27.2.2000
Julkaistu
Dunlavy Audio Labsin luvalla
The following
review is reprinted in its entirety from the review that Anthony H. Cordesman submitted to
Audio just before it closed. It has been given to Dunlavy Audio Labs to reproduce in its
original form and represents the personal views of the author. Anthony Cordesman is now a
senior reviewer for The Absolute Sound.
The Dunlavy Aletha
Speaker:
Classic Dunlavy Sound with Décor and a High WAF
Dr Anthony H. Cordesman
Dunlavy Audio Labs has always made some of
the best speakers around, and certainly speakers with some of the best measurements. No
manufacturer I know of has put more effort into building speakers with excellent flat
frequency response, impulse response and step response. Few have done as well in plumbing
the depths of the deep bass with equal resolution and detail. There has, however, been a
price tag in terms of size. The Dunlavy SC-Vs that I use as some of my reference speakers
could serve as the obelisks in "2001: A Space Odyssey." Their WAF or "wife
acceptance factor" has ranged from "if you must insist" for the smaller
models to damn near zero for top of the line reference speakers like the SC-V and SC-VI.
The Aletha is only 52" (1320mm) tall and
is a hexagonal enclosure whose maximum dimensions are 14" (356mm) wide by x 14"
(356mm) deep. They use 3/4" MDF with hardwood corners and weigh a substantial 105 lb.
(48 kg) each, but this is still comparatively easy to move. They also come in a wide range
of architectural hardwood veneers. Light or Black Oak are standard and Rosewood, Cherry,
or Natural Cherry are optional.
The Aletha is, incidentally, virtually
identical to Dunlavy's Corinthian I in every respect except appearance. The Corinthian I
offers a totally new approach to speaker décor - an enclosure finished as a Greek column
and painted to resemble marble. I would be tempted to refer to such a design as
"Greek light," but the play on words is simply Apolloing, and I haven't got the
nerve.
That excursion aside, the Dunlavy Aletha is a
very nicely styled design that comes in a wide range of finishes and that should fit
neatly into most room decors. Certainly, it got high marks for "décor" from a
random selection of my friends and neighbors. These are people who have been anything but
gracious about the visual impact of most larger speakers I get in for review, and while
none felt the Alethas bordered on the invisible, even the most critical felt they could
live with it.
As for the technical details, the Aletha
sells for $5,995/pair. It uses one 10" woofer (cast basket, high damping rubber
surround, carbon fiber cone); two 6.5" Mid-Bass (cast basket, high damping rubber
surround) and one 1" composite textile dome tweeter. These are not exotic drivers,
but they are very carefully selected and tested.
The crossover is a first order design using
high voltage, metal film capacitors; precision machined wound, heavy gauge, high purity
copper coils; and CAD designed Mil spec fiberglass PC boards utilizing high purity copper
traces. The internal wiring uses individually isolated ultra pure, proprietary copper
cables.
The Aletha has a biwire, biamp capability,
although I should note that John Dunlavy is among the many speaker designers who believe
that biamping is a good recipe for screwing up the sound of a speaker by adding two
colorations where only one is necessary and that most forms of biwiring simply randomly
alter the designer's crossover design and create more problems than solutions. (Another
major speaker manufacturer has told me he repeatedly does blind testing by shunting the
biwired connectors at the speaker, and states that listeners almost invariably prefer
"more copper" without biwiring to biwiring.) This view is controversial,
however, and respected designers like Richard Vandersteen feel that biwiring has serious
benefits. I find the outcome is very amplifier and cable dependent and suggest you
experiment for yourself.
As is the case with all Dunlavy speakers, the
Aletha's specifications are unusually detailed and demanding. The frequency response is 30
Hz to 20 kHz, +/- 1.5 dB and the -3 dB point occurs at 25 Hz (anechoic). Dunlavy claims
that the pulse coherence and impulse response is equal to or better than most
top-of-the-line CD players and Digital Processors (at 10 ft. on-axis); that the radiation
patterns are precisely symmetrical in both horizontal and vertical planes, and that
diffraction is largely eliminated by the use of efficient sound-absorbing material on all
relevant surfaces. It is well worth your time to check out the curves and details on the
Dunlavy Audio web page (http.//www.dunlavyaudio.com). They are quite impressive, and I
have seen how Dunlavy does its measurements. They can be relied upon.
The Aletha's efficiency is approximately 90
dB SPL (ref: 1 meter, on-axis) for an input level of 2.83 Volts RMS, and the impedance is
a nominal 4 ohms, with a minimum of 3 ohms and a maximum of 6.5 ohms. This makes the
Aletha a good match for any good amp with 50 watts or more per channel and relatively
insensitive to speaker cable characteristics (with the exception of some of the more
eccentric high end designs.)
It is the sound that counts, however, and the
surprising fact is that the Aletha sounds better in some ways than my reference SC-Vs. At
least in my listening room, the SC-V imposes a sonic price for its technical accuracy.
Producing a flat anechoic response means that it has more upper octave energy and less
mid-range warmth than many competing speakers. This results in a sound character that has
a great deal of detail, and some of the best imaging and depth around. At the same time,
it tends to sound a bit bright with many of today's close-miked recordings - which have
more upper octave energy than live music and recordings with more natural miking and
recording.
The overall timbre and frequency response of
the Aletha may measure the same as that of the SC-Vs, but is subjectively warmer than the
SC-Vs. The end result is that it has more of a mid hall sound character than the front of
the hall sound character of past Dunlavys. It is more forgiving of close miking of strings
and soprano voice sounds sweeter. Its timbre is more "musical" with run of the
mill CDs in terms of the upper bass and lower midrange., and particularly realistic with
Cello and the lower wood winds. Male voice is excellent.
At the same time, the level of transparency
and detail is still exceptional. Space the Althea's more widely than most speakers, angle
them so that they almost face the listening position but do not beam directly at the
listener, and you get excellent resolving power. The imaging is terrific - as detailed as
the source permits, with stable, clear images in terms of both width and depth, but no
exaggeration or "etching" of the imaging in unnatural ways. Sound stage depth
and width is equally good, and so is the ability to reproduce the low level sound stage
noises that add realism to live recordings. There is an "electrostatic"-like
coherence to the sound of the Aletha without the coloration of some electrostatics that
makes them sound best at one volume level and less transparent at others.
Dynamics and transitions are very good. The
Dunlavy Aletha does not change sound character at either very low or very high listening
levels. It did very well with moderate power amps, but it was perfectly capable of getting
all of the benefits of the vast power reserves of my Pass X600 amplifiers. Sudden changes
in musical volume take place with exceptional realism, and full orchestral climaxes or
power rock occur without any blurring or sense of effort. At the same time, the softest
piano and violin passages are equally realistic. The Aletha does very well with virtually
any form of voice, but it is particularly good with complex choral passages.
Understand, the kind of sound qualities that
I am praising the Aletha for are musically natural, rather than "audiophile" in
character. There is nothing particularly striking about the sound of the Aletha until you
compare it to the sound of a live performance and realize that its resolving power is most
striking because it is so natural. You do not hear any special character to the sound that
isn't on the recording, or details you would not expect to hear in a good recording that
you do not hear in live music. In short, be careful about dismissing the sound of the
Aletha because your first impression is that it lacks "character." It may not
have much "eccentric charm," but any prolonged listening to really demanding
recordings will convince you that its overall sound character, and particularly its
midrange, is exceptional. The Aletha has character where it counts - in reproducing the
kind of natural musical detail in a way you really want to live with on a long haul basis.
The Dunlavy Aletha also lives up to Dunlavy
Audio Labs' claims that it provides most of the deep bass that Dunlavy is famous for in a
much smaller package. John Dunlavy has previously felt that great bass response required a
large, sealed enclosure, and that alternative designs that use ports, vents or other
devices to reduce enclosure size result in higher levels of distortion and unnatural bass.
He has designed the Aletha, however, so that it matches a 10" woofer (cast basket,
high damping rubber surround, carbon fiber cone) with the acoustical properties of a
well-damped, sealed enclosure. He has also increased its SPL by nearly 3 dB at low bass
frequencies by taking advantage of the "mirror-imaging" enhancements available
with a downward firing woofer radiating through a circular slot aperture just above the
floor level.
While downward firing woofers have been used
before with great success by firms like VMPS, John Dunlavy still feels that the Aletha is
"the first loudspeaker to make full and effective use of this design." Dunlavy
Labs also claims that the hexagonal shape of the Aletha yields virtually diffraction free
performance, with an optimally wide, symmetrical radiation pattern in both vertical and
horizontal planes above approximately 80 Hz. Below this frequency, the radiation becomes
essentially omni-directional, which fills the listening room with bass energy that can be
felt as well as heard.
The end result is that Aletha's deep bass is
not quite as stunning as that of the SC-V, but it is damn good even in a one on one
comparison. The Aletha can produce massive amounts of bass to frequencies well below 30
Hz, and into the region where you feel more bass than you hear. Its ultra low bass is very
good to excellent, and is extremely clean up to the loudest listenable levels on my bass
spectaculars. It did very well with a range of different recordings of the Saint Saen's
Third Symphony. This music is an excellent test of bass, orchestral dynamics, and a
speaker's ability to resolve complex detail. The symphony's climax can easily become a
blurred, acoustic mess with many speakers.
The Aletha does equally well in reproducing
the incredible deep bass organ on Jean Gillou's performance of Mussorgsky's Pictures at an
Exhibition (Dorian-90117) and in reproducing more natural, non-spectacular organ
recordings. It had outstanding transient performance on percussion, even with bass drum
spectaculars like the opening passages of "Fanfare for the Common Man," on
"Copland, The Music of America" (Telarc CD-80339). It had minimal coloration on
bands one and eight of Jennifer Warnes' "The Hunter" (Private Music
01005-82089-2), and this is performance that is rare in speakers in its price range.
Equally important, it did an exceptional job
of reproducing the mid and upper bass and lower midrange. This gave it unusually good
sound stage detail and ambiance, and overall dynamics. It provided some of the most
natural reproduction I have yet heard on Ray Brown's bass viol trio on Super Bass (Telarc
CD-83393).
Naturally, you do have to give something up
for a smaller enclosure and fewer drivers. The Aletha goes low, but it can't move as much
air at subterranean levels as the SC-V, or play as loudly. At the same time, the Aletha
proved to be far less room sensitive and was much easier to place in a real world living
room without creating standing waves than the SC-Vs. My SC-Vs present a problem in my
listening room (but not in many others). They excite more standing wave boundaries than
smaller speakers with less bass response. This not only makes them difficult to place in
the room, it creates a fairly narrow listening area in which I do not hear the boundary
effects in the bass.
In summary, the Dunlavy Aletha presents one
of the best mixes of sound characteristics available in its price range and does so in an
enclosure that fits comfortably into a real-world life style. It may not have all of the
deep bass extension, power handling capability, or technical accuracy of the larger
Dunlavy reference monitors, but it is cheaper and is a far more practical speaker for
normal listening rooms. For many audiophiles it will also be more musical. The Aletha is
the kind of investment that can give you pleasure for years and it is well worth a
listening session if you are in the market for a reference quality monitor that you can
truly live with!
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