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Generating a 440 Hz tone

To create a specific 440 Hz tone, follow these steps. You can vary the length, use more channels, or change the frequency to a different desired value (figure 19.2).

Figure 19.2: Use Audio →Render effect to set render parameter values and then that effect can be varied.

1. Make sure there is an armed audio track on the timeline, get into Cut and Paste mode, and highlight a selection or define In/Out points where you want to insert the audio tone.
2. Go to Audio → Render effect. Rendered effect usage is described in Effect Plugins. This brings up a menu where you will select the desired effect which in this case is F_aeval. Also Select a file to render to, a File Format, and Insertion strategy of Paste at insertion point.
3. Click on the green OK checkmark which will popup the F_aeval effect so that you can set the parameters.
4. Highlight the exprs option and key in a specific audio filter expression which for 440 Hz would be: sin(2πt×440). Then hit the Apply button.
5. Next when you hit the green OK checkmark on the CINELERRA-GG: Effect Prompt popup, you will have your 440 Hz tone on the timeline plus in the select file that you chose to render it to.
6. To use 2 channels instead of 1, in the F_aeval menu highlight the channel_layout option and change that to 1C|2C instead of the usual default of 1C.