Finally let me touch upon quadraphonic recordings as they appeared on vinyl records. There was no industry standard when it came to defining exactly what quadraphonic was, so many different types of quadraphonic techniques and their resulting consumer products appeared on the market.
CD-4 Quadraphonic was a true 4 channel recording, but since it used frequency multiplexing these are of little use on a standard stereo since you cannot hear the 3rd and 4th channels (Note: these were encoded in frequencies above the audible range and decoded into the audible range upon playback.)
However, SQ quadraphonic recordings are of interest because you can hear all of the tracks when played on a typical stereo system. Many times SQ quadraphonic records had very different mixes of a recording as the engineers went back to the studio multi-tracks to create an all new version of a recording. These can be very entertaining to anyone who is very familiar with the standard stereo version of the recording. Columbia records was particularly good about creating new versions;
- Sly and the Family Stone’s albums in SQ quadraphonic are quite different.
- Also look for Pink Floyd’s Dark Side of the Moon in SQ quadraphonic as it is noticeably different.
That is not to say that it is better or worse, but it is definitely different.
One last thought about mono and stereo is in order. It is my opinion that an optimal stereophonic sound field that is realistic of an actual performance is just a subtle difference away from a pure monophonic recording.
In other words a little stereo effect goes a long way to my ears. And if you are more focused on the performance rather than as entertainment then I would go as far to say that the stereo effect can detract from the performance.
Again, it is just my opinion, but listening in mono allows the listener to concentrate solely on the performance, which is why so many musicians prefer mono over stereo.