mcfredrick / bandlab-wac

Web Audio Conference 2017 – Tutorial

Designing and deploying sample-based instruments

In this tutorial we will run through the process of creating a sample based MIDI instrument utilizing both Web Audio and Web MIDI. We will start by broadly addressing the sound design concepts used to create the individual samples and then techniques for increasing download speed using infinite looping and variable speed playback. We will then define the instrument’s basic user interface.

In the second half of the session we will address both real-time audio effects such as non-convolution reverbs and MIDI effects such as a simple arpeggiator and chord generator.

What to bring

Your laptop, with Node.js installed, headphones and a mood for jamming!

Duration

90 minutes

Presenters

John Ivers, Laurent Le Graverend, Gilles Piou

Getting started

To start the development server:

npm install
npm start

Tutorial

Sampler

1. Bind keyboard events
2. Play sample files

Velocity envelope

1. Connect a gain node
2. Pass velocity parameter

Pitch-shift

1. Use pitch-shift formula
2. Parse soundbank JSON

Infinite sustain

1. Include crossfade to existing audio buffers
2. Use Web Audio loop feature

Harmonizer

1. Call harmonizer functions when playing notes on the sampler

Effects

1. Connect freeverb effect node to the sampler output