WILSON AUDIO Sophia Series 2 User manual

Sophia Series 2 Owner’s Manual

SOPHIA SERIES 2OWNER’SMANUAL
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Wilson Audio® is a registered trademark of Wilson Audio Specialties, Inc.
Cub®, Sophia®, WATT/Puppy®, MAXX®, Alexandria®, and X-1/Grand SLAMM® are
registered trademarks of Wilson Audio Specialties, Inc.
WATCH Center™, WATCH Surround™, and WATCH Dog™ are trademarks of
Wilson Audio Specialties, Inc.
This manual was produced by the Wilson Audio Engineering Department in coop-
eration with Sales and Marketing. The information contained herein is subject to
change without notice. Current Revision 2.0. If you are in need of a more recent
manual, please contact your dealer.
The information in this manual is the sole property of Wilson Audio Specialties,
Inc. Any reproduction, in whole or in part, without the express written permission
of Wilson Audio Specialties, Inc., is prohibited. No material contained herein may
be transmitted in any form or by any means, electronic or mechanical, for any pur-
pose, without the express written permission of Wilson Audio Specialties, Inc.

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Table of Contents
Section 1 - Introduction ..................................................9
New Tweeter ............................................................9
Revised Crossover....................................................10
Recessed Diffraction Pad and Alexandria-Style Pin Grill 11
Section 2.0 - In Your Room ............................................15
Slap Echo ..............................................................15
Standing Waves ......................................................17
Comb Filter Effect ....................................................18
Section 2.1 - Resonance ................................................20
Structural Resonance................................................20
Air Volume Resonance ..............................................21
Section 3.0 - Final Listening Room Setup (Voicing) ........25
Room Shapes ..........................................................25
Zone of Neutrality ....................................................28
Speaker Placement vs. Listening Position ....................29
Speaker Orientation ..................................................30
Summary ................................................................31
Section 4.0 - Preparation ..............................................35
Uncrating Sophia......................................................35
Section 4.1 - Crate Content Checklist ............................36
Section 4.2 - Wiring Attachments ..................................37
Section 4.3 - Sophia Spikes............................................38
Assembly ................................................................38
Section 5.0 - Care of the Finish......................................43
Removing Protective Film ..........................................43

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Dusting the Sophia ..................................................44
Section 5.1 - Care of the Grilles ....................................44
Section 5.2 - Break-in Period ........................................45
Section 5.3 - Enclosure Technology ................................46
Adhesive ................................................................46
Depth of Design ......................................................47
Section 6 - Troubleshooting ..........................................51
Section 7.0 - Sophia Specifications ................................57
Specifications ..........................................................57
Dimensions..............................................................57
Section 8 - Warranty Information....................................63
Limited Warranty ......................................................63
Remedy ..................................................................64
Warranty Limited to Original Purchaser........................65
Demonstration Equipment..........................................65
Miscellaneous ..........................................................66

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Table of Contents

Introduction

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SECTION 1-INTRODUCTION
Section 1 - Introduction
Since its initial release, Sophia has changed the way many think of high-end
loudspeakers. Wilson proved that qualities we once thought contradictory – high
resolution with musicality; prodigious bass in a compact, floor standing package;
dynamic alacrity with an easy to drive load; extraordinary musical experience with
inexpensive electronics – could be married in one, elegant package. In its short
history, Sophia has become a true classic, beloved for musical beauty.
It is no small thing to improve upon something so special as Sophia. The
risk is that some elusive ingredient key to her magic would give way in the process
of pushing another area of performance. The design team knew that in developing
Alexandria X-2, MAXX Series 2, and the new Duette they had uncovered new tech-
nologies that, if applied to Sophia, would improve her performance. So, with a
protective eye on preserving those qualities that imbued Sophia with intrinsic
grandeur, Wilson Audio set out to improve on Sophia’s strengths through an appli-
cation of these new technologies.
Wilson Audio introduces the Sophia Series 2.
New Tweeter
There is some confusion in the market place as to what technical qualities
are important to musically correct high-frequency performance. While other man-
ufacturers blindly pursue dubious performance parameters such as ultra-wide
bandwidth or gratuitously exotic materials, Wilson continues to focus on those

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technologies that truly contribute to better performance. The MAXX Series 2 fea-
tured new proprietary tweeter technology that significantly reduced spurious noise
artifacts generated in the rear of the tweeter. The result was high frequencies with
unprecedented transparency and resolution combined with a much lower noise
floor. This same technology has been applied to the new Sophia Series 2 tweeter.
Sweet, delicate highs were already a hallmark of Sophia. The Series 2 tweeter
builds on these strengths with greater air, sweetness, resolution, and an utterly
grainless sense of purity. Highs emerge from a silent, black background.
Revised Crossover
David Wilson and the Wilson engineering team are ever searching for the
sources of time-domain distortion. During the development of Alexandria, Wilson
discovered that the interaction between the high and low pass filters created prop-
agation delay noise they dubbed “crossover jitter.” Dave and the engineers created
crossover strategies and topologies that reduced this deleterious interaction. The
reduction in distortion-noise allowed Dave and the design team to hear into the
loudspeaker, detect and parse out problems previously obscured by the noise.
Thus the breakthrough not only improved the areas of performance directly related
to the anti-jitter technology, but also allowed enhancements to be made in other
areas of the loudspeaker as well. This process was applied during the development
of MAXX Series 2, and now has been employed in the Sophia Series 2. In the
Sophia Series 2, low-level details, previously obscured by noise, now shine forth
from a black background. Midrange beauty, clarity, and musicality, already a

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SECTION 1- INTRODUCTION
strong point of Sophia, are noticeably better in the Series 2. Instrument texture
and timbre are more convincingly rendered and complete.
Recessed Diffraction Pad and Alexandria-Style Pin Grill
Introduced in the Alexandria and subsequently employed in the MAXX
Series 2, the austenitic stainless steel pin system ensures non-resonant and reliable
grill attachment. The diffraction pad, which previously sat atop Sophia’s baffle, is
now recessed flush to the façade. Problems of diffraction pad detachment are
nearly eliminated. Sophia’s shape is enhanced, taking on a more finely sculpted
and integrated profile.
In designing the original Sophia, Wilson Audio determined to introduce not
merely a more accessible loudspeaker, but the best compact single cabinet loud-
speaker we could build, and the best loudspeaker in its price range, period. To
improve upon that was a daunting task. Wilson Audio’s engineering team accom-
plished its goal and, with Sophia Series 2, has again raised the bar in terms of per-
formance, value, and sheer beauty.

Section 2 - In Your Room

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SECTION 2-INYOUR ROOM
Note: The following section contains general information on room acoustics
and loudspeaker/room interaction. The concepts outlined below are equally
relevant when dealing with multi-channel audio or home theater. The careful
application of these concepts, as you evaluate the acoustical characteristics of
your own room configuration, will allow you to optimize the performance of
your Sophias.
Section 2.0 - In Your Room
There are three commonly encountered room reflection problems, slap
echo, standing waves, and comb filter effects.
Slap Echo
Probably the most obnoxious form of reflection is called “slap echo.” In slap
echo, primarily mid-range and high frequency sounds reflect off of two parallel
hard surfaces. The sound literally bounces back and forth until it is finally dissi-
pated over time. You can test for slap echo in any room by clapping your hands
sharply in the middle of the room and listening for the characteristic sound of the
echo in the mid-range. Slap echo destroys the sound quality of a playback system
primarily in two ways:
• Adding harshness to the upper mid-range and treble through energy
time storage.
• Destroying the delicate phase relationships which help to establish
sound stage and image localization clues.
Nonparallel walls do not support slap echo, but rather allow the sound to

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diffuse.
Slap echo is a common acoustical problem in the typical domestic listening
room because most of these rooms have walls of a hard, reflective nature, usually
being only occasionally interrupted by curtains or furniture. Slap echo can be con-
trolled entirely by the application of absorptive materials to hard surfaces, such as:
• Illbruck Sonex®
• Airduct board
• Cork panels
• Large ceiling to floor drapes
• Carpeting to wall surfaces
In many domestic listening environments, heavy, stuffed furnishings are
the primary structural control to slap echo. Unfortunately, their effectiveness is
not predictable. Diffusers are sometimes also used to very good subjective effect,
particularly in quite large rooms. Sound absorbent materials, such as described
above, will alter the tonal characteristic of the room by making it sound “deader,”
much heavier in bass tonal balance, less “bright and alive,” and “quieter.” These
changes usually make the room more pleasant for conversation, but sometimes ren-
der it too dull in the high frequencies to be musically involving. Diffusers, on the
other hand, tend to not change the high frequency tonal balance characteristic of
the room. Used properly, they can increase transparency. Used incorrectly, how-

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SECTION 2-INYOUR ROOM
ever, diffusers can rob the system of bass richness and add significant midrange
colorations. A combination of absorptive and diffusive treatments is usually the
best approach.
Standing Waves
Another type of reflection phenomenon is standing waves. Standing waves
cause the unnatural boosting of certain frequencies, typically in the bass, at certain
discreet locations in the room. A room generating severe standing waves will tend
to make a loudspeaker sound one way when placed in one location and entirely dif-
ferent when placed in another. The effects of standing waves on a loudspeaker’s
performance are primarily as follows:
• Tonal balance- bass too heavy
• Low-level detail- masked by long reverberation time LF standing
waves
• Sound staging- LF component of image shifted
Standing waves are more difficult to correct than slap echo because they
tend to occur at lower frequencies, whose wave lengths are long enough to be inef-
fectively controlled by absorbent materials such as Illbruck Sonex®. Moving speak-
ers about slightly in the room is, for most people, their only control over standing
waves. Sometimes a change of placement as little as one inch can dramatically
alter the tonal balance of a system because of standing wave problems.
Fortunately, minor low frequency standing waves are sometimes well controlled by

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positioning ASC Tube Traps™ in the corners of the room. Very serious low fre-
quency accentuation usually requires a custom-designed bass trap system.
Low frequency standing waves can be particularly troublesome in rooms
constructed of concrete or brick. This rigid and massive construction method
traps the bass in the room unless it is allowed to leak out of the room through
large window and door areas.
In general, placement of the speaker in a corner will excite the maximal
number of standing waves in a room, and is to be avoided for most direct radiator,
full range loudspeaker systems. Some benefit is achieved by placing the stereo pair
of loudspeakers very slightly asymmetrically in the listening room so that the
standing waves caused by the distance between one speaker and its adjacent walls
and floors are not the same as the standing wave frequencies excited by the dimen-
sions in the other channel.
Comb Filter Effect
A special type of standing wave, noticeable primarily in the midrange and
lower high frequencies, is the so-called “comb filter effect.”
Acoustical comb filtering occurs when sound from a single source, such as a
loudspeaker, is directed toward a microphone or listener at a distance. The first
sound to reach the microphone will be the direct sound, followed by delayed
reflected sound. At certain frequencies cancellation occurs because the reflected
sound lags in phase relative to the direct sound. This cancellation is most apparent

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SECTION 2-INYOUR ROOM
where the two are 180 degrees out of phase. There is augmentation at other fre-
quencies where the direct and the reflected sounds arrive in phase. Because it is a
function of wave length, the comb filter effect will notch out portions of the audio
spectrum at regular spaced intervals.
The subjective effect of comb filter effects, (such as is shown in Figure 1), is
as follows:
• Added roughness to the sound
• Reduction of harmonic richness
• Smearing of lateral sound stage image focus and placement
FIGURE 1-COMB FILTER EFFECT

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Comb filter effects are often caused by side wall reflections. They are best
controlled by very careful speaker placement and by the judicious placement of
Illbruck Sonex® or air duct panels applied to that part of the wall where the reflec-
tion occurs.
Section 2.1 - Resonance
Resonance in listening rooms are generally caused by two sources:
• The structures within the listening room
• The volume of the air itself in the listening room
Structural Resonance
Structural resonances are familiar to most people as buzzes and rattles, but
this type of resonance usually only occurs at extremely high volume levels and is
usually masked by the music. In many wood frame rooms, the most common type
of structural resonance problem is “booming” of walls and floors. You can test for
these very easily by tapping the wall with the heel of your hand or stomping on the
floor. If it is a wooden floor, this is done to detect the primary spectral center of
the resonance. To give you an idea of what the perfect wall would sound like,
imagine rapping your hand against the side of a mountain. Structural wall reso-
nances generally occur in the low to mid-bass frequencies and add tonal balance
fullness to any system played in that room. They, too, are more prominent at loud-
er levels, but their contribution to the sound of the speaker is more progressive.