Specifications

Chapter 8: DINR 69
4 Click the Fit button to fit a Contour Line to it.
5 In BNR’s Spectral Graph, Command-drag
(Macintosh) or Control-drag (Windows) to
make a selection. Select points where the high-
frequency noise components are most evident.
In general, the flatter areas of the Spectral
Graph, are better, since they represent quieter
areas where there is probably less signal and
more noise.
6 Click the Auto Fit button. DINR computes a
generic noise curve and corresponding Contour
Line based on your selection. If you want to re-
move the selection in the Spectral Graph Dis-
play, Command-click (Macintosh) or Control-
click (Windows) once.
7 Follow the steps given in the previous section
removing the noise using the NR Amount slider
and other controls.
8 Since the Contour Line is not based entirely
on noise from your audio file, you may also
want to edit its envelope in order to fine-tune
the noise reduction. See “Editing the Contour
Line” on page 69.
Editing the Contour Line
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 au-
dio 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 sig-
nal loss, the Contour Line should be above any
noise components, but below any signal com-
ponents. To fine-tune the broadband noise re-
duction, try moving individual breakpoints at
different locations along this line to find out
which segments remove the noise most effi-
ciently. For more dramatic results, try moving
the entire Contour Line upwards. One drawback
of the latter technique is that it will typically re-
move a considerable amount of signal along
with the noise.
Remember that high frequency noise compo-
nents 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 win-
dow. 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.
2 Select Options > Loop Playback.
3 Begin playback.
Noise components on the Spectral Graph