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Best Piano Tuner? Free Strobe with Inharmonicity Awareness
What piano needs that guitar doesn't
Piano strings are thick and stiff, so their overtones ring slightly sharp of clean multiples of the fundamental. That's called inharmonicity, and it's why a piano can't be tuned to pure equal temperament - it has to be stretch tuned, with the upper octaves nudged sharp to match the sharp overtones of the lower strings.
A tuner that ignores this fights you on a piano: it calls the fundamental "in tune" while the overtones (what your ear actually hears) clash. StroboPro's piano handling is built around it:
- Inharmonicity-aware target. The Piano Tuning Assistant models the inharmonicity of the string you're measuring, so the displayed target reflects the real partial structure, not a textbook equal-temperament value.
- Multi-harmonic strobe. Several harmonic rings track different partials of the same string at once, so you can see whether the string is placed consistently or whether one partial is pulling.
How to use StroboPro as a piano tuning assistant
- Open the piano preset and tap Tap to Tune (the mic button). Allow microphone access when asked.
- Mute the neighbouring strings of the unison you're tuning, so you hear only one string.
- Strike the key firmly and let it ring.
- Read the strobe. When the harmonic rings for the relevant partials settle, the string is placed.
For setting the overall stretch across the instrument, work octave by octave and let the assistant's inharmonicity model guide the target.
Important note
StroboPro is a tuning aid. A full aural tuning still means setting the temperament, stretching the treble, and tuning unisons by ear with a temperament strip and mutes. The tool gives you a precise reading of where each string sits, which speeds the work up a lot.
Read the full guide
For more background on strobe tuners and how that applies to piano work, read the full article on the StroboPro blog:
Read "What is a strobe tuner?" on the blog →Related guides
Frequently asked questions
Can you tune a piano with a strobe tuner app?
Yes, as a tuning aid. A strobe like StroboPro shows exactly where each string sits, and because it tracks several partials at once it copes with string inharmonicity. A full tuning still needs ear work for unisons and the overall stretch. Open the [piano preset](/preset/piano/digital-keyboard/equal-temperament) to try it.
What is piano inharmonicity, and why does it matter for tuning?
A piano string's overtones ring slightly sharp of clean multiples of the fundamental, because the string is stiff. That's why pianos are stretch-tuned. The Piano Tuning Assistant models this so the target it shows matches the real string.
Does StroboPro replace a professional piano tuner?
No. Today it's a precise reading tool that speeds up the work and helps hobbyists and apprentices; a concert-quality tuning is still best left to a trained technician who sets temperament and unisons by ear. The Piano Tuning Assistant is in Beta - the aim is to eventually cover the full workflow a tech needs, but it's not there yet.
Why do my piano's high notes sound flat even when a needle tuner says they're in tune?
Because of inharmonicity, the overtones your ear reacts to are sharper than the fundamental a needle reads. The fix is stretch tuning - placing high notes slightly sharp of equal temperament - which a strobe with inharmonicity awareness lets you do on purpose.
Published by Applicaudia, the maker of StroboPro. StroboPro is a tuning aid, not a replacement for a trained piano technician. Resolution figures describe the on-screen display, not lab accuracy.
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