Ab1 — 51.913 Hz
Ab1 (A-flat 1) is 51.913 Hz in standard equal temperament at A=440 Hz. It is MIDI note number 32.
Ab1 Frequency in All Tuning Systems
| Temperament | Frequency (Hz) | Cents from Equal | Common Usage |
|---|---|---|---|
| Equal Temperament | 51.913 Hz | 0.00 | Modern standard; piano, fretted instruments |
| Pythagorean | 52.207 Hz | +9.78 | Medieval/early music; string ensemble open fifths |
| Just Intonation (Major) | 52.325 Hz | +13.69 | A cappella vocal, barbershop, Renaissance |
| Just Intonation (Minor) | 52.325 Hz | +13.69 | Minor-key vocal music, string ensembles |
| Quarter-Comma Meantone | 51.403 Hz | -17.09 | Renaissance keyboard, early Baroque organ |
| Third-Comma Meantone | 51.234 Hz | -22.79 | Renaissance vocal music in minor keys |
| Sixth-Comma Meantone | 51.566 Hz | -11.61 | Baroque orchestral ensemble compromise |
| Werckmeister III | 52.030 Hz | +3.90 | Baroque keyboard; Bach contemporaries |
| Werckmeister IV | 51.854 Hz | -1.97 | Baroque keyboard, strong key contrast |
| Werckmeister V | 51.854 Hz | -1.97 | Specialized Baroque keyboard |
| Kirnberger III | 52.030 Hz | +3.90 | Classical-era keyboard, keys near C major |
| Vallotti | 52.030 Hz | +3.90 | Baroque/Classical orchestral tuning |
| Young (1799) | 51.972 Hz | +1.97 | Classical-era keyboard |
| Bach/Lehman | 52.030 Hz | +3.90 | Bach keyboard works, Well-Tempered Clavier |
| Neidhardt | 51.972 Hz | +1.97 | 18th century keyboard, near-equal alternative |
| Kellner (Bach) | 52.030 Hz | +3.90 | Bach keyboard reconstruction |
Positive cents = sharper than equal temperament. Negative cents = flatter. 100 cents = 1 semitone.
Ab1 at Different Concert Pitches
The same note varies in frequency depending on the concert pitch standard used by your ensemble.
| Concert Pitch | Frequency (Hz) | Common Usage |
|---|---|---|
| A = 440 Hz (ISO standard) | 51.913 Hz | US, UK, and most modern ensembles worldwide |
| A = 442 Hz | 52.149 Hz | Many European orchestras; France, Germany |
| A = 443 Hz | 52.267 Hz | Berlin Philharmonic; some US orchestras |
| A = 432 Hz | 50.969 Hz | Alternative tuning; Baroque revival |
| A = 415 Hz (Baroque) | 48.963 Hz | Historically-informed Baroque performance |
f = f_at_A440 × (concert_pitch / 440)
Instruments That Play Ab1
Ab1 (51.913 Hz) falls within the comfortable playing range of 11 instruments.
Ab1 and G#1 — Enharmonic Equivalents
Ab1 and G#1 are enharmonic equivalents — they sound identical at 51.913 Hz but are written differently depending on the musical context.
Ab1: A♭ appears as the tonic of A♭ major and is common in flat key signatures. Common key signatures: A♭ major, D♭ major, E♭ major.
G#1: G♯ appears in sharp key signatures and is the leading tone in A major. Common key signatures: A major, E major, B major, F♯ major, C♯ major.
Enharmonic equivalents share the same frequency in equal temperament. In historical temperaments like Pythagorean or meantone, they may differ slightly.
Why Ab1 Varies Across Tuning Systems
Ab1 shows a maximum deviation of -22.79 cents in Third-Comma Meantone compared to equal temperament. This 23-cent difference is clearly audible to trained musicians and reflects how different tuning philosophies prioritize interval purity over equal distribution.
In Third-Comma Meantone, Ab1 is tuned flatter than equal temperament, reflecting this system's approach to distributing the Pythagorean comma across the chromatic scale.
5 of the 15 non-equal temperaments deviate by more than 10 cents for Ab1, making this note one where tuning system choice has a meaningful impact on pitch.
Ab1 Across All Tuning Systems
Explore how Ab1 is tuned in each historical temperament system. Each tuning system gives Ab1 a slightly different frequency, affecting the harmonic character of chords and melodies.
Tune Ab1 with precision — Get Tunable.
Tunable supports 15+ tuning systems including equal temperament, Pythagorean, just intonation, and historical well-temperaments. See exact Hz values in real-time as you play.