Music Note Frequency Calculator

Frequency Formula:

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

Frequency:

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1. What is the Music Note Frequency Formula?

The formula calculates the frequency of a musical note based on its MIDI note number. It uses the standard that MIDI note 69 (A4) is tuned to 440 Hz, with each semitone being a factor of 2^(1/12).

2. How Does the Calculator Work?

The calculator uses the frequency formula:

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

Where:

\( Freq \) — Frequency in Hertz (Hz)
\( note \) — MIDI note number (0-127)
69 — MIDI note number for A4 (440 Hz)

Explanation: The formula calculates how many semitones the note is from A4 (440 Hz) and applies the equal temperament ratio of 2^(1/12) per semitone.

3. Importance of Note Frequency Calculation

Details: Accurate frequency calculation is crucial for music production, instrument tuning, sound synthesis, and audio engineering applications.

4. Using the Calculator

Tips: Enter the MIDI note number (0-127). Note 69 is A4 (440 Hz), with higher numbers producing higher frequencies and lower numbers producing lower frequencies.

5. Frequently Asked Questions (FAQ)

Q1: Why is A4 set to 440 Hz?
A: 440 Hz is the international standard for concert pitch, established in 1955 by the International Organization for Standardization.

Q2: What MIDI note number corresponds to middle C?
A: Middle C is MIDI note number 60 (C4), which has a frequency of approximately 261.63 Hz.

Q3: How accurate is this calculation?
A: This provides the theoretically perfect equal temperament frequency. Real instruments may vary slightly due to tuning systems or physical properties.

Q4: Can I calculate frequencies for microtonal notes?
A: The standard MIDI system only supports semitone steps. For microtonal calculations, you would need to modify the formula.

Q5: What's the frequency range of the full MIDI spectrum?
A: MIDI note 0 (C-1) is ~8.18 Hz, and MIDI note 127 (G9) is ~12,543.85 Hz.