Real stereo, loudness wars and a fork in the road

Having been an avid music lover and audio enthusiast since childhood, having done pro audio work in a number of studios for over a decade and having read all the books and journals on the subject I could find, I was not prepared for that experience in 1988 when I heard stereo for the first time.  Apart from the unparalleled joy the experience elicited (as in “Who knew audio playback could be this realistic?”), it engendered a great deal of thought, including the realization that what I’d heard until then was essentially dual mono, synchronized but separate programs, not the coherent and convincing whole possible with real stereo.

Now that I’d learned how proper setup of stereo loudspeakers allowed the speakers to better “disappear” and (with recordings containing the information) leave behind a three dimensional sense of the performers and the space in which they played, I saw new possibilities for the recordings themselves.

In my last experiment with direct to stereo recording, I had considered the relationship between the positions of the two microphones during recording and the two speakers during playback.  I thought there might be some reciprocity between the both ends of the chain.  To more closely emulate the space between playback speakers, I used a 6 foot (~1.8 meter) spacing between the microphones.  Considering the time element, my reasoning was that the time a signal took to get from left mic to right mic should match the time it took to travel between the speakers in the listening room, hoping the symmetry would get me closer to “being there” when listening to the result.  While that recording avoided the hole-in-the-middle common too many recordings made with two widely spaced microphones, I found that instruments positioned slightly off center during the recording session had a tendency to “pull” to the near speaker on playback.  (I wrote an article called Recording in Stereo about my experiences in these tests.  A highly abridged version follows herein.)

How to get stable stereo without introducing the time-based distortions (i.e., “ghost” images) that would result from adding more microphones?  I decided to try some iterative experiments in the studio, recording my speaking voice as I walked around in front of the microphones.  Each test was repeated with the spacing between microphones changed slightly.  I started with my original 6 foot spacing, announcing my position to the microphones, for example “3 feet left of center, 2 feet left of center, 1 foot left of center, center, 1 foot right of center, 2 feet right of center”, etc.  Next, I did the same thing with the mics a bit closer together, then another test with the mics still closer together and so on until the mics were 7 inches (~18 cm) apart, matching the spacing between a typical listener’s ears.

To quote the article cited above, “On playback, I paid particular attention to the just off center area that had proven problematic with the 6 foot spacing.  Somewhere around 15 inches (~38 cm), things seemed to gel.  All the qualities I liked were there with considerably less vagueness in the image.  My long held belief in recording with omnis spaced at 6 feet was being revised.”

“I started researching just how it is our brains perceive stereo and the cues required for localization (our ability to determine where a sound is coming from).  What I learned was our brains use three types of cues to determine localization:  intensity, time and frequency [specifically, differences in intensity, time and frequency between the sounds arriving at each of our ears].  Then it dawned on me that if nature could have gotten by with fewer cues, it would have done so.  I began to consider what was needed to supply all three types of cues in a stereo recording.”

The last step was the design of an absorbent baffle to be placed between the microphones.  Again from the article, “I’d found my way to record in stereo, incorporating all three types of cues nature uses to inform us of where a sound is coming from:  intensity, timing and frequency.  The timing information provided by the omnis benefited from the disk-shaped baffle which provided increased intensity differences between mics as well as frequency discrimination between mics.”

All the while these experiments went on, I was doing mastering work for a number of labels.  A disturbing trend was making itself evident, in that all too many of the A&R folks and producers at the labels were talking more and more about loudness.  I can recall one “name” producer who asked me “How much do you usually raise the level of tapes that come in here?  We do 6 dB.”  I wasn’t sure how to reply to his query because my experience had long ago taught me that some tapes require the level to be dropped, not raised, if one wanted to get the best possible results from the master.  Other record folks were requesting a “balls to the wall” sound (ouch!).  These were the foundations of the so-called “Loudness Wars”, an arms race of sorts, where folks wanted their record to be louder than everyone else’s.  There were folks who evaluated my mastering work with VU meters and not with loudspeakers!  “If it goes in the black, you lose.”  (For more on the subject, see my article Declaring an end to the loudness wars.)

At this point, I had to stop and ask myself why I became an audio engineer and just what I sought to accomplish in my work.  I knew for sure that the weaponizing of sound and music was not among my goals.  What a strange dichotomy.   As I sought to create recordings that sounded more like life and had more dynamic range, the larger trend in the industry was to eviscerate dynamics, seeking ever greater quantity without regard for the cost in quality.

Where the best records of “loud” music invite the listener to turn up the playback volume, casualties of the loudness wars cause physical discomfort.  My personal take is that the loudness wars have played a large part in the decline of the record industry.  Highly compressed sound brings about a stress response in the listener.  Joe and Jane Average may not be consciously aware of this but as a result, they don’t buy nearly as many records as they used to and they don’t listen to the ones they do purchase as many times as they used to.  New records are supposed to bring pleasure, not a “fight or flight” response.

Having considered my reasons for being an audio engineer, I decided to take a two-fold approach.  First, those making mastering inquiries are asked how important final level is to them.  The many benefits of achieving loudness with the playback volume control, as opposed to recorded level, are explained.  Those whose prime interest is in the quality of the music and sound tend to become clients.  Those who really want loud records are gently referred elsewhere.  (I know many mastering engineers say they prefer not to squeeze the life from their clients’ recordings but consent to do this because they need or want the work.  That is a personal decision each individual must make for themselves.)  Second, my fascination with making records that sound like music itself—as opposed to simply sounding like records—was on the rise.  While mastering can be very rewarding, I came to understand that 90-95% (or more) of any recording’s ultimate sound quality has already been determined by the time the signals are leaving the microphones.  In other words, the overall quality is already there (or not) as soon as the signals enter the mic cables.  Everything else is just relatively minor adjustments to the overall picture.

Having rented time in a few different studios to do my mastering work, I started thinking of designing a space for myself.  The idea was more than appealing since I could have complete control over the acoustic design and gear selection.  Of course, monitoring, as always, was the prime concern.  In addition, it was time to assemble a recording kit of my own and lose the dependence on what I could borrow or rent.  And to provide a vehicle for distributing the new recordings, I was thinking about a new kind of record label.

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