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changing the pitch. This will change
the length of the selection.
Compressor - compresses the
dynamic range of the selection so
that the loud parts are softer while
keeping the volume of the soft parts
the same. You can optionally
normalise the recording afterwards,
resulting in the entire piece having
higher perceived volume.
Echo - very simple effect that
repeats the selection with a decay,
sounding like a series of echos.
This effect does not change the
length of the selection, so you may
want to add silence to the end of
the track before applying it (using
the Generate Menu).
Equalization - Boost or reduce
arbitrary frequencies. You can
select one of a number of different
curves designed to equalize the
sound of some popular record
manufacturers, or draw your own
curve.
Fade In - fades the selection in
linearly
Fade Out - fades the selection out
linearly
FFT Filter - similar to Equalization,
lets you enhance or reduce arbitrary
frequencies. The curve here uses a
linear scale for frequency.
Invert - Flips the waveform
vertically, the same as a phase
inversion in the analogue domain.
Noise Removal - This effect lets
you clean up noise from a recording.
First, select a small piece of audio
that is silent except for the noise,
select "Noise Removal", and click
on the "Get Noise Profile" button.
Then select all of the audio you
want filtered select "Noise
Removal" again, and click the
"Remove Noise" button. You can
experiment with the slider to try to
remove more or less noise. It is
normal for Noise Removal to result
in some distortion. It works best
when the audio signal is much
louder than the noise.
Normalize - allows you to correct
for DC offset (a vertical
displacement of the track) and/or
amplify such that the maximum
amplitude is a fixed amount, -3 dB.
It's useful to normalize all of your
tracks before mixing. If you have a
lot of tracks, you may then need to
use the track gain sliders to turn
some down.
Nyquist Prompt - for advanced
users only. Allows you to express
arbitrary transormations using a
powerful functional programming
language. See the Nyquist section
of the Audacity website for more
information.
Phaser - the name "Phaser" comes
from "Phase Shifter", because it
works by combining phase-shifted
signals with the original signal. The
movement of the phase-shifted
signals is controlled using a Low
Frequency Oscillator (LFO).
