User guide

Chapter 22 Removing Silent Passages From Audio Regions 551
Using Strip Silence
This section outlines the steps, and parameters, involved in the Strip Silence process.
To remove silent passages from a selected region:
1 Do one of the following:
 In the Arrange area, choose Audio > Strip Silence (or use the Strip Silence key
command, default: Control-X).
 In the Audio Bin window, choose Options > Strip Silence (or use the Strip Silence key
command, default: Control-X).
2 In the Strip Silence window, set the following parameters by using the mouse as a
slider, direct numerical entry, or clicking on the up and down arrows.
 Threshold: Use this to define the amplitude level (shown as a percentage) that a
passage must exceed, in order to be defined as a region. In terms of the number and
length of regions created by the process, this is the most important parameter. As a
general rule: a higher Threshold value leads to numerous short regions. Low values
create fewer large regions.
 Minimum Time to accept as Silence: Use this to define the length of time that a
section must be below the Threshold value, before it is considered a gap. Very small
values tend to increase the number of regions, because even short dips in amplitude
are interpreted as silence. Higher values prevent sections of audio from being
interrupted by fluctuating amplitudes.
 Pre Attack Time: You can add a defined amount of pre-roll to the beginning of all
regions created by the Strip Silence process, if desired. High threshold values prevent
any amplitudes with slower attack times from being chopped. This function is useful
for non-percussive material such as vocals, wind instruments, strings, and so on.
Overlaps are permitted—the pre-delayed start point of a region can extend back to
the end of the previous region—but only if the Threshold value is not exceeded. The
Pre Attack Time doesn’t affect the anchor position, which means the absolute
position of the audio data (in the project) is retained.