Digital Reprocessing
Haeco-CSG processing can be reversed through digital audio workstation software by digitally re-rotating phase of the right channel back by the correct number of degrees.
Adobe Audition is able to remove the effect using the Graphic Panner tool (the Automatic Phase Correction tool is unable to accurately do this) by manually selecting the "Phase -90 degrees" preset. The "Auto Center Phase" and "Learn Phase" features will also work, but are not recommended. There are sometimes slight offsets caused by various mixing effects and, to a lesser extent, tape-head misalignment; studio reverb or naturally decaying reverb is a prime example. As a waveform decays in a large room, it naturally changes phase. In Auto Center phase, this is (generally) shown as the upper frequencies making a drastic change. Tape head misalignment (azimuth) also will cause a phase change in upper frequencies. One should be aware of this when attempting to remove Haeco processing and not use auto-phase options. Azimuth alignment adjustment tools can however be used AFTER Haeco has been removed.
The "Stereo Tool" plug-in used in conjunction with Winamp is also able to (mostly) reverse the effects of Haeco-CSG. To do this enable "Stereo Image Processing" option and adjust the "Angle" setting right to 90 degrees. By adjusting the Winamp plug-in settings under the "Preferences" tab to "out_disk" it is also possible to capture the reprocessed digital audio to a wave or mp3 file.
One can also use a simple channel mixer found in most workstations to do a simple correction. By having each channel contain 75% of itself and 25% of the other channel, the "blended" result will be mostly in phase. This, however, can cause the stereo separation to be diminished by a slight degree.
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