One of the most effective ways to fine-tune the effects of broadband noise reduction is to edit the Contour Line. The Contour Line treats audio below the line as mostly noise, and audio above the line as mostly signal. Therefore, the higher your move the Contour Line upwards, the more audio is removed.
To maximize noise reduction and minimize signal loss, the Contour Line should be above any noise components, but below any signal components. To fine-tune the broadband noise reduction, try moving individual breakpoints at different locations along this line to find out which segments remove the noise most efficiently. For more dramatic results, try moving the entire Contour Line upwards. One drawback of the latter technique is that it will typically remove a considerable amount of signal along with the noise.
Remember that high-frequency noise components are typically more evident in the flatter, lower amplitude areas of the Spectral Graph. Try editing the Contour Line in these areas first.
To hear the changes you make to the Contour Line in real time:
1 Select the target audio in Pro Tools’ Edit window. Make sure the selection is at least a second or two in length. If the selection is too short, you won’t be able to loop playback.
1 To move a breakpoint, click directly on it and drag it to the desired position. Moving a breakpoint higher increases noise reduction at that range. Moving a breakpoint lower decreases noise reduction at that range.
2 To move multiple breakpoints, Control-drag (Windows) or Command-drag (Mac) to select the desired breakpoints. Click the appropriate Move Breakpoint button (below the Spectral Graph) to move the selected breakpoints in 1 dB increments. Control-Shift-drag (Windows) or Command-Shift-drag (Mac) to extend your selection.
3 To move the entire Contour Line, Control-drag (Windows) or Command-drag (Mac) to select the entire range. Click the appropriate Move Breakpoint button (below the Spectral Graph) to move the selected breakpoints in 1 dB increments. The higher you move the Contour Line above the noise signature, the more noise is removed.
4 To create a new breakpoint, click on the Contour Line.
5 To delete a breakpoint, Alt-click (Windows) or Option-click (Mac) the breakpoint. As long as you click and hold the mouse, you will delete all breakpoints that the cursor passes over.