Audio Systems: Mono-To-Stereo Remixes, piper at the gates of dawn, piper at the gates

Question
Hi Parke
I'm wondering if you might know a little bit about the "simulated stereo" mixes that were common in the late 1960's; for example Sgt Peppers or Pink Floyd Piper at the Gates of Dawn.  I understand the concept of taking two mono recordings and synching them and EQ'ing them discreetly to either of the two stereo mixdown tracks.  I also understand how adding delay can be used.  It also sounds to me like what I would call "active panning" was used in those types of mixes to get voices or other doodles and SFX to move from side to side. Despite knowing that and having done a lot of 4 track recording and post producton myself (which was usually mono with a little bit of stereo panning sprinkled on top during post)---It seems to me that the engineers might have used other techniques as well. So my question boils down to this:  Do you know if most of the old mono-to-stereo re-mixes only used the techniques I mentioned or were there other things that they did in addition to those techniques and if so what were they?  No biggie, but I've just always been curious about that.  Thanx-----Jim

Answer
Hi Jim,

 I know the theory of "simulated stereo" and understand the fundamentals to be exactly as you have stated.  
  There was occasionally some EQ work to get two live tracks to match more closely... sometimes with even the most carefully matched stereo mic pairs you can't do anything to combat uneven room acoustics.
  There were some early experiments with Binaural mic'ing off-and-on in the 60's, but "stereo recording" was in its infancy and in general there just wasn't quite the technology availible in the studios for much vareity in the methods until a bit past the dawn of "simulated stereo" or "dual mono".

  That being said, I did spend some time shadowing a gentleman named "Robert Parker" (RIP) who used to work with Public Radio International in the 90's remastering/restoring old wax 78's to stereo (or 5.1) in the digital realm.
 
  His equipment was half restoration lab, have pro-tools postproduction studio, and he more or less divided his work into three phases:

1) Restoration:
Transferring the original recording and de-essing/de-popping)

2) Isolation/voicing:
Using various DSP tricks (phasing, parametric EQ, active canceling algorithms, etc.) to isolate certain voicings (usually 8).
-In this case, "voicings" were intended to highlight or isolate certain sections of Swing-jazz orchestras (the woodwinds, the brass, bass, the pianos, percussion, voice, ...)

3) Remastering:
Each "voicing" or track would be assigned a certain subtle reverb tail, group delay, phase, and pan based on historical records of how the band had set up for the recording or had traditionally been arranged on stage by the leader.  
Then the tracks would be combined with the correct amount of pan to form a stereo image.

Hope you find that as interesting as I did.  I'm happy to elaborate more (as much as I can) but I can't go much further without speculation - I have no idea what algorithms he had developed and since he's passed on, to my knowledge, his techniques and work have scattered to the winds.


Another intersting side-note would be the use of the Decca Tree for recording.  Originally the entire mic array would be mixed live down to a mono recorder, but with the dawn of the 8-track, sometimes studio recordings with an 8-segment decca tree were sent straight to an 8-track reel-to-reel (one mic per channel).  

As a sort of odd form of post-production, the engineer could then individually EQ and taper each mic individually to mix-down, or pan a suble L/R stereo image if the act justified stamping out stereo on vynil.

I have long thought that if any of those 8-track masters are in good enough condition, it would make a compelling research project to develop an algorithm to remaster those tracks to 5.1 or 7.1 - the acoustic information is certainly there.

You may enjoy reading up on the life of Joe Meek, there are plenty of good books out there about his "life" and methods around this period that you might find interesting (assuming you've already plumbed the depths of Abbey Road and "that other Sir George").