Top Six Reasons Audiophiles Hate The Center Channel

Do
audiophiles hate the center channel? It may sound like a strange notion, but I
have encountered this phenomenon time and again over the last 20 years. I first
moved to Los Angeles from my home state of North Carolina in 2002. I worked
downtown at the LA Times, and the commute was brutal — over an hour in stagnant
freeway gridlock if I went straight home at 6pm. Sometimes, instead of driving
south to head home, I’d leave the office and take the quick trip north to
Hollywood, where I’d kill time doing something fun until traffic died down.
More often than not, you’d find me near Sunset and Vine. My favorite movie
theater was there, the Arclight Hollywood, home to the famous Cinerama Dome.
Not only did the Arclight deliver excellent picture and sound quality, it also
had a beautiful lobby (decorated with actual props and costumes from big
movies), a full-service restaurant frequented by celebrities, a really cool
gift shop, and — crucially — the best popcorn and cleanest bathrooms of any
movie theater I’ve ever been to. Right next door to the theater was my favorite
record store, Amoeba Music. Like me, it was new to LA. Bigger than a Tower
Records or Virgin Megastore, it still managed to embody the cool vibe and
independent spirit of a smaller neighborhood record shop. Amoeba was incredibly
well stocked with a huge variety of music, movies, and collectible merchandise.
And it was there, in 2003, that I bought the newly-released DVD-Audio version
of one of my all-time favorite albums, Pet Sounds by the Beach Boys. I
had only been into multi-channel music for a year or two at that point, having
collected just a handful of SACD and DVD-A discs. The Pet Sounds DVD-Audio included new stereo and 5.1-channel
mixes by producer Mark Linett.
I liked the high-res stereo mix, but the surround mix was… weird.

Some
instruments that are clearly audible in the mono and stereo mixes were somehow
lost, buried deep in the multichannel mix. Lead vocals were often placed both
in the rear channels and up front, resulting in a soundstage that didn’t make
sense. In some cases, lead vocals were missing from the front right channel,
even though they played at full volume from the rear speakers. There was very
little low bass, and the subwoofer’s LFE channel didn’t seem to be engaged at
all, despite the fact that the album features superb Fender bass parts played
by the legendary Carol Kaye. But perhaps the most noticeable of the many
curious mix decisions made for this multi-channel release was the complete lack
of content in the center channel. It simply wasn’t used at all. Concerned that
there was a problem with my playback system, I consulted the liner notes and discovered
that Linett made a point of
omitting the center channel, preferring instead to create a “wide approach to
the music” by relying on a phantom center. Granted, a phantom center can work
remarkably well, as anyone who has ever heard a properly-set-up stereo system
can attest. But you can’t expect to create a phantom center for the lead vocals
if you pan them all the way to the left, leaving the front right channel to
twiddle its thumbs. There’s also an argument to be made that the point of a
good multichannel mix is to take advantage of the potential sonic experiences
that only such a setup can produce. As recording and mixing engineer John Traunwieser pointed out in our livestream about Dolby Atmos home theater, some surround mixes are aggressive
(or “wacky,” as he put it) in their use of the surround channels, while others
are more subdued. Both approaches can be compelling. But one thing that all
good mixes share is a well-anchored, generously proportioned front soundstage,
able to recreate the spaciousness and/or specificity present on the recording.
Obviously, a center channel can play a key role in building a front soundstage
capable of accomplishing this goal.

Center Channel Mixing Practices for Spatial Audio Music

The
next time I was at Amoeba, I made my way to the back room where the SACD and
DVD-A discs were kept, along with other “audiophile” music. I saw the guy who
had sold me the new Pet Sounds release and told him about the bizarre
mix, and how producer Mark Linett
had said in the liner notes that the use of the center channel was “simply not
needed.” I expected the Amoeba employee to be on my side, but his response
surprised me. Now, it has been two decades, so I don’t remember his exact
words. But he said something along the lines of, “Makes sense to me.
Audiophiles hate the center channel.” At the time, this response was startling
to me. But in the intervening years, I have encountered many audio enthusiasts
whose opinions seem to support the claim.

So Why DO Some Audiophiles and Music Mixers Hate the Center Channel?

In
an effort to explain the anti-center-channel sentiments of some audiophiles,
Chief Audioholic Gene DellaSala recently made a video discussing this
surprisingly controversial topic, in which he lays it out, plain and simple.
Here are the top six reasons why some audiophiles hate the center channel.

1.
They chose the wrong center channel.

There
are many different designs used for center-channel speakers, and generally
speaking, some are better than others. Gene discusses some of the most common
horizontally oriented center-channel speakers, including basic MTM (mid/woofer,
tweeter, mid/woofer), nested MTM (in which the tweeter is slightly raised so
all three drivers can be closer together), and W(T/M)W. The latter is a 3-way
design in which a vertical tweeter/midrange stack is centered between two
woofers. Lastly Gene touches upon a TWWT design. Avoid those like the plague.

See: Pros and Cons of Various Center Channel Designs

The basic and nested MTM
designs can sometimes work well, as we’ve seen from loudspeaker manufacturers
like Arendal Sound and Focal. But if you get more than, say, 15-20 degrees off
axis (that is, you’re sitting off to the side, not directly in front of the
speaker), you’re going to experience lobing effects — there will be nulls in
the frequency response. This usually occurs in the critical midband, where the
two midrange drivers are sharing frequencies. The result? Dialogue
intelligibility can suffer dramatically. You end up cranking the volume, and
you’re still not satisfied. 

If you’re setting up a home theater with multiple
rows and a wide left-to-right span of seats, you’re better off with a W(T/M)W
design, such as the Monitor Audio Silver C250 7G, or the massive $18K Focal
Viva Utopia Center Loudspeaker. These are three-way designs with dedicated midrange
drivers, so if you’re running three-way towers for your main left and right
speakers, you’ll get better matching with a W(T/M)W center channel. And you
won’t experience any lobing problems, so you’ll get clearer dialogue across all
of your seats. 

A slight variation of this design would be a three-way speaker
in which the tweeter is concentrically mounted inside the midrange driver.
We’ve seen a number of these designs from KEF, Elac, Tannoy, and others.
Paradigm’s Founder 90C ($2899 each) is also a good example. In general, these
speakers tend to offer the same benefits as W(T/M)W designs. On the opposite
side of the performance spectrum you’ll find some older center speakers with a
TWWT design. These speakers cause all sorts of sonic problems, but thankfully,
they are very rare these days. 

Editorial Note about Identical LCRs: One
final thought about choosing a center-channel speaker. If you really want the
sound of your center-channel speaker to match up for seamless transitions with
your main speakers, you can always go with an identical model for all three
channels. Some home theater enthusiasts even use identical speakers for all
channels, but that isn’t always practical. It’s usually easy enough to get your
front stage to match, however. Look for brands, such as Perlisten and Arendal,
that offer center speakers nearly identical to their monitor speakers. Other
brands, such as KEF, Focal, and Paradigm, offer speakers marketed as LCR
designs, meaning the same speaker can be used for Left, Center, and Right
channel duty.

2.
Improper center
channel placement.

Behind the 150″ AT Severtson Screen lies the RBH Sound SI-831/R to match up with Gene’s SVTRS Tower Speakers

This
one is fairly simple. Even if you have the right speaker, it won’t sound right
if you don’t position the speaker correctly. Gene has often run into theaters
in which the owner has a good center speaker, but has it placed far too high or
far too low — even sitting directly on the floor. The center speaker should be
positioned in line with the main speakers, and as close to the display as
possible. Placing the speaker too high or too low will prevent seamless pans
across the front stage, and will result in loss of detail and intelligibility
since you’re effectively sitting off axis from the speaker. Another placement
mistake to avoid is putting the center speaker inside of an entertainment
center, bookshelf, or credenza. This isn’t always easy to avoid, but placing a
speaker inside a piece of furniture will change its acoustical properties. When
a speaker is placed in a cavity made of highly reflective surfaces, that
environment will have major effects on the sound of the speaker, all before the
sound even enters the room. If you do need to place the speaker inside a
cabinet or other cavity, try stuffing the cavity with foam and placing the
speaker at the very front edge of the shelf or opening in order to prevent
diffraction from the surface.

3.
Bad calibration (time alignment).

Even
if you have your speakers level-matched (that is, they’re putting out equal
SPLs as measured from the listening position), your system won’t sound right if
you don’t have delays set to properly time-align the speakers. This is
especially important when upmixing two-channel music, because information from
the Left and Right channels is being copied and sometimes rerouted to the center-channel speaker. If
you don’t have the time alignment right, you can cause all sorts of combing
issues (comb filtering occurs when certain frequencies are either
amplified or attenuated by the superposition of a delayed version of the
original audio signal onto itself). Also, the focus of the image can actually
shift, and you won’t get the detailed center-channel information. Speech
intelligibility will “go out the window,” as Gene puts it. One easy way to get time
alignment right is to use a receiver or processor with a good auto-calibration
system, such as Audyssey MultEQ-X Pro,  Dirac Live
or Anthem
ARC Genesis.
Or, you can do it yourself using a laser ruler to get accurate distance
measurements between the main listening position and the tweeter of each
speaker.

4.
Wrong upmixer settings for 2CH music.

This
can be a big one. If you got an early Dolby Atmos receiver and tried using
Dolby Surround Upmixer to upmix two-channel music, there’s a good chance you
were disappointed. Without the “Center Spread” feature enabled, you likely
heard a narrow front stage in which all of the sound was crowded around the
center speaker, and the imaging from the main speakers was completely lost.
This kind of upmixing works OK if you’re watching a stereo video and you want
the dialogue pushed to the center speaker, but for music, it’s frankly
terrible. Older solutions, like Dolby Pro Logic IIx, had separate Music and
Cinema modes, providing a better experience. If you’re listening to music with
Dolby Surround Upmixer, make sure that Center Spread is turned on. This will
restore the imaging of your main speakers, but with an enhanced center fill.
Gene doesn’t recommend using DTS Neural:X for
upmixing two-channel music because there’s no adjustability in the center
channel. Again, it works well for upmixing a two-channel movie or TV show, and
it also works well for upmixing a 5.1-channel audio track into a more immersive
format, since 5.1-channel mixes already have a discrete center channel (Pet
Sounds notwithstanding). Auro-3D upmixing can also cause center-channel
problems if the room size settings aren’t correct, so proceed with
caution. Auro 3D properly set up can give excellent results for 2CH music upmixing. Auro 3D upmixing seemingly places more emphasis to the front soundstage, which Gene says he often prefers when listening to Jazz music, as opposed to the more spacious envelop of sound the DSU offers.

5.
Bad tuning between Mains and Center (Room EQ, Acoustically Transparent screen
loss compensation).

While
auto-calibration systems are typically good at setting levels and time
alignments, they aren’t always great at dialing in the EQ settings so that your
center speaker sounds the same as your main Left and Right speakers. In many
cases, the user just goes with the auto-calibration,
not realizing that the system made errors. Or perhaps you have your center
channel behind an acoustically transparent screen, as Gene does in the
Audioholics Smart Home theater. Despite the name, acoustically transparent
screens do have an effect on sound. It is possible to compensate for this
effect in EQ during the system tuning process, but if you don’t, even three
identical speakers may not sound the same from the listening position.
Depending on the screen you’re using, you might need to raise the treble up
3-6dB to compensate for the high-frequency attenuation caused by the screen
material. Fabric screens will cause less of a problem than vinyl screens.

6.
Some audiophiles are just 2-channel purists.

There’s
not much to be done about this last reason — some audiophiles are simply stereo
purists, and to them, a center-channel speaker will always be an abomination in
the context of a music-only system. These are the folks that the Amoeba
employee was referring to when he said that audiophiles hate the center
channel. They just want to enjoy the magic that is stereo imaging. We all know
how great a good stereo recording can sound on a good two-channel system, and
there’s nothing wrong with knowing what you like! So if you’re just into
stereo, you can rest easy in the knowledge that nobody is going to break into
your house and install a center-channel speaker. That said, a properly set-up
multichannel system can deliver its own kind of magic, whether for music or for
home theater. And unlike the phantom center provided by a two-channel system, a
center-channel speaker allows your front soundstage to sound stable and
anchored in place even when you’re sitting well outside the traditional stereo
“sweet spot.” If you avoid the pitfalls described above, using a center-channel
speaker in your multichannel system can allow you to enjoy a seamless,
immersive audio experience that might just convert the stereo purist in your
life. Are you an old-school stereo purist, or do you embrace the center
channel? 

Share your thoughts in the related forum thread below.