D#2 — 77.78 Hz
D#2 (MIDI 39) vibrates 77.78 times per second at standard concert pitch. Play the reference tone below, or tune to it with the online tuner.
D#2 at different reference pitches
| Reference (A4) | D#2 frequency | Used for |
|---|---|---|
| 415 Hz | 73.36 Hz | Baroque pitch |
| 432 Hz | 76.37 Hz | “Verdi” pitch |
| 440 Hz | 77.78 Hz | Standard concert pitch |
| 442 Hz | 78.14 Hz | European orchestras |
| 444 Hz | 78.49 Hz | European orchestras |
Physical properties
- Period: one cycle every 12.86 ms
- Wavelength in air: ≈ 4.41 m (at 20 °C, 343 m/s)
- MIDI note number: 39
- Octave up: D#3 = 155.56 Hz · Octave down: 38.89 Hz