MUMT 307

Outline

• Check these out:
• Soundkeep Synth
• Whiteboard Drums
• BBC Radiophonic Workshop
• Assignments
• Spectrum Analyzer
• Delay line
• Echo
• Make Echo work with mic input (lab)
• Waveshaper
• Improve on the waveshaper demo (lab)
• Make http://synth.soundkeep.com work in Firefox (lab)

MUMT 307

Spectrum Analyzer

• Frequeny domain vs time domain representations of signals
• Web Audio API AnalyserNode
• At SF of 44,100 samples / sec
• fftSize: 2048 --> 46.4 ms resolution; bin = 21.53 hz wide
• fftSize: 256 --> 5.8 ms resolution; bin = 172.26 hz wide
• Spectrum display
• Spectrum and wave display
• requestAnimationFrame: If you are interested in animation, check this and watch the video

MUMT 307

Delay lines

• DelayNode is an AudioNode
• To create a DelayNode use: createDelay(maxDelayTime)
• where maxDelayTime is an optional parameter
• DelayNode has delayTime attribute, which is an AudioParm
• Delay line demo
• Delay line w/ Mic input
• Firefox: works; Chrome: only from a server; Safari: not supported; IE:?

MUMT 307

Echo

• Echo is a delay line with its output feeding back to its input
• Echo demo

MUMT 307

Lab #1

• Make Echo work with Mic input
• Use Delay with Mic Input as a model
• If your code works on Firefox, uplaod it to the music sever website and make it work on Chrome

MUMT 307

Waveshaper

• Type of a distortion synthesis
• `y(t) = f (x(t))`, where `f` is a transfer function
• The transfer function is typically a lookup table
• WaveShaper with audio input

MUMT 307

Lab #2

1. Make a WaveShpaer with the Oscillator input
2. Be able to change the waveform
3. Be able to change the frequency
4. Be able to change the gain into the waveshaper
5. Be able to change the gain out of the waveshaper
6. Change the transfer function. Some examples here.

MUMT 307

Lab #3

• Make Soundkeep Synth work in Firefox

MUMT 307

Reverb

• Convolution
• Revereb Demo