T
he biggest problem with surround-sound systems is that they
require wires to drive the surround channels. And if you don’t want
to drill holes in your walls, floors, or ceilings, you’ll have to try to hide
the wires along baseboards and under rugs (both to prevent a tripping
hazard and to avoid destroying your room’s décor). Even the so-called
wireless surround-sound systems aren’t truly wireless—most have
power cords to drive their amps and radio receivers (and the ones
we’ve reviewed have hissed like cornered tomcats).
After listening to a train of virtual surround-sound systems thatcouldn’t come close to duplicating a true 5.1-channel speaker sys-
tem, we’d pretty much dismissed the notion of producing surround
sound using a single speaker enclosure. But after publishing a White
Paper on digital audio projection (DAP) in October 2005, and then
one on head-related transfer functions (HRTFs) in January 2006, we
decided to give technology another chance. We chose Cambridge
SoundWorks’ $1,000 SurroundWorks 200 Virtual Home Theater
System to represent HRTF technology and pitted it against Yamaha’s
$900 YSP-800 digital audio projector.Head-Related Transfer Functions vs.
Digital Audio Projection
DIGITAL AUDIO PROJECTOR:
Yamaha YSP-800, $900,
http://www.yamaha.comhead 2 head TWO TECHNOLOGIES ENTER, ONE TECHNOLOGY LEAVES
SEX APPEAL
The YSP-800 DAP arouses instant techno-lust, sport-
ing 21 (that’s twenty-one ) 1.62-inch drivers inside its all-steel enclo-
sure, plus two 3.94-inch midranges. Each of the smaller drivers is
powered by a discrete 2-watt amplifier, and each mid is paired with a
20-watt amp. DSP algorithms create five distinct sound beams that
reflect off the room’s walls and ceiling, tricking your brain into believing
that the sounds are originating all around you.
HRTFs are basically filters that use psychoacoustic tricks to
position virtual sound sources around your head. Because they
don’t require large speaker arrays, these systems don’t look as
sexy as DAP components. The SurroundWorks 200 consists of
three 2.78-inch full-range drivers, supplemented by a subwoofer.
An amp supplies 50 watts to each satellite and 75 watts to a 6.5-
inch sub. WINNER: DAPround^1
MUSIC
The vast majority of music that most of us listen to is
recorded in conventional stereo, so it’s crucial that a surround-sound
system provide excellent channel separation without leaving a big
hole in the middle. Both systems proved adept at creating satisfyingly
broad, yet well-defined soundstages with generous sweet spots.
We were equally content with both technologies when it came to sur-
round-sound music recordings. Both the HRTF and the DAP systems
made us feel as though we were right onstage in the midst of the
performers. It is vital, however, that the Yamaha system be mated
with a carefully chosen powered subwoofer—the system by itself has
no bottom-end to speak of. (We tested it with a Boston Acoustics PV-
800.) WINNER: TIEround^2
BY MICHAEL BROWN16 MA XIMUMPC APRIL 2006
VIRTUAL SURROUND SOUND SPEAKERS: