A4 in Young (1799)

A4 is 440.000 Hz in all tuning systems that use A=440 as their reference. In Young (1799), the surrounding chromatic notes are tuned according to six fifths beginning at C are each narrowed by 1/6 of the Pythagorean comma, with the remaining six fifths pure — a rotation of the Vallotti arrangement by one fifth around the circle.

This system was used for Late Classical keyboard repertoire and Early Romantic piano music.

Chromatic Scale at A4=440 Hz in Young (1799)

The table below shows all 12 chromatic notes at octave 4. A4 is the tuning reference — its frequency is 440.000 Hz in all temperaments at this concert pitch. The other notes show how Young (1799) tunes each interval relative to A4.

Positive cents = sharper than equal temperament. Negative = flatter. 100 cents = 1 semitone.

Young (1799): Mathematical Formula

Thomas Young's 1799 temperament uses the same principle as Vallotti — six comma-narrowed fifths and six pure fifths — but rotates the pattern one step around the circle. While Vallotti narrows the fifths F-C-G-D-A-E-B, Young narrows C-G-D-A-E-B-F#. This rotation shifts the best keys slightly: C major retains excellent thirds, while F major and Bb major benefit less than in Vallotti. The pattern is sometimes described as "Vallotti starting from C rather than F." Young's temperament is named after physicist and polymath Thomas Young, who described it in a paper on the theory of sound and light.

Formula type: Cent offsets from equal temperament

How Young (1799) Sounds

Young (1799) sounds similar to Vallotti — smooth, even, and pleasing across most keys. The rotation from Vallotti means that F and Bb major sound slightly less refined, while D and A major are slightly warmer. The differences between Young and Vallotti are subtle in practice and difficult to distinguish by ear without careful comparison. Both systems share the same egalitarian spirit: no key is particularly bad, and the overall tonal impression is of a warm, slightly richer-sounding equal temperament. Young's system is particularly pleasing for late Classical and early Romantic repertoire that ventures freely through several key areas.

Historical Context

Thomas Young (1773-1829) was a British polymath best known for his contributions to physics — the Young double-slit experiment in optics and his contributions to the theory of elasticity. His 1799 paper in the Philosophical Transactions of the Royal Society describing this temperament placed it in a scientific context of wave interference and acoustics. Young proposed it as a well-tempered solution that could serve as a near-equal standard for keyboard instruments. The temperament appears to have been independently developed alongside Vallotti's system and shares its mathematical structure. It is sometimes used in recordings of Haydn and early Beethoven keyboard works.

Other Tuning Systems for A4

See A4 in all temperaments →

For a full deep dive into Young (1799), see the Tunable guide to Young (1799).