Note Calculator

Note Frequency Formula:

\[ Frequency = 440 \times 2^{(note - 69)/12} \]

Frequency:

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1. What is the Note Frequency Formula?

The note frequency formula calculates the pitch of a musical note in Hertz (Hz) from its MIDI note number. This formula is based on the equal temperament tuning system where A4 (MIDI note 69) is tuned to 440 Hz.

2. How Does the Calculator Work?

The calculator uses the note frequency formula:

\[ Frequency = 440 \times 2^{(note - 69)/12} \]

Where:

\( note \) — MIDI note number (0-127)
69 — MIDI note number for A4 (440 Hz)
12 — Number of semitones in an octave

Explanation: The formula calculates how many semitones the input note is from A4 (440 Hz) and applies the exponential relationship of frequencies in equal temperament tuning.

3. Importance of Note Frequency Calculation

Details: Accurate frequency calculation is essential for music production, instrument tuning, audio programming, and sound design. It helps in generating precise pitches for musical applications.

4. Using the Calculator

Tips: Enter a MIDI note number between 0-127. Note 69 is A4 (440 Hz), with each semitone higher being a 5.946% increase in frequency (equal to the 12th root of 2).

5. Frequently Asked Questions (FAQ)

Q1: What is the frequency range of MIDI notes?
A: MIDI note 0 (C-1) is ~8.18 Hz, MIDI note 127 (G9) is ~12543.85 Hz. The human hearing range is typically 20 Hz to 20,000 Hz.

Q2: Why is A4 tuned to 440 Hz?
A: This is the modern concert pitch standard, though historical tunings varied (e.g., Baroque pitch was often lower at A=415 Hz).

Q3: How do I find the MIDI note number for a specific note?
A: Middle C is note 60 (C4), with each octave adding 12. Sharps/flats are the semitones in between.

Q4: What's the difference between equal temperament and just intonation?
A: Equal temperament divides the octave into 12 equal parts, while just intonation uses pure integer frequency ratios which sound more harmonious but aren't equally spaced.

Q5: Can I calculate frequencies for microtonal music?
A: This calculator uses standard 12-tone equal temperament. For microtonal scales, the formula would need adjustment based on the number of divisions per octave.