SOUNDLAB: Lazy signal combinators
Max Rottenkolber <max@mr.gy>
May 29, 2013

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Table of Contents
1 HOW DOES THIS WORK?

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2 SIGNAL COMBINATORS

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3 OVERVIEW OF THE LIBRARY

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4 USING SOUNDLAB

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1.1 Whats a signal? . . . . . . . . . . . . . . . . . . . . . .
1.2 Recording sound . . . . . . . . . . . . . . . . . . . . . .

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1 HOW DOES THIS WORK?

The workow.

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1.1

Whats a signal?

The sum of sines, e.g.

Sine.

Sine noise.
A function which maps time to amplitude (-1..1) e.g. #'SIN.
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1.2

Recording sound

Sampling simplied.
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2 SIGNAL COMBINATORS
(defun chord (&rest signals)
(lambda (x)
(/ (loop for signal in signals
sum (funcall signal x))
(length signals)))
(divide (apply #'add signals)
(flatline (length signals)))

Implementing CHORD.

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(FUNCTION (&REST (FUNCTION (REAL) REAL))
(FUNCTION (REAL) REAL))

A common interface for time and amplitude modulation.

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3 OVERVIEW OF THE LIBRARY

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Library overview.
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4 USING SOUNDLAB

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What we are going to do.
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Voice envelope.

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Phaser envelope.

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