User Manual

CABLE THEORY

Page 8

As with OFHC and OCC, the nomenclature “six nines” or “eight nines” has almost no meaning. All else

being equal, higher purity is a straight forward benet. However, grain structure, softmess and surface

nish can each make more difference than a “nine” or two. Then there is the matter of measurable pu-

rity. Due to contamination caused by the measuring process, there is a serious question as to whether

any metal can be veried as having greater than six nines purity. Also, since “nines” became a selling

point, some quite absurd and dubious claims have been made. Let the ears beware.

Once copper has been processed and rened to the Nth degree, the only improvement left is to go

to a long-grain high-purity silver. AudioQuest FPS (Functionally Perfect Silver) is just such a superior

material. It was expensive, but the results were transparency, delicacy, dynamics and believability that

weren’t possible any other way... until PSC copper. FPS silver is still used to excellent effect in many

CinemaQuest (from AudioQuest) wideband cable.

In the previous several paragraphs a number of important metallurgical concerns have been litsed,

such as purity, grain structure, softness and surface nish. Earlier in the discussion of skin-effect it was

mentioned that the only place with 100% magnetic eld and current density is at the surface of a con-

ductor. This means that the surface purity and smoothness does more to dene the sonic character,

or hopefully lack of character, than any other part of a conductor. This is why AudioQuest’s recently

introduced new range of metals are called “Perfect Surface.”

Perfect Surface Copper (PSC) is drawn and annealed though a novel proprietary integrated process

which creates an exceptionally soft copper conductor with an astonishingly smooth and uncontami-

nated surface. Ever since the beginning, AudioQuest cables have improved over time. Starting in 1987

with FPC copper, a foundation was created by four levels of superb conducting materials. On this foun-

dation, renements such as SST continually provided further discrete improvements. With the introduc-

tion of PSC copper, a whole new foundation has been laid. For a price not much higher than FPC, PSC

offers more natural and accurate performance than even FPS silver. AudioQuest’s CV-4 speaker cable

is identical to Type 4 in every way, except for the use of PSC copper instead of LGC. Coral interconnect

is identical to the previous Ruby and Quartz designs, except for using PSC instead of FPC (Ruby) and

FPC-6 (Quartz).

Importance Of Overall Speaker Cable Geometry

We have been discussing problems within a single conductor, solid or stranded, regardless of polarity

(+ or -). The relationship between conductors is also very important. If this relationship is not consistent,

then the electrical parameters (such as capacitance and inductance) of the cable will be constantly

changing and the signal will be distorted. Conductors can be parallel, spiraled (twisted), or braided.

These various geometries have certain inherent qualities. Parallel construction is inexpensive. Spirals

have good RFI (radio frequency interference) rejection and usually lower inductance. Braids have good

RFI rejection and low inductance, but suffer the consequences of a constantly changing electrical envi-

ronment for each conductor.

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 ltering 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