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Can cables
be bad?
Frankly, all cables are, to some extent. Anytime electronic
signal passes from one point to another through any medium
there will be signal loss and the introduction of distortion.
The trick is to minimize the deleterious effects. That’s
where we come in! With nearly three decades of audiophile
experience behind our team, you can expect the “least
bad” connection between your audio and video components.
You will hear and see the difference! Here’s why…
Damage Control
We all like to describe how a good component improves the
performance of our system, a perfectly legitimate comment.
Unfortunately, buried in this statement is often the misunderstanding
that the better component actually improved the signal in
some way. The substitution of a superior component improves
a system only because it causes less damage.
Cables, like all components, should be chosen because they
do the least damage. This "damage" comes in two
basic forms: a relatively benign loss of information, or a
change to the character. A visual analogy might illustrate
this distinction: consider "perfect" as a totally
clear pane of glass. Since no component is perfect, the best
we can strive for would be analogous to a pane of glass with
a light gray tint. Lower quality components would have a darker
gray tint. These various densities of gray tint would represent
various amounts of lost information.
The logic of a good system is very simple:
Every component matters! The electronics, the speakers, the
cables, even every solder joint, all cause damage. Each component
is like one of the dirty panes of glass in this illustration.
Each one blocks a bit of the view. The quality of the final
performance, or the clarity of the view, is the original signal
minus the damage done by all the pieces in-between. Improving
any one of the components will improve the performance. Cleaning
any one of the glass panes will allow a clearer view.
Recognizing that the challenge is to reduce negatives, to prevent
distortion, makes it much easier to understand "unexplainable"
improvements. If the panes of glass are not only dirty, but
also have a red tint, then as each pane is cleaned and the tint
is eliminated, the "view" of the music will improve
as expected. However, the red, and the awareness of the red,
will not be eliminated until the last pane has been de-tinted.
Damage Control
“Normal” high-purity (tough pitch) copper has about
1500 grains in each foot (5000/m). The signal must cross the
junctions between these grains 1500 times in order to travel
through one foot of cable. These grain boundaries cause a particular
type of irritating distortion in audio cables.
The first grade above normal high-purity copper is called Oxygen-Free
High-Conductivity (OFHC) copper. OFHC is cast and drawn in a
way that minimizes the oxygen content in the copper: approximately
40 PPM (parts per million) for OFHC compared to 235 PPM for
normal copper. This drastically reduces the formation of copper
oxides within the copper, substantially reducing the distortion
caused by the grain boundaries. Additional improvement can be
attributed to OFHC copper having longer grains (about 400 per
foot), further reducing distortion. The sound of an OFHC copper
cable is smoother, cleaner, and more dynamic than the same design
made with standard high-purity copper. Not all OFHC is the same.
Since the most important audible attributes are due to the length
of the grains, we use the name Premium-Grade OFC to describe
the very best OFHC.
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Long-Grain
Copper |
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"Normal"
high-purity Copper |
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WireLogic analog video cables and digital
coax cables use silver-plated copper conductors. At high frequencies
(video, RF, digital), almost all current is carried on a conductor’s
surface. The surface material and finish dominates the characteristics
of the conductor. WireLogic’s select Silver-Plated Copper
provides exceptional performance at the surface… where
it counts the most!
Insulation Material Quality
Consistency is the most universally acknowledged variable in
wideband cable construction. Constant impedance over length
is especially crucial at high frequencies. In WireLogic video
and digital coax cables insulation materials are used that have
uniform electrical values but have the mechanical stability
to ensure a fixed and unvarying internal construction. Nitrogen-injected
Hard Cell Foam (HCF) is used in all WireLogic analog video and
digital coax cables. Compared to other foams HCF has a much
more uniform structure (consistency), better dielectric properties
(less propagation delay), and better mechanical stability to
maintain constant impendence.
WireLogic audio cables use a carefully selected Polyvinyl Chloride
insulation. PVC is under-appreciated because it is too “lossy”
to use in wideband cables. However, PVC’s “friendly”
distortion profile makes it very cost effective for audio.
Solid Core Construction
There are many ways in which skin-effect causes more distortion
in a bundle than in a single over-sized strand. Strands are
constantly changing positions over the length of a cable. Some
leave the surface and go inside, others are "rising"
to the surface. Since the current density distribution in a
conductor cannot change, some of the current (particularly at
higher frequencies) must continually jump to a new strand in
order to stay at or near the surface. Unfortunately, the contact
between strands is less than perfect. The point of contact between
strands is actually a simple circuit that has capacitance, inductance,
diode rectification-a whole host of problems. This happens thousands
of times in a cable, and causes most of the hashy and gritty
sound in many audio cables. This distortion mechanism is dynamic,
extremely complex, and because of oxidation will become worse
over time.
Strand interaction is the single greatest source of distortion
in audio and video cables, and one of the easiest to avoid.
As mentioned above, whenever current crosses the poor oxidized
contact between bare strands, the signal will be altered. In
addition, the magnetic fields of the various strands are constantly
interacting, causing confusion (smearing) and causing the contact
pressure between strands to be constantly modulated. WireLogic’s
solid conductors are the complete solution.
Cable Geometry
This is the relationship between conductors, both of similar
polarity, and opposite (+ and -). A cable may have two or more
conductors. The arrangement of these conductors dictates the
magnetic interaction, the capacitance and the inductance of
the cable. Both capacitance and inductance cause predictable
and measurable filtering and progressively more phase shift
at higher frequencies, though neither is a magic key leading
to optimum performance. The effect of capacitance is somewhat
like a cliff, you can go near the edge as long as you don't
go over the edge. In a given application there is a value at
which capacitance becomes a problem. At a lower value, away
from the edge of the cliff, there is not much penalty. On the
other hand, inductance is always a problem-a constantly accumulating
problem. Capacitance and inductance are not the only important
variables in cable design. However, it is productive to create
cables whose capacitance doesn't "go over the cliff"
while also designing for minimum inductance. Too much intimacy
causes overly high capacitance, braids cause magnetic confusion….its
worth getting the geometry right.
Directionality
All audio and digital audio coax cables are directional, from
hardware store electrical cable to the finest pure silver cables.
All WireLogic audio and digital audio coax cables are marked
for direction. With other cables it might be necessary to simply
listen to the cables in one direction and then the other. The
difference will be clear-in the correct direction the music
is more relaxed, pleasant and believable. While cable directionality
is not fully understood, it is clear that the molecular structure
of drawn metal is not symmetrical, providing a physical explanation
for the existence of directionality. |
