home entertainment 2007

oomy woofer. Conversely, you
wouldn’t want to pair a silky-sounding
ribbon tweeter with an overdamped,
lean-sounding woofer.
Per Kristoffersen has effectively
matched the tweeter’s character—pleasingly
airy, somewhat soft and forgiving
yet finely detailed—with the woofers’
by slightly underdamping the latters’
tuning. But that’s not to suggest that
the Diablo’s top is dull or muted, or
that its bass is slow, woolly, or sloppy.
The Diablo was extended and supple
at both frequency extremes, providing
exceptionally natural instrumental textures
that were free of edge, brightness,
or grain on top without sounding dull
or uninvolving, while the low frequencies
were sufficiently well controlled to
sound nimble and firm but never
thumpy. The extension into the low
bass from the two 9" woofers was
deep, full, and satisfying.
When the Diablo was called on to
deliver the low organ-pedal notes in
the second movement of Saint-Saëns’
Symphony 3, from a 1987 LP with
Marek Janowski conducting the
Radio France Philharmonic Orchestra
(Harmonia Mundi HMC 5197),
those notes appeared as very deep,
distant, well-controlled, compacted
thunder—just as they had earlier that
same evening, during a live performance
at Avery Fisher Hall. Never
mind that Avery Fisher doesn’t have
an organ, and that those notes were
generated electronically via a pair of
tractor-trailer–sized subwoofers
placed against the back of the stage.
The pedal notes on the Janowski
recording had authority, weight, and a
velvety texture that avoided sounding
canned or one-notey, or even as if
they were emanating from the speakers.
Low bass may be omnidirectional,
but some speakers that go very low
also produce an audible mechanical
backlash that is directional. The Diablo
didn’t.
The Diablo handled electric and
acoustic bass equally well, convincingly
reproducing both the harder attack
of the former and the softer attack of
the latter. Lovers of hard rock and
orchestral music will be thrilled with
the Diablo’s low-frequency performance
in terms of both extension and
dynamics. With live recordings taped
in large venues, the pair of them easily
produced an illusion of enormous
space. The speakers’ response was subjectively
smooth, and extended down
PEAK CONSULT EL DIABLO
into the 30Hz region in my room. The
Diablo didn’t produce the Wilson
MAXX 2’s slam, but that would not
have meshed with the rest of the speaker’s
sonic personality.
Kristoffersen asks the Diablo’s 5"
midrange driver to handle an unusually
wide bandwidth: 200Hz all the way
up to 4800Hz, or 2kHz higher than in
most two- and three-way designs,
which usually cross over at 2.7kHz or
so. The advantages of extending the
midrange’s bandwidth so high are
tonal and phase continuity in a critical
musical frequency range. For instance,
fundamental violin frequencies range
from just below 200Hz up to just
above 3.1kHz, and a concert grand
piano is capable of fundamentals from
around 28Hz up to almost 4.2kHz.
The overtones, of course, go much
higher, but having a single driver
reproduce the key instrumental funda-
ASSOCIATED EQUIPMENT
ANALOG SOURCES Continuum
Audio Labs Caliburn turntable; Continuum
Cobra, Graham Phantom,
Kuzma Airline tonearms; Lyra Titan i,
Air Tight PC-1, EMT Jubilee JSD 5,
Transfiguration cartridges.
DIGITAL SOURCES Musical Fidelity
kW DM25 DAC & transport, BPTmodified
Alesis Masterlink hard-disk
recorder.
PREAMPLIFICATION Manley Steelhead,
Blue Amp MC 42 phono preamplifiers;
Musical Fidelity kWP,
DartZeel NHB-18NS preamplifiers.
POWER AMPLIFIERS Musical Fidelity
kW monoblocks, Music Reference
RM-200.
LOUDSPEAKERS Wilson Audio Specialties
MAXX Series 2.
CABLES Interconnect: TARA Labs
Zero, Shunyata Research Antares
Helix. Speaker: TARA Labs Omega,
Stereovox LSP-600. AC: Shunyata
Research Anaconda Helix, JPS AC.
ACCESSORIES Continuum Audio
Labs Castellon magnetic isolation
stand, Finite Elemente Pagode
equipment stands, Symposium
Rollerblocks; Audiodharma Cable
Cooker; Shunyata Research V-RAY
Reference, Hydra 8 power conditioners;
Oyaide AC wall jacks; ASC Tube
Traps, RPG BAD & Abffusor panels;
Furutech DeMag’ Loricraft CD and LP
demagnetizer, VPI record-cleaning
machines. —Michael Fremer
mentals, in addition to many of the
resulting harmonics, should result in a
strong sense of musical continuity.
Indeed, I found that just such a continuity
was one of the Diablo’s key
strengths. It gushed forth a sense of
smooth musical flow while suppressing
the discontinuities that afflict some
multi-driver designs.
But in any speaker, piling so much
on the midrange driver’s plate will
result in tradeoffs. One of these is that,
as the frequencies reproduced by the
cone rise, so does its directivity, which
leads to “beaming” at the higher frequencies
within the driver’s bandpass.
As the frequencies rise, the amount of
cone area used to reproduce those frequencies
decreases and becomes concentrated
toward its recessed center,
where it attaches to the voice-coil.
However, rather than being heard as
excessive brightness, the result is usually
an overly polite sound—the driver
can’t produce enough off-axis output at
the higher frequencies to provide adequate
frequency and power response to
fill the room.
Another potential problem created
by extending a relatively large cone’s
response is the nonlinearity caused by
the cone’s flexure. However, the Diablo’s
smoothness leads me to suspect
that AudioTechnology’s expertise has
tackled that problem, just as Peak Consult’s
Per Kristoffersen has successfully
navigated the off-axis response issue.
Which is not to say that Kristofferson’s
choice was inaudible. The Diablo
had a slightly mellow overall sound,
with less sparkle and life than some
might wish, as well as a very slight, easily
ignored coloration that I heard as
just a touch of compression or congestion—what
JA likes to call “hootiness”—
in the upper mids and lower treble. In
fact, this was the first thing I heard
when the Diablos were first fired up in
my room—but, as it has with all great
speakers, my ear/brain system quickly
made peace with this coloration, which
quickly blended into the musical flow
and disappeared. (And if you think your
favorite speaker is without colorations,
think again.)
When I encountered—in an enormous
room—another pair of El Diablos
at the 2007 Consumer Electronics
Show, I immediately heard that same
minor coloration. Yet despite the
venue’s size, which should have exacerbated
the off-axis response problem,
those Diablos sounded remarkably
www.Stereophile.com, May 2007 95