D#4 — 311.127 Hz
D#4 (D-sharp 4) is 311.127 Hz in standard equal temperament at A=440 Hz. It is MIDI note number 63.
D#4 Frequency in All Tuning Systems
| Temperament | Frequency (Hz) | Cents from Equal | Common Usage |
|---|---|---|---|
| Equal Temperament | 311.127 Hz | 0.00 | Modern standard; piano, fretted instruments |
| Pythagorean | 309.026 Hz | -11.73 | Medieval/early music; string ensemble open fifths |
| Just Intonation (Major) | 313.951 Hz | +15.64 | A cappella vocal, barbershop, Renaissance |
| Just Intonation (Minor) | 313.951 Hz | +15.64 | Minor-key vocal music, string ensembles |
| Quarter-Comma Meantone | 314.838 Hz | +20.53 | Renaissance keyboard, early Baroque organ |
| Third-Comma Meantone | 316.085 Hz | +27.37 | Renaissance vocal music in minor keys |
| Sixth-Comma Meantone | 313.597 Hz | +13.69 | Baroque orchestral ensemble compromise |
| Werckmeister III | 313.597 Hz | +13.69 | Baroque keyboard; Bach contemporaries |
| Werckmeister IV | 311.479 Hz | +1.96 | Baroque keyboard, strong key contrast |
| Werckmeister V | 311.830 Hz | +3.91 | Specialized Baroque keyboard |
| Kirnberger III | 313.597 Hz | +13.69 | Classical-era keyboard, keys near C major |
| Vallotti | 312.536 Hz | +7.82 | Baroque/Classical orchestral tuning |
| Young (1799) | 312.890 Hz | +9.78 | Classical-era keyboard |
| Bach/Lehman | 311.830 Hz | +3.91 | Bach keyboard works, Well-Tempered Clavier |
| Neidhardt | 311.830 Hz | +3.91 | 18th century keyboard, near-equal alternative |
| Kellner (Bach) | 313.172 Hz | +11.34 | Bach keyboard reconstruction |
Positive cents = sharper than equal temperament. Negative cents = flatter. 100 cents = 1 semitone.
D#4 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) | 311.127 Hz | US, UK, and most modern ensembles worldwide |
| A = 442 Hz | 312.541 Hz | Many European orchestras; France, Germany |
| A = 443 Hz | 313.248 Hz | Berlin Philharmonic; some US orchestras |
| A = 432 Hz | 305.470 Hz | Alternative tuning; Baroque revival |
| A = 415 Hz (Baroque) | 293.449 Hz | Historically-informed Baroque performance |
f = f_at_A440 × (concert_pitch / 440)
Instruments That Play D#4
D#4 (311.127 Hz) falls within the comfortable playing range of 53 instruments.
D#4 and Eb4 — Enharmonic Equivalents
D#4 and Eb4 are enharmonic equivalents — they sound identical at 311.127 Hz but are written differently depending on the musical context.
D#4: D♯ appears in sharp key signatures and is the leading tone in E major. Common key signatures: B major, F♯ major, C♯ major.
Eb4: E♭ appears as the tonic of E♭ major and is prominent in flat key signatures. Common key signatures: E♭ major, A♭ major, B♭ major.
Enharmonic equivalents share the same frequency in equal temperament. In historical temperaments like Pythagorean or meantone, they may differ slightly.
Why D#4 Varies Across Tuning Systems
D#4 shows a maximum deviation of +27.37 cents in Third-Comma Meantone compared to equal temperament. This 27-cent difference is clearly audible to trained musicians and reflects how different tuning philosophies prioritize interval purity over equal distribution.
In Third-Comma Meantone, D#4 is tuned sharper than equal temperament to achieve purer intervals with nearby notes in the tuning system's favored keys.
9 of the 15 non-equal temperaments deviate by more than 10 cents for D#4, making this note one where tuning system choice has a meaningful impact on pitch.
D#4 Across All Tuning Systems
Explore how D#4 is tuned in each historical temperament system. Each tuning system gives D#4 a slightly different frequency, affecting the harmonic character of chords and melodies.
Tune D#4 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.