Application Example: Cross-Synthesis

Cross-synthesis is generally concerned with impressing the spectral envelope of one sound on the flattened spectrum of another.

Let's call the first signal the ``modulating'' signal, and the other the ``carrier'' signal.

A classic example is for the modulator to be voice and the carrier to be a spectrally rich sound such as wind, rain, creaking noises, or musical instrument sound.

Example: A ``talking organ''

• ``Carrier''
• ``Modulator''
• Modulated Carrier

Commercial ``vocoders'' used as musical instruments consist of a keyboard synthesizer (the carrier sounds) with a microphone for picking up the voice of the performer (to extract the modulation envelope).

More Examples:

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Voice ``modulator''

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Cow ``carrier''

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Voice-modulated cow

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Gong ``carrier''

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Voice-modulated gong

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Airplane ``carrier''

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Voice-modulated plane

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Creaking ship's mast ``carrier''

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Voice-modulated creaking mast

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Same with modified spectral envelopes

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Previous example with modified spectral envelopes 2