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.
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.
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.
Comments, suggestions and bug reports are welcome and should be sent to email@example.com
This page last modified 2003-07-28 - Copyright © 2000-2003 ACE