units

This module provides some conversion utilities between different units used when dealing with audio

Source:
Example
import { noteToFreq } from 'synth-kit'

noteToFreq('A4') // => 440

Methods

(static) dBToGain(db) → {Number}

Convert decibels into gain.

Parameters:
Name Type Description
db Number
Source:
Returns:

the gain (from 0 to 1)

Type
Number
Example
dBToGain(-3) // => 0.7071067811865475

(static) gainToDb(gain) → {Decibels}

Convert gain to decibels.

Parameters:
Name Type Description
gain Number

(0-1)
Source:
Returns:
Type
Decibels
Example
s.gainToDb(0.3) // => -10.457574905606752

(static) levelToGain(level) → {Number}

Convert from level (an equal power scale from 0 to 100) into gain.

Parameters:
Name Type Description
level Number

from 0 to 100
Source:
Returns:

gain (from 0 to 1)

Type
Number
Example
levelToGain(80) // => 0.9510565162951535

(static) midiToFreq(midi, tuning) → {Number}

Convert from note midi number to frequency

Parameters:
Name Type Description
midi Number

the midi note number (can have decimals)
tuning Number

(Optional) the frequency of a reference A4 note (440 by default)
Source:
Returns:

the note frequency

Type
Number
Example
midiToFreq(69) // => 440
midiToFreq(69.5) // => 452.8929841231365
midiToFreq(70) // => 466.1637615180899

(static) noteToFreq(note, tuning) → {Number}

Convert from note name to frequency

Parameters:
Name Type Description
note String

the note name
tuning Number

(Optional) the tuning of A4 (440 by default)
Source:
Returns:

the note frequency

Type
Number
Example
noteToFreq('C3') // => 130.8127826502993

(static) tempoToFreq(bpm, sub) → {Float}

Convert from beats per minute to hertzs

Parameters:
Name Type Description
bpm Integer

the tempo
sub Integer

(Optional) subdivision (default 1)
Source:
Returns:

the tempo expressed in hertzs

Type
Float
Example
tempoToFreq(120) // => 2
tempoToFreq(120, 4) // => 8