BitPerfect user John Bacon-Shone correctly pointed out in
response to my recent musings on DSD that the SACD format delivers a huge
amount of music in surround sound format, which is a particular boon to
classical music listeners. And not many
people are aware of that.
Surround sound as a consumer format goes back to the 1970’s
although its roots precede that by several decades in cinematic applications,
and even in concert performances such as Pink Floyd’s “Games for May” concert
of 1967. The appeal of surround sound is
quite obvious – why constrain the sonic image to the traditional one of a stage
set out in front of you? Arguably, this
idea was first reduced to practice by Hector Berlioz in his “Grand Messe des Morts” or Requiem, waaaaay back in 1837, which called for
four brass bands to be located in the front, the back, and the two sides of the
performance venue.
In the 1970’s several consumer formats appeared, each aimed
at extending the two-speaker stereo layout with an additional pair of rear
speakers. The term “Quadrophonic” was coined
to describe this arrangement, and there was much enthusiasm in the music
industry to support 4-channel technology with recorded material. As we now know, when new a consumer technology
tries to emerge, the major stakeholders take turns to shoot themselves in the
foot. In this case, the hardware
manufacturers brought forth a plethora of incompatible solutions to deliver a
four-channel experience. QS, SQ, CD-4
(all LP-based formats), 8-track tape, and surprisingly many others, all came
and went. It was another 20 years before
the movie industry, and its DVD technology, finally lit a fire under the
surround sound concept.
One of the problems with surround sound is that it is much
harder to create a solid 3-dimensional sonic image which creates the same
soundfield for multiple listeners distributed throughout the listening
room. This problem is exacerbated for
home theater applications where there is a physical image (the screen), and a
need for much of the sound – particularly the dialogue – to appear to come from
it. This resulted in the adoption of the
front center speaker, through which dialogue can be readily piped. Also, in movie soundtracks the role of deep
bass is dramatically different from that of pure audio, and so a special
channel which provides only deep bass (the “Low
Frequency Effects” channel) was specified.
This complete configuration is well known today as “5.1”. Additional main speakers tend to be added from
time to time, and today’s home theater receivers often support up to “7.1”
channels.
Now that surround-sound's structural formats have at last become
established, the music industry can now focus on recording and delivering music
in multi-channel formats. The venerable
CD is too old to be adapted to surround sound, and so SACD is now the only
viable hardware format available for delivery of multi-channel audio content (its
one-time competitor and supposed vanquisher, DVD-Audio, is all but extinct now). Except that here in the West, as consumers, we
omitted to climb on the SACD bandwagon.
If only Sony and Philips had marketed SACD as a surround-sound format
rather than an audio quality format, things might have turned out differently.
Anyway, audiophiles being audiophiles, the surround sound
debate is alive and well. There is an
emerging body of opinion that says the centre speaker is actually ruinous when
it comes to creating a stable sonic image.
Additionally, sub-woofer advocates believe that a single LFE channel is
inadequate, and that each full-range speaker needs its own sub-woofer. There is also (thankfully) some agreement
that, for classical music at least, the two rear speakers do not need the full
20Hz bass response. What we used to
refer to as “Quadrophonic” is now called 4.0 and one of its keenest advocates
is Peter McGrath, a revered recording engineer whose day job is Sales Director
for Wilson Audio Specialties. Peter’s
classical recordings are absolutely the finest I have ever heard, so his
opinion counts for something! But relatively few multichannel SACDs are presented in 4.0 format.
