Modulate sine tones.

[GlenLivet21]

Is it easily possible to generate a sine tone and then apply am and fm modulation to it? Lets say I want a 500 hz tone that vibrates between 450 and 550 hz with 5 hz fm and am. How would I go about in audacity to do this? One hour googling gave no answer.

[GlenLivet21]

How to fm and am modulate a sine tone?

[steve]

Modulation takes two signals. Are you wanting to modulate two sine tones, or one sine tone with some other signal?

[steve]

Topics merged.

[GlenLivet21]

Modulation takes two signals. Are you wanting to modulate two sine tones, or one sine tone with some other signal?

I want to modulate one sine with another sine. Both am and fm.

[steve]

Amplitude modulation is easy. You just "multiply" the two tones. You can do this using the Nyquist Prompt effect (http://manual.audacityteam.org/man/nyquist_prompt.html).

To amplitude modulate any selected audio with, say a 5 Hz sine tone, use this code:

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(mult *track* (hzosc 5))

For frequency modulation, it is easiest to generate both the carrier and the message. For example:
"I want a 500 hz tone that vibrates between 450 and 550 hz with 5 hz"

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(hzosc (sum 500 (mult 50 (hzosc 5))))

[steve]

For AM, generating both the carrier and the message:

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(mult (hzosc 500)(hzosc 5))

[steve]

A slightly different (a bit more complex, but more "normal") version for AM:

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(mult (hzosc 500) 0.5 (sum 1 (hzosc 5)))