D2 · 73.42 Hz

D2 is piano key 18 of 88 and MIDI note 38 - the bass register, where bass lines and a male bass voice live. Play the pure tone below, tune to it, or explore the note in every octave.

73.42Hz
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Download 73.42 Hz tone

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D2 on the staff and the piano

On the bass clef, D2 sits under the first ledger line below the staff.

On the piano, D2 is key 18 of 88, octave 2 - a white key. It is 22 semitones below middle C (C4, key 40).

C4D2

Play it on the online piano, or see all 88 note frequencies on one page.

D2 at a glance

Frequency
73.42 Hz
Wavelength (in air)
4.67 m
MIDI note
38
Piano key
18 / 88
Octave
2
Enharmonic
—

All values assume twelve-tone equal temperament at the international standard pitch of A4 = 440 Hz. In that system every semitone has the same size - a frequency ratio of 2^(1/12) - so D2 is exactly 440 × 2^(-31/12) Hz. Under alternative references the note shifts with the reference: at A4 = 432 Hz, D2 becomes 72.08 Hz.

D in every octave

NoteFrequencyMIDIPiano key
D136.71 Hz266
D2 ←73.42 Hz3818
D3146.83 Hz5030
D4293.66 Hz6242
D5587.33 Hz7454
D61174.7 Hz8666
D72349.3 Hz9878

Each octave doubles the frequency - the simplest relationship in music, and the reason notes an octave apart sound like “the same note, higher”.

Who plays D2

D2 is within the usual range of the piano, bass guitar, cello and double bass. It is outside the usual range of all the classical voice types listed here.

Instruments
  • Piano: A0–C8
  • Bass guitar (4-string): E1–G4
  • Cello: C2–A5
  • Double bass: E1–G4
Voices

None of the usual voice ranges

Ranges are approximate: they are the commonly cited sounding (concert) pitches, and real ranges vary by player, instrument, tuning and repertoire. Guitar, bass guitar and double bass are written an octave higher than they sound; B♭ clarinet and trumpet are written a whole tone higher.

Neighboring notes

One semitone down is C♯2 at 69.30 Hz; one semitone up is D♯2 at 77.78 Hz. Need a frequency between notes, or a different waveform? The tone generator plays anything from 20 Hz to 20 kHz; the note ↔ frequency converter does the math both directions, and the chromatic tuner listens to your instrument and shows the offset in cents.

D2 FAQ

What frequency is D2?

D2 is 73.42 Hz in twelve-tone equal temperament with the standard reference of A4 = 440 Hz. Every semitone step multiplies the frequency by the twelfth root of two (about 1.0595), and D2 sits 31 semitones below A4.

What MIDI number and piano key is D2?

D2 is MIDI note 38 and key 18 of 88 on a standard piano. Octave numbering follows scientific pitch notation, where middle C is C4 (MIDI 60).

Where is D2 on the piano and the staff?

D2 is key 18 of 88 on a standard piano, in octave 2, 22 semitones below middle C. On the bass clef staff it sits under the first ledger line below the staff.

How do I tune to D2?

Play the tone above and match your instrument by ear until the beating between the two pitches slows and disappears, or use the chromatic tuner with your microphone for a cents readout. Small mistunings show up as slow beats: one beat per second at this pitch means you are about 23.4 cents off.