B0 — 30.868 Hz
B0 (B0) is 30.868 Hz in standard equal temperament at A=440 Hz. It is MIDI note number 23.
B0 Frequency in All Tuning Systems
| Temperament | Frequency (Hz) | Cents from Equal | Common Usage |
|---|---|---|---|
| Equal Temperament | 30.868 Hz | 0.00 | Modern standard; piano, fretted instruments |
| Pythagorean | 30.937 Hz | +3.87 | Medieval/early music; string ensemble open fifths |
| Just Intonation (Major) | 30.659 Hz | -11.76 | A cappella vocal, barbershop, Renaissance |
| Just Intonation (Minor) | 30.659 Hz | -11.76 | Minor-key vocal music, string ensembles |
| Quarter-Comma Meantone | 30.746 Hz | -6.86 | Renaissance keyboard, early Baroque organ |
| Third-Comma Meantone | 30.694 Hz | -9.79 | Renaissance vocal music in minor keys |
| Sixth-Comma Meantone | 30.781 Hz | -4.89 | Baroque orchestral ensemble compromise |
| Werckmeister III | 30.833 Hz | -1.96 | Baroque keyboard; Bach contemporaries |
| Werckmeister IV | 30.763 Hz | -5.90 | Baroque keyboard, strong key contrast |
| Werckmeister V | 30.903 Hz | +1.96 | Specialized Baroque keyboard |
| Kirnberger III | 30.807 Hz | -3.42 | Classical-era keyboard, keys near C major |
| Vallotti | 30.798 Hz | -3.93 | Baroque/Classical orchestral tuning |
| Young (1799) | 30.833 Hz | -1.96 | Classical-era keyboard |
| Bach/Lehman | 30.833 Hz | -1.96 | Bach keyboard works, Well-Tempered Clavier |
| Neidhardt | 30.833 Hz | -1.96 | 18th century keyboard, near-equal alternative |
| Kellner (Bach) | 30.812 Hz | -3.14 | Bach keyboard reconstruction |
Positive cents = sharper than equal temperament. Negative cents = flatter. 100 cents = 1 semitone.
B0 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) | 30.868 Hz | US, UK, and most modern ensembles worldwide |
| A = 442 Hz | 31.008 Hz | Many European orchestras; France, Germany |
| A = 443 Hz | 31.078 Hz | Berlin Philharmonic; some US orchestras |
| A = 432 Hz | 30.306 Hz | Alternative tuning; Baroque revival |
| A = 415 Hz (Baroque) | 29.114 Hz | Historically-informed Baroque performance |
f = f_at_A440 × (concert_pitch / 440)
Instruments That Play B0
B0 (30.868 Hz) falls within the comfortable playing range of 3 instruments.
Why B0 Varies Across Tuning Systems
B0 shows a maximum deviation of -11.76 cents in Just Intonation (Major) compared to equal temperament. This 12-cent difference reflects how different tuning philosophies prioritize interval purity over equal distribution.
In Just Intonation (Major), B0 is tuned flatter than equal temperament, reflecting this system's approach to distributing the Pythagorean comma across the chromatic scale.
2 of the 15 non-equal temperaments deviate by more than 10 cents for B0, making this note one where tuning system choice has a meaningful impact on pitch.
B0 Across All Tuning Systems
Explore how B0 is tuned in each historical temperament system. Each tuning system gives B0 a slightly different frequency, affecting the harmonic character of chords and melodies.
Tune B0 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.