Code, Play and
Rock 'n' Roll
A WebAudio Experiment
Armagan Amcalar
GDG DevFest Berlin 2017
November 4th, 2017
Before we start...
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This is a pedalboard in real life
2013 Pedalboard by Royd Andalis licensed under CC BY 2.0
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This is how it looks in software
pure CSS magic.
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Who am I?
Armagan Amcalar
Head of Software Engineering @ unu GmbH
Founder @ Lonca Works
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AUTHORED ON GITHUB
What is WebAudio?
A standard browser API that enables advanced audio applications within the browsers
3D sound processing in games
Sound production applications
Voice training
Art installations
and anything you can imagine about audio
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WebAudio API basics
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source
channel splitter
delay
biquad
filter
gain
gain
channel merger
target
a network of nodes
WebAudio components
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AudioContext
OfflineAudioContext
GainNode
DelayNode
AudioBufferSourceNode
MediaElementAudioSourceNode
PannerNode
ConvolverNode
AnalyserNode
ChannelSplitterNode
ChannelMergerNode
BiquadFilterNode
DynamicsCompressorNode
WaveShaperNode
OscillatorNode
AudioWorkerNode
pedalboard.js
github.com/dashersw/pedalboard.js
(One of?) the first open-source WebAudio framework
for sound effects
GPL Licensed
Well-documented
Abstractions based on the guitar world:
pedals, pots, switches, LEDs
Built on top of Google Closure Library
Compiles with Google Closure Compiler in Advanced Mode
Uses MVVM architecture
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pedalboard.js components
Stage
Board
Box
Footswitch
Led
Pot
FileInput
StreamInput
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Reverb
Overdrive
Conv
Cabinet
Volume
Stage
The bed for everything, where we live, where we breathe
Board
The container for a bunch of guitar pedals
Box
Parent class of all pedals, has one toggle footswitch, a status LED and a potentiometer for volume
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Input
An abstract class that is a source of sound. FileInput and StreamInput extend Input
FileInput
Lets you use any recorded audio as a source file in various formats as supported by the browser (MP3, WAV, OGG etc.)
StreamInput
Lets you use any recording equipment (mics, guitars, mixers) as a source so you can replicate GarageBand
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Pot
Parent class for all potentiometers
LinearPot
A B type linear potentiometer for adjusting pedal parameters (manages AudioParam)
LogPot
An A type logarithmic potentiometer for controls like volume and overdrive, which are typically logarithmic.
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Footswitch
Toggles the pedals or on off with a true bypass mechanism — works like a 3PDT switch.
Led
Works alone or coupled with a Footswitch, shows the status of the pedal or anything you like (i.e., tempo)
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Demo time!
thank you!
Let's keep in touch!
Armagan Amcalar
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slides: tr.im/gdgb-rnr
demo: pedals.io