Note to Frequency

Equal Temperament

Modern Western music divides the octave into 12 equal semitones. Each semitone is a frequency ratio of ²¹²√2 ≈ 1.0595.

This system is called twelve-tone equal temperament (12-TET). It lets instruments in different keys play together in tune.

MIDI Note Numbers

Every note has a MIDI number — an integer from 0 to 127:

The Formula

f(n) = 440 × 2^((n − 69) / 12)

The anchor is A4 = 440 Hz (MIDI 69). Every 12 semitones is one octave (frequency doubles). Every semitone multiplies by 2^(1/12).

Your Task

Implement noteToFreq(n) that converts a MIDI note number to its frequency in Hz.

Run your code to hear A4 (440 Hz) through your speakers.