Sony 7 manual Generating audio with frequency modulation

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Generating audio with frequency modulation

Sound Forge’s FM Synthesis feature can be used to create complex sounds from simple waveforms using frequency modulation (FM).

In frequency modulation, the frequency of a waveform (carrier) is modulated by the output of another waveform (modulator) to create a new waveform. If the frequency of the modulator is low, the carrier is detuned slowly over time. If the frequency of the modulator is high, the carrier is modulated so quickly that numerous additional frequencies (or sidebands) will be created.

Using the FM Synthesis tool, up to four waveforms (operators) can be used in a variety of configurations. Depending on the configuration, a waveform can be a carrier, a modulator, or a simple, unmodulated waveform.

FM Synthesis dialog

Generating a waveform

1.From the Tools menu, choose Synthesis, and choose FM from the submenu. The FM Synthesis dialog appears.

2.Specify the length (in seconds) of the generated waveform in the Total output waveform length box.

3.Use the Configuration slider to configure the arrangement and number of operators used to generate the waveform. For more information, see Specifying the number and arrangement of operators on page 143.

4.Modify individual operators as needed. For more information, see Modifying an operator on page 143.

5.From the Insert waveform at drop-down list, choose a position to determine where the generated waveform is placed in the file.

6.Click OK.

EDITING, REPAIRING, AND SYNTHESIZING AUDIO CHP. 9