Download the JAVA-Application (version 0.6 - 23/01/2010) CIPAudioPlayer.zip (12kByte) which works for Windows, Mac and Linux.
If you don't have the JRE (JAVA Runtime Environment) installed then you'll get it here: http://www.java.com/download/manual.jsp
Why three channels for stereo?
In a normal stereo setup the spot where the stereo image really creates the best sound stage is very small. By calculating a third signal for a center speaker it is possible to enhance the stereo soundstage for more than one listener.
The center signal gets calculated by applying a linear matrix which decodes the left and right stereo channels into the center channel.
The valid range for C (Center-Factor) is -1 to 1, but the CIPAudioPlayer just uses a range of 0 to 1.
Let's calculate the resulting vector by choosing significant values for C:
C=0 -> Lo = Li | Ro = Ri | Co = Li + Ri -> The left and right channels stay untouched, whereas the center channel is the sum of the right and left channels (mono signal).
C=0.5 -> Lo = Li - 0.5 * Ri | Ro = Ri - 0.5 * Li | Co = 0.5 * (Li + Ri) -> The left and right channels get reduced by half of their mono signal, whereas the center channel gets increased by that part of the signal.
C=1 -> Lo = Li - Ri | Ro = Ri - Li | Co = 0 -> The left and right channels are now without any mono signal. The center channel becomes silent.
Useful values for the Center-Factor are around 0.5 - 0.7 which enhances the stereo image just with the right amount of a mono center signal.
The Center Image Processor - Audio Player
What does the program do?
The CIPAudioPlayer plays back PCM 16Bit/44.1kHz wav-files through the main speakers and center speaker by using different sound-mixer (sound-cards).
As an example you could connect the main and center signal to the pre-inputs (external decoder inputs) of a 5.1 AV-Receiver/Amplifier to apply the signal to the three front speakers (left, center and right).
The CIPAudioPlayer has been developed in JAVA to assure maximum cross platform compatibility for Windows, Mac and Linux. There is no need for any installation, just unzip and launch the JAR-File.
As a pre-condition you need to have the JRE (Java Runtime Environment) installed which you can download here: http://java.com/download/manual.jsp
As described above the Center-Factor should be around 0.5 to have the best three channel stereo sound stage.
Selecting the checkbox activates transparent playback without applying the decoding matrix to allow comparison between 3 channel and 2 channel stereo.
Sets the volume of the main speakers (left & right).
Changes the volume of the center speaker.
Main and Center Sound-Mixer/Card:
Here you need to select the sound-mixers (sound-cards) you want to use for the main and center speakers to be connected to the dedicated amplifier inputs.
Disclaimer and License:
This Software is provided "as-is", without any express or implied warranty.
In no event will the author be held liable for any damages arising from the use of this software.
Permission is granted to anyone to use this software except for commercial use.
Please contact me (Stephan Hotto) if there is a wish for a commercial implementation.