SPNT – Spinet is a stretch-tuning reference for the reference stretches. StroboPro can load it as a target curve for a tuning pass with less than 0.1 cent display resolution.
Open the free SPNT – Spinet tunerThis is an 88-key stretch-tuning reference curve: the cents offset each key sits at relative to equal temperament, rising sharp in the treble and flat in the bass (the Railsback curve). Sample A-octaves:
| Note | Hz | Cents |
|---|---|---|
| A0 | 27.50 | -44.7 |
| A1 | 55.00 | -18.4 |
| A2 | 110.0 | -7.8 |
| A3 | 220.0 | -1.5 |
| A4 | 440.0 | 4.0 |
| A5 | 880.0 | 10.0 |
| A6 | 1760 | 17.3 |
| A7 | 3520 | 32.5 |
A pre-configured stretch curve modeled on historical stretch tables from classic hardware strobe tuner manuals (such as the Peterson 490-ST). Designed specifically for small spinet pianos which exhibit extreme high-treble inharmonicity.
For optimal results, do not apply a raw reference stretch directly. You should first measure the specific inharmonicity profile (B-coefficients) of your piano. Once the physical stiffness curve of the strings is analyzed and saved, import this reference stretch curve on top of the measured piano profile. This ensures all individual harmonic rings synchronize perfectly to your piano's actual inharmonicity while applying the targeted octave stretch offsets.
A needle answers "what is the average pitch right now?" A multi-harmonic strobe adds an extra layer to the tuning visualization by showing several harmonics at once, so you can fine-tune more confidently to fractions of a cent.
Published by Applicaudia, the maker of StroboPro. The less than 0.1 cent figure describes the tuner's display resolution, not a lab-measured accuracy specification. Frequency values are equal-temperament approximations.