The Audio
Mixer Help Page
This is the help page for the Audio Mixer tool,
which is part of the KarVCD toolset. The purpose of this tool is to mix two or
more WAVE files into one, controlling the contribution of each file to the
overall result.
The Audio Mixer Dialog
Let us take
a look at the Audio Mixer fields and buttons:
Most of the
window area is occupied by 5 identical groups of controls: Four of them
describe the input WAVE files and the remaining describes the output WAVE file.
The only difference between these groups is the Offset control, which in the
case of the Output group is replaced by the Separator control. Each group has
the following elements:
¨
File. This field shows the name of the WAVE file
associated with the group. For an input group this will be the name of the
input WAVE file to mix, for the output group this is the name of the WAVE file
that will receive the sum of all the input files.
¨
Clear. This button clears the FILE
field.
¨
Browse. This button allows you to select a
file and associate it with the group. For an input group this must be an
existing file, for the output group this is the file that will be created as
the result of the mixing process.
¨
Offset. This is a set of controls that let
you position the offset for an input file. It includes an edit control and a
thumbwheel. You can either edit the offset value directly in the edit control
or use the thumbwheel. The offset value can be positive or negative, is
expressed in seconds and can have decimal values.
¨
Separator. This is a set of controls that let
you define the amount of silence that will be appended to the end of the output
file. It includes an edit control and a thumbwheel. You can either edit the
separator value directly in the edit control or use the thumbwheel. The
separator value is always positive, is expressed in seconds and can have
decimal values.
¨
Volume. This slider controls, in the case
an input file, the relative contribution of that file to the overall output
sound; it is expressed as a percentage and ranges from 0 to 100%. For the
output file it specifies an extra amount of amplification or attenuation of the
sound; it ranges from –50% to +50%; positive values mean amplification,
negative ones imply attenuation.
¨
Pan. This slider controls the position of a file
in the stereo field.
The Mix
process group of controls include a progress bar that shows the progress of
the mixing process, a field that shows the time already done versus the total
processing time, plus the following elements:
¨
Apply effects. This check box controls whether
the sum of the input files goes directly to the output file or passes through
the sound effects unit.
¨
Trim silence. This check box will cause the
silence at the beginning and end of the output file to be removed.
¨
Normalize output file. This check box directs the program
to rescale all the values in the output file so that all the dynamic range
available is used.
¨
Preview. This button lets you hear what the
mix will sound like, without actually creating the output file.
¨
Mix. This button initiates the mixing process.
¨
Stop. This button aborts the mixing process.
¨
Play. This button lets you hear the output file
that was created during the mixing process.
Follows a
description of the remaining buttons:
¨
Effects. This button will open the Sound
Effects Dialog, where you can set the parameters that control sound effects
processing.
¨
Help. This button shows you the file that you are
now reading.
¨
Reset. This button sets all the fields in
the dialog to their initial values.
¨
Close. This button closes the Audio Mixer
Dialog and returns you to the Main Window.
Operation
The operation of the Audio Mixer is
straightforward: You select one or more input files, set the output file, set
the several options available and hit Mix.
If you just
want to hear what the mix will sound like, without actually creating the output
file, you hit Preview. While the mix is playing in this mode, you can
adjust the sliders that control the volume and the pan position of each channel
and hear the result immediately.
The sum of
the input files can go directly to the output file or can pass through the
sound effects unit. This is controlled by the Apply effects check box.
While in Preview mode the sound effects will not be applied. To edit the
sound effects parameters hit the Effects button. This will open the Sound Effects Dialog. For a description of the
available sound effects see Sound Effects Overview.
The Offset
control lets you precisely align the input files relative to each other so that
they will be added synchronously to the output. The offset value can be
positive or negative. A positive value means that a chunk of sound at the
beginning of the file will be skipped. A negative value means that a chunk of
silence is added at the beginning of the file.
The Offset
control is also useful to remove the “beat marks” that appear at the beginning
of some MIDI or KAR files. These marks are very useful in some circumstances
but you would not want those in a CD track. To remove the “beat marks” adjust
the offset to a positive value corresponding to the duration of said marks.
The Separator control allows you to append
silence to the end of the output file. This is useful when you are preparing
files to write to an Audio-CD, to serve as a track separator. Some CD-burning
programs let you add the separator during the burning process, others don’t.
You can mix
files of different lengths. The output file will be as big as the biggest input
file.
When you
add or remove input files, the program automatically adjusts all the volume
sliders assigned to inputs so that all the inputs contribute equally to the
overall result and making sure that there is no clipping. You can change that
manually to reflect your mixing preferences. In Preview mode you can do that in
real time, while the mix is being played.
This
Normalize output file feature is
very useful when you are making an Audio-CD with several files, to make volume
level consistent throughout the whole CD. Otherwise you would need to adjust
the volume from track to track.
Besides
its main function of mixing files, this tool can also be used to make
specialized processing over a single file such as normalization, adding silence
at the beginning or the end of the file, removing silence and applying sound effects.
In this case you select just one input file, the output file and set the
options corresponding to the processing that you intend to do. After the mixing
process, the output file will have the input sound with the modifications
applied.
When you close
the Audio Mixer Dialog with the Close button, the program will set the
output file as the WAVE file in the main window. Before doing this, the program
makes sure that the output file does in fact exist.
Feedback
Comments, suggestions and bug reports are welcome and should be sent to fadevelop@clix.pt
This page last modified 2003-07-28 - Copyright
© 2000-2003 ACE