting and stretch • Multi-partial tone generator that plays the target frequencies • New colorful "Tonal Energy" display that shows a brief history of the pitch • Automatically back up tuning files to iCloud • Access to all future features and enhancements Upgrade costs: Free to Plus (approximately US$30) Free to Pro (approximately US$350) Note about permissions This app requires permission to access the microphone on your device and permission to read and write files. In the Pro version, the app can optionally use the "location" permission to tag your tuning files with their geolocation.