TUNIC OnlyPure is a professional piano tuning application designed for piano tuners and concert technicians who demand maximum tonal purity, structural clarity, and reliability. The app supports both standard tuning temperaments as well as the original Stopper temperament (B. Stopper, 1988), allowing the tuner to choose the tuning philosophy best suited to the instrument, repertoire, and acoustic environment.
AVAILABLE VERSIONS
Premium Version (Subscription)
• Automatic note detection and chromatic note advance
• Additional temperaments
• Calibration possibility for concert pitch
Basic Version (One-time purchase)
• Full keyboard range
• Manual note switching
Free Two-Weeks Trial Version
• Test the tuning engine with full measurement accuracy
• Full functionality to experience the tuning workflow
• Intended for evaluation purposes
KEY FEATURES (Basic & Premium Version)
• No prior measurement of string inharmonicity required
• Immediate start – select A4 pitch and begin tuning
• Automatic compensation of string inharmonicity, stiffness and damping
• Outstanding unison purity and exceptional chord clarity
• Multiple instruments can be tuned to the same reference pitch
• Designed for concert halls, studios and professional environments
STOPPER TEMPERAMENT – PURE TWELFTHS
TUNIC OnlyPure is optimized for the original Stopper temperament, a tuning system based on pure duodecimes (octave + fifth) instead of traditional fifth-based temperaments. This tuning method has been widely used by professional piano and concert technicians in major concert halls worldwide for over 30 years and is valued for its clarity, stability and musical transparency.
ADDITIONAL TUNING TEMPERAMENTS (subscribers only)
TUNIC OnlyPure also supports conventional standard temperaments, allowing tuners to work within familiar tuning frameworks when required. This makes the app suitable for: - traditional tuning workflows - comparison between tuning philosophies - repertoire- or venue-specific requirements The tuner can seamlessly switch between tuning modes without changing the overall workflow.
HARMONIC EQUIVALENT PITCH
Due to string inharmonicity, piano tones do not exhibit an ideal harmonic overtone structure. As a result, the pitch impression of a piano tone differs from that of an ideal harmonic tone with the same fundamental frequency.
TUNIC OnlyPure accounts for this effect by using a harmonic equivalent pitch: a calculated reference pitch corresponding to an ideal harmonic tone that matches the pitch impression of the inharmonic piano tone. This approach ensures consistent tonal relationships and optimal compatibility between piano tones and harmonic instruments.
Consequently, the effective pitch displayed by OnlyPure may differ slightly from the theoretical fundamental frequency. Compared to fundamental-based tuners, deviations of approximately 2–3 cents sharp (typically around 0.8–0.9 Hz at A4) are normal and expected, depending on the instrument’s string properties.
The reference pitch can be manually calibrated if required (subscribers only).
TARGET AUDIENCE
TUNIC OnlyPure is designed for skilled and experienced piano tuners and concert technicians. Due to its high responsiveness and professional tuning philosophy, the app may be challenging for beginners or occasional users.
TERMS OF USE: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/
This is definitely a good app. But the reason why I gave it a four star rating is that it’s not properly calibrated to a 440. When I checked it with my other Tuning app and checked it with my Tuning for it showed that it was about, a few cycles off. I have to pull it up to A440 one to get a 440. if the developer can calibrate it to where it’s supposed to be I would give it a five star rating. As far as accuracy and tuning the piano itself it is great. Tune spin it pianos very well. Just make this one correction and it would indeed be great.
Developer Response
Thanks for your feedback.The calibration not being exactly 440Hz at A4 is a feature - please refer to our App's description for details. Nevertheless, we figure that some users wish to have a possibility to calibrate to exactly 440Hz. We will soon publish an update that allows for manual calibration.
Tunic Only:Pure
Geokras
The best piano tuner app I have tried. As an amateur, I am surprised they advertise it as only for the professional. It even allows for unison tuning non-aurally, as aural tuning can be a challenge without training. Overall, very easy to use.
In Version 2.0.1 we fixed an issue with the calibration factor missing a decimal place. Additionally, we slightly revised and condensed the user notes for manual calibration.
Version 2.0.1
The developer, Patrick Sebastian Stopper, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Privacy practices may vary, for example, based on the features you use or your age. Learn More
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
