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A trailing tilde marks Pd signal objects, distinguishing the audio level from the control level

Concept L1Foundations F · Live coding: musicB · Sound design & synthesis

Pd runs on two distinct levels. The control level (a.k.a. message domain) carries discrete control data - numbers and symbols - sent by clicks, number boxes, and messages. The signal level carries continuous audio. Every object that produces or accepts audio signals has a tilde () appended to its name (osc, dac~, lop~); objects without a tilde work only with control data. The two cable kinds even look different (thick for signal, thin for control). The global ‘compute audio’ switch turns signal processing on or off, letting you program without generating sound. Confusing the levels - e.g. wiring a control number straight where a signal is expected - is a common beginner error.

Examples

osc~ (signal: makes a tone) vs + (control: adds two numbers). dac~ has a tilde because it accepts an audio signal; a number box does not.

Assessment

Given a list of objects (osc~, metro, dac~, +, lop~), sort them into signal vs control and state the rule you used.

Prerequisites — understand these first

Don't confuse with

Sources

“all objects that produce signals or that work with signals as an input (input = that which goes into an inlet; output = that which comes out of an outlet), have a tilde ("~") after their name; other objects don't have this!”
pd-tutorial.com

Taught in modules

Unlocks (1) — atoms that build on this