Generating audio with waves
The last section mainly uses prerecorded sound for playback. We can generate original sound from Pure Data itself. We hear sound from our computers because the speakers transmit sound waves through the air. In Pure Data, we can create a sound wave with audio objects. The digital sound wave will play through the digital-to-analog converter and become the analog vibration of the speaker membranes.
In Pure Data, we create simple waveforms, such as sine wave and sawtooth wave. We shall see the waveform displays in the following patches. When we hear a piece of sound, we identify three properties: the first one is the loudness or amplitude, the second one is the pitch or frequency, and the third one is the quality or timbre. The first two properties are easy to understand. Acoustic musical instruments or our voice usually do not contain only one frequency. A note usually contains a number of different frequencies with different amplitude. They are the overtones. Usually...
