ON TRACK
A 5. 1 Surround Sound Primer
This month we’ll jump off the neck a little bit
and talk about some music technology that’s
becoming more and more relevant as we move
towards the big switch to DTV (digital television). When February 17, 2009 rolls along, all
analog broadcasting is scheduled to stop. But
what does DTV have to do with us PG readers,
you may ask? Well, a quick flip through any
cable, satellite or fiber network will reveal an
increasing number of channels broadcasting in
5. 1 surround sound.
format called DTS (Digital Theater Systems).
First appearing in 1993 in the movie Jurassic
Park, it’s an option on many DVDs and Blu-rays, but television networks broadcasting
in surround only do so with Dolby Digital,
not DTS. However, standard DTS retains the
same layout as a 5. 1 Dolby Digital signal (L,
C, R, LS, RS, LFE). There are also formats
such as Dolby EX and DTS ES that have 6. 1
mixes, but just know that 5. 1 Dolby Digital is
the defacto “standard.”
like stereo, but “spread out” into the speakers,
creating a much wider soundfield. Note that
I’ve also had to deliver music cues I’ve composed for trailers or commercials in surround,
so it’s not just limited to shows or concerts.
On my Verizon FIOS network for
example, there are not only concert
channels (such as FUSE HD) that are
produced in surround sound – sports
networks, nature shows, movies and
entertainment programming have all
begun featuring multichannel content. In addition to network shows
(and even commercials), most DVD’s,
Blu-rays and video games are also
delivered with surround audio. So let’s
step behind the scenes and see what
it takes to get started doing surround
sound production.
Plasma or LCD
Screen
Front Speakers
should be set
either side
of the screen
The Center Speaker
can be positioned
above or below
the screen
But how do you record surround? Well, like
most other things, there is no right or wrong
answer. While there are surround microphones
available (such as the Holophone), you can use
traditional mics to capture multichannel sound.
For example, with an acoustic guitarist
in a room, think about miking above
their head or out in front of them. I rely
on a pair of Earthworks omnis to capture the room, then often place them
equally in both the front, left/right and
surround speakers. The sense of space
is truly amazing, especially with a fine
instrument (and player, of course).
The Subwoofer can be
situated at the back
or side of the room
Listening Position
The term “ 5. 1” is a common one that
signifies discrete Left Front, Center,
Right Front, Left Surround, Right
Surround and LFE (Low Frequency
Effects) channels. The “ 5” represents
the five main speakers and the “. 1”
represents the LFE channel, which is
played back by your home theater system’s
subwoofer. The reason it’s “. 1” is because it
only plays back a fraction (the lows) of what a
full range speaker would.
With an electric, you can use a close
mic the cab, but add another mic up
and out in the room. When mixing in
surround, take that room mic and place
it in the rear surround speakers. Drums
and percussion are especially easy to
capture in surround, simply by adding
additional mics “around” the kit and
mixing as such in 5. 1.
Rear Speakers should
be placed behind or to
the side of the viewer
Five audio channels, plus a LFE (low frequency effects) channel,
complete the 5. 1 surround sound setup.
For those who want to create surround mixes,
you will need five speakers and a subwoofer,
as well as an audio system capable of 5. 1 mixing. Most modern DAWs can easily handle
surround sound (Logic, Digital Performer,
Nuendo, Pro Tools HD, etc.). If you’re mixing
on a console, you will need either a surround-capable one or at least six routable Aux outputs. The P&E (Producer & Engineers) wing of
the Recording Academy recommends having
five speakers of the same type. Much information can be found on this and more (such as
mixing suggestions, etc) in their easy-to-read
PDF document:
But you don’t have to use additional
mics to create surround. You can cre-
atively use delays, reverbs and panning to
spread the tracks out in the 5. 1 environment.
Some programs, such as Logic, even include
multichannel, surround ready reverbs and
delays for just such a job.
Dolby Digital, also often referred to as AC- 3,
is the most common delivery method of 5. 1
surround sound to the consumer. Much information about this can be found on their site,
dolby.com. For the millions of consumers who
have home theaters hooked up to their digital
cable boxes, when a show broadcasts in Dolby
Digital, their receiver will clearly indicate so. On
my Onkyo, you can hear it “click” into surround
mode and “Dolby D” (Dolby Digital) appears
on the display. Suddenly, the sound comes out
of all my speakers, making stereo sound as dull
as black and white TV. On many DVDs and Blu-rays, you might have to navigate to the audio
menu to choose the Dolby Digital 5. 1 mix.
The important thing is to think about how you
can deliver an experience that stereo cannot.
By doing some research and practicing, you
can open your ears up to a whole new way of
mixing. While the above information is just a
place to start, it hopefully spurs you on to learn
more about surround sound production. Next
month, we’ll dig a little deeper into this topic,
so stay tuned.
grammy.com/pdfs/recording_academy/pro-
ducers_and_engineers/5_ 1_rec.pdf
You should know that Dolby has a competing
Most of the work I do in surround is mixing for
either 5. 1 HDTV broadcast or concert DVDs/
Blu-rays. The tracks are individually mixed just
Rich Tozzoli
is a producer, engineer and mixer who has worked with
artists ranging from Al DiMeola to David Bowie. A lifelong guitarist, he’s also the author of Pro Tools Surround
Sound Mixing and composes for such networks as
Discovery Channel, Nickelodeon and National Geographic.
