Serblin's work to date has been indisputably musically rewarding,
and executed with unmistakable Italian brio, its foundations are
firmly fixed in traditional high-fidelity concepts and engineering.
By contrast, the Guarneri owes more to fine materials, centuries-old
craftsmanship, and the vital contribution that the structure of
a musical instrument plays in its sound. The Guarneri Homage is
a limited-edition, virtually made-to-order speaker. Only a few
craftsmen are capable of building its enclosure, and then only
in limited quantities—no more than 10 pairs per month.
A typical design strategy
for a new loudspeaker consists of a program of technical research
into various acoustic options, which are then tailored and tuned
to produce a good-sounding product. With the Guarneri, however,
the music came first. I can do no better than to quote Sonus
Faber: "High technology has a way of blurring and obscuring
the ideal solutions that precede us, in the belief that only
the latest solutions can possibly be the best."
To justify the use of the
name Guarneri, Serblin started from the view that this loudspeaker
had to be a music-making instrument. This can be a mixed blessing:
it may result in a radically different design, but there may
also be some fatal, unforeseen flaw in the overall performance.
For example, if an engineer consciously or unconsciously limits
the design's frequency range and/or maximum available loudness,
then magically satisfying results can be obtained in the all-important
midrange. Sounds restricted to that range may be reproduced
with unprecedented vibrancy. But if such a speaker is incapable
of satisfactorily reproducing the climax of a symphony, or fails
to do justice to even a moderately loud drum or the sparkle
of a chime, then it will ultimately be found wanting.
However, Serblin's putting the music first, coupled with the
novel and acoustically optimal cabinetry, has resulted in a
speaker that's not only superbly musical, but also Sonus Faber's
most accurate to date. As an acoustic engineer, I find that
particularly rewarding (footnote 3).
Whether just sitting there
or playing music, the Guarneri is never boring—it's fundamentally
true to the spirit of the music it plays.
The Guarneri is loosely based on the "larger-than-life"
Sonus Faber Minima Amator (reviewed in December 1993, Vol.16
No.12, p.174), which costs a fraction of the Guarneri's price.
As the Guarneri's every detail has been fine-tuned, it's worth
exploring in greater depth how the speaker is built. Again,
quoting Sonus Faber:
"The [cabinet] comprises
42 separate elements hand-sawn from solid wood. Each element
is bonded to its neighbor using organic glue and heat pressing
techniques identical to those used centuries ago in the manufacture
"The walnut, maple,
and limewood used for the various parts is dried naturally for
two years and then stabilized in kilns. The rear of the enclosure
is shaped from a single block of limewood. The interior walls
of the enclosure are selectively damped using proprietary sheet
copper and lead tuning elements."
To which I would add that
the 1"-thick driver baffle, covered in grained black leather,
consists of 15 layers of birch multi-ply. An aluminium-alloy
extrusion forms the inner section of the sculpted rear deck
and carries the bass-reflex loading duct and the terminal array.
The main curved body of
the enclosure is said to be partly voiced by the specific technique
of layered finishing, in the manner of a violin body: "The
surface of the wood is prepared for finish by first sealing
it with albumin to prevent penetration of the multilayered varnish.
The application of many coats of varnish is the time-honored
tradition in violin-making that has a profound effect on the
final sound. We assure you that the sound of 'Guarneri Homage'
benefits from the special finish produced by blending natural
organic substances, including Venetian larch turpentine, linseed
oil, propolis, wine alcohol, gamboge, copal gum, and oliban.
No fewer than ten coats of varnish are applied to each cabinet,
hand-sanding then accompanying each finishing coat."
After the final polishing,
which is done by hand, each Guarneri cabinet is buffed to a
mirror-like finish. The finish is certainly deeper and clearer
than speakers that have polyurethane or cellulose-based piano-gloss
With few exceptions, cabinet
resonances are major influences on the a speaker's sound quality;
it's well-known that even a speaker's finish affects its sound.
"Special Edition" loudspeakers can thus prove surprising:
Even a multi-coat, synthetic-lacquer finish can improve the
sound, as in the case of the Monitor Audio Studio series. The
original Wilson Puppy woofer enclosure had a very tough plastic-laminate
finish that appreciably reinforces the cabinet. Even with inexpensive
speakers, the use of real-wood veneers can result in sound different
from that with wood-print, vinyl-film finishes.
The Guarneri's side enclosures
are between ?" and 1" thick, and the internal mass
loading comprises nine lead-weighted copper strips of different
lengths, disposed in a staggered formation to fine-tune and
distribute the resonances. This technique is also applied to
the top panel. Both top and bottom are made from solid, 1"-thick
walnut. Internal damping is confined to one piece of acoustic
foam in the lower rear section. The idea is that the speaker's
irregular shape helps dissipate standing-wave energy, while
the minimizing of acoustic damping helps retain a "free"
The knuckle-rap test invoked
an interesting result: The 10-liter (internal volume) enclosure
is certainly solid, but the panels lacked the familiar knock-on-woodblock
sound. The decay signature was more subtle and harmonious, reflecting
the enclosure's complex structure and form.
As befits a musical instrument, no specifications are provided
for this loudspeaker—fascinating, if a tad frustrating
for the reviewer. Sonus Faber intends that their dealers be
accorded total responsibility for designing a complementary
audio system that will bring out the Guarneri's promised performance
in the owner's home. How this is achieved is not necessarily
the purchaser's concern.
The review samples were loaned to me by Ricardo Franassovici
of Absolute Sounds of London, who gently suggested that perhaps
lab tests would be inappropriate in a "concept" speaker
such as this. I see his point: It should be the sound that counts,
aside from any prejudices imparted by an interpretation of lab
test figures. (Reviewers know only too well that both the design
of test methods and the interpretation of their results are
subjective.) On the other hand, a well-designed test program
can reveal not only flaws (if present), but can also help to
define a product's performance envelope, and hence make it easier
to obtain that product's best performance. Such information
is valuable, even if it does remove some of the mystery of the
It's fairly easy to estimate
some of the Guarneri's basic parameters: Its bass response will
extend to a modest 45Hz or so, along with a probable power handling
of 100W peak program, a nominal 6 ohm impedance, an average
sensitivity of 87dB/W (rather higher than an LS3/5a or a Celestion
SL700, for example), and a maximum in-room sound level of perhaps
102dBA. This is a good level for the peaks on classical music,
but not really sufficient for disco or rock. Deep bass will
be absent, but, as the Minima Amator demonstrated, this doesn't
mean the speaker will be incapable of producing a well-balanced,
The Guarneri's bass driver,
custom-made for Sonus Faber by Scan-Tech, employs a larger-than-usual
voice-coil 54mm (2") in diameter. This is energized by
a huge magnet with a deep, 14mm top plate. The light, polypropylene
diaphragm has a decorative milled surface, and is suspended
on a half-roll surround of natural rubber, with minimal loss
at low frequencies. The diecast woofer frame is nominally 165mm
(6.5") in diameter, and the rear port, ca 1.6" in
diameter by 4" long, tunes the system to 52Hz.
The tweeter, also custom-built,
is a version of Dynaudio's Esotar unit and features a 28mm surface-damped
soft dome made of silk. The unit is fitted with a special, large,
rear chamber carved from solid walnut. The two drive-units are
vertically aligned on the contoured, low-diffraction front baffle,
the tweeter on the top.
The hard-wired crossover
networks are mounted on a solid MDF tray. All the components
are dipped in resin for mechanical stabilization. Selected multistrand
OFC wire is used. The filters are nominally 6dB/octave over
the crossover range, augmented by additional components to shape
the acoustic output. The treble high-pass section thus has three
elements: two film capacitors and an air-core shunt inductor.
For the woofer's low-pass section, the primary element is a
large series air-core inductor with an RC Zobel network and
an additional film capacitor. The multi-way binding posts allow
for normal and bi-wiring, or even bi-amping.
The grille is based on two
enameled castings that push-fit on stainless-steel bars mated
with the enclosure. Strung like the strings of a guitar between
the grille sections is a vertical array of closely spaced, woven
The Guarneris are supplied
with a pair of very tall, well-proportioned pillars (see below).
These stands are no less than 39" high, placing the intended
listening axis a little below the bass/mid unit. The main column
of each pedestal is disguised by a full-height array of threads
similar to those in the grille, again strung between precision
castings. With the speakers sitting on the stands, the system
is heavy but stable; spikes are unnecessary, though the enthusiast
might try shallow cones under the massive travertine base. These
speakers thrive on free space, and don't need a nearby wall
to achieve their optimum bass performance—finicky setup
is not required.
The Guarneris sounded pretty good straight out of the box (footnote
4), but it was obvious from the first audition that they would
continue to reveal additional layers of performance subtlety,
mandating lengthy experimentation. Power amplifiers used included
Meridian 605 monoblocks and the Naim NAP 250, augmented by the
new Krell KSA-100S and KSA-200S. The Musical Fidelity A-1000
class-A amplifier, although out of the Guarneri's price class,
showed that these speakers need an amp that is sweet and harmonically
Because the Guarneri has
good bass (within its natural limits) and rhythm, the power
amplifier must be competent in these areas. My less-than-comprehensive
list includes the Jadis Defy-7, the Acoustic Research VT130
(with BL-1 unbalanced-to-balanced converter, as required), and
the Conrad-Johnson Premier series. From my electronics I expect
an easy, subjective transparency; a good sense of air and delicacy;
natural stereo perspectives; and, above all, harmonic neutrality.
Conrad-Johnson Premier Twelve monoblocks offer all these things.
The Premier Eleven can also produce civilized results, provided
you don't require flat-out maximum loudness.
On the front end, I found
a passive line-level controller (Audio Synthesis Passion Vishay)
to have the least editorial effect on the system (my cable runs
were suited to passive drive). On the preamp side, the zero-feedback
Conrad-Johnson PF-2 (review forthcoming), with its MC stage,
was a fine starting point. I also still favor the base-line
Audio Research LS3 for its uncomplicated vitality. Toward the
end of the evaluation period, I borrowed a Conrad-Johnson PV10
and found it to be a very good match—particularly with
the Premier Eleven.
I used the Lingo'd Linn
LP12 with the Koetsu Rosewood 2 phono cartridge mounted in a
Naim ARO unipivot tonearm. The Guarneri featured classic audiophile
sound on black discs, yet also conveyed the good rhythm and
timing of which the Linn combo is capable—most entertaining.
Digital sources included the PS Audio Reference Link/Lambda
combination connected directly to the Audio Research VT 130
in balanced mode, and in unbalanced mode to the other amplifiers
listed earlier. The Audio Synthesis DAX decoder also sounded
very good in this system.
Cables mattered. I found
that van den Hul The First and Second carbon-fiber cables worked
best. Bi-wiring the speakers maximized clarity and transparency.
Heavy-duty speaker cables were unnecessary; I tried van den
Hul Revelation with very good results, but they fit awkwardly
to the terminals. Lighter-grade silver cables, such as Siltech
and Kimber, were effective.
Once everything was in place, the Guarneri really sang. Forget
mainstream hi-fi; forget head-banging levels; forget gut-wrenching
bass; forget the garage-door slam! Instead, remember the purity,
unmistakable sense of liveness, scale, and sense of presence
of real sounds in the listening space—this is what the
Guarneri is all about.
In these abilities, the
speaker that comes closest to the Guarneri is the Quad ESL-63.
I admire the Guarneri's ability to conjure up a Quad-like, electrostatic
sound from a pair of moving-coil drivers, even if they're encased
in a truly remarkable wooden enclosure. I could easily say,
"If you appreciate the broad midrange fidelity of the Quad,
but wish for a sensitive, beautifully crafted miniature on a
tall, elegant pillar, then look no further than the Guarneri."
It's rare to find a speaker
that's truly balanced—with a tonal, harmonic linearity
that extends from the upper bass to the high treble. In this
respect, the Guarneri eclipses the other Sonus Faber designs.
The bigger models, particularly the Electa Amator and Extrema,
will play louder, are more dynamic, and have better, deeper
bass; but rarely is a speaker as truthful to its source as the
In a typical room setting—ideally
one with a ceiling higher than 10'—the Guarneris disappeared
acoustically, leaving a remarkably high, wide, and deep soundstage
that had state-of-the-art focus. The speaker's tonal quality
spoke of chamber music played in an 18th-century paneled room
with polished wood floors and a few carpets, the walls hung
with oil paintings and a few medieval tapestries.
Astonishingly, that character
did not obscure musical detail or atmosphere. In fact, the Guarneris
were very transparent, with high resolution and recovery of
low-level detail and ambience. Definition was lost only when
the speaker was worked hard in the bass, and the reflex port
added some mild distortion.
More than anything else,
the Guarneri's neutrality and low levels of coloration, born
of an accurate frequency response and overall frequency balance,
defined the speaker's exceptional, wholly believable performance.
The sound of the Guarneri was beautifully proportioned—like
its appearance. There was no deep bass, but because the speaker's
sound was otherwise so complete, I didn't notice the loss.
The Guarneri's inner balance
and smoothness were so good that the speaker proved unusually
tolerant of a wide range of program qualities and matching ancillaries,
cables, and amplification. They handled natural acoustic sounds
best; this means that, to some degree, the speaker might be
less impressive on heavy rock or strongly synthesized sounds.
Nevertheless, although the Guarneris were more believable on
orchestral music, they still rocked better than any true miniature
I know of.
Transients were excellent.
Subtle sounds, such as the brushstrokes on drums and cymbals,
and Airto Moreira's natural percussion repertoire (Killer Bees,
B&W Music 041), were rendered with the startling accuracy
of a good electrostatic. Vocals were articulate, unforced, and
harmonically correct. This speaker could have been designed
to reproduce only Vivaldi, so well did it capture the atmosphere
of a string performance. And though the Guarneri is small, like
its Sonus Faber brethren, it didn't show it. Without any false
brightness, this speaker provided an upbeat, involving tempo,
showing good timing on tight jazz combos.
Subtle and fine-grained,
the Guarneri did not need a "power" amplifier, in
the accepted sense of the word. Rather, it derived its finest
performance from a harmonic match to a sweet, pure amplifier—preferably
tubed—in the 50-100W range. (Solid-state amplifiers are
by no means ruled out, but the Guarneri neither needs nor benefits
from such major powerhouses as the Krell KSA-200S or -300S.)
With such a combination, I found I could listen to digital sources
for longer periods without fatigue.
The Guarneri also played
quite loud, its good sensitivity making the most of my amplifier.
Once I adjusted to its sense of natural scale and superb perspectives,
I found this system wholly satisfying. Time and again, the reproduction
had that ring of truth—the richness and rasp of orchestral
brass, the singing quality and "edge" of violin, and
the attack and pitch of xylophone and woodblock. On Steve Reich's
Music for Mallet Instruments (Elektra 7559-79220-2), the Guarneri
revealed the complex interplay of musical strands while preserving
the overall structure and almost relentless flow of the compositions.
One aspect did prove worthy
of experiment. In my room, the exceptional height (39")
of the pillar stand placed the woofer's acoustic center close
to halfway between the floor and the 110" ceiling. Such
a position maximally excites the half-wave floor-ceiling mode,
which in this case lies at 60Hz. The high odd-order modes—at
180Hz, etc.—are also excited by placing the speaker on
such a high stand, endowing the speaker's lower midrange with
a characteristic "boxiness."
If the Guarneri is custom-ordered,
the customer can request moderately different pillar heights.
I didn't have any other Faber pillars, so I used 31" Stone
stands. These worked just fine, moderating the mild room-mode
coloration. A slight uptilt corrected for the change in vertical
axis—this and the degree of toe-in can be used to fine-tune
the tonal balance for a particular room acoustic. I liked the
Guarneris best with my ear level with the midrange/woofers (see
If the Guarneri is not used
with appropriate ancillary components, it becomes simply good
hi-fi. But if set up properly—taking account of its unique
qualities—the Guarneri breathes music.
The Sonus Faber Guarneri Homage may be a small speaker, but
it sure portrays music with style and class. How can you dispassionately
place a value on its superb, fine-furniture-quality enclosure,
the visual unity between the speaker and its pedestal, and the
spirit and labor that have gone into the creation of this remarkable
Technically, the Guarneri
is a very well-balanced, elegant design with a useful sensitivity,
allied to a kind amplifier-load characteristic. Coloration was
low, response uniformity very good, distortion moderate, and
it was very easy on the ears. It doesn't have extended bass,
but the bass it does produce is sufficiently weighty, articulate,
and tuneful. However, this description doesn't do justice to
the sheer quality of sound produced by this highly refined instrument.
When the Guarneri is driven
by good tube electronics, you can forget about the mechanics
of hi-fi and let the music take precedence. Though it may not
be suitable for headbangers or technofreaks, the Sonus Faber
Guarneri is a classic whose purchase you'd be unlikely to regret.
Franco Serblin has upheld the worthy goal of honoring the great
tradition of Guarneri stringed instruments.
Sidebar 1: Specifications
Limited-edition, two-way loudspeaker with matching stand. Drive-units:
1.1" (28mm) silk-dome tweeter, 6.5" (165mm) polypropylene-cone
woofer. Manufacturer's specifications: None. Measured specifications:
crossover frequency: 2.5kHz. Electrical crossover slopes: 1st-order,
6dB/octave. Frequency response: 55Hz-20kHz, ±3dB. Sensitivity:
86.5dB/W/m (2.83V). Nominal impedance: 6 ohms. Power handling:
100W peak program.
Dimensions: 15" (381mm) H by 7.5"
(190mm) W by 14.75" (375mm) D. Approximate internal volume:
Price: starting at $9000/pair. Approximate
number of dealers: 1.
Manufacturer: Sonus Faber, Via L. da Vinci
63, Arcugnano (VI), Italy. Tel: (39) 0444-962699. Fax: (39)
0444-962687. Distributor: Sumiko, 3101 Telegraph Avenue, Berkeley,
CA 94705. Tel: (510) 843-4500. Fax: (510) 843-7120. Web: www.sumikoaudio.com.