I am a fan of Chris Sommovigo's Black Cat and Airwave interconnects. I hope he does not mind me quoting him or naming him on this subject, but Chris does not mark directionality of his IC's. I recently wrote him on the subject and he responded that absent shunting off to ground/dialectric designs, the idea of wire directionality is a complete myth. Same with resistors and fuses. My hunch is that 95% of IC "manufacturers", particularly the one man operations of under $500 IC's mark directionality because they think it lends the appearance of technical sophistication and legitimacy. But even among the "big boys", the myth gets thrown around like so much accepted common knowledge. Thoughts? Someone care to educate me on how a simple IC or PC or speaker cable or fuse without a special shunting scheme can possibly have directionality? It was this comment by Stephen Mejias (then of Audioquest and in the context of Herb Reichert's review of the AQ Niagra 1000) that prompts my question;
Thank you for the excellent question. AudioQuest provided an NRG-10 AC cable for the evaluation. Like all AudioQuest cables, our AC cables use solid conductors that are carefully controlled for low-noise directionality. We see this as a benefit for all applications -- one that becomes especially important when discussing our Niagara units. Because our AC cables use conductors that have been properly controlled for low-noise directionality, they complement the Niagara System’s patented Ground-Noise Dissipation Technology. Other AC cables would work, but may or may not allow the Niagara to reach its full potential. If you'd like more information on our use of directionality to minimize the harmful effects of high-frequency noise, please visit http://www.audioquest.com/directionality-its-all-about-noise/ or the Niagara 1000's owner's manual (available on our website).
@jea48 Thanks for posting that. Stupidly, I've always tried to type the quote after clicking on the "quote" icon and it only worked a few times. I could never get back to regular font. Copy and Paste seems quite normal to most but to a dinosaur like me....
@jea48 Thanks for posting that. Stupidly, I’ve always tried to type the quote after clicking on the "quote" icon and it only worked a few times. I could never get back to regular font. Copy and Paste seems quite normal to most but to a dinosaur like me....
All the best, Nonoise
I had trouble getting the thing to work using the old internet explorer. Sometimes I could get it to work while other times it would not. Then sometimes the damn thing would not leave a space below the grey vertical line for me to post a message. With Mozilla Firefox It seems to work fine. Though sometimes I have to click on it again to get it, the grey vertical line, to show in the message box. Practice makes perfect.
We’ll see if geoffkait takes the time to get it to work for him. You can lead a horse to water, .......
Something that has not been mentioned, I do not believe, is the dielectric insulator used to cover the IC and speaker cable wires. The type of insulation covering over the wire may influence cable direction. Especially if the cables were broken-in in one direction and then reversed for what ever reason and hooked back up in the opposite direction. Or maybe one was replaced in the same direction but the other one was reversed.
I would hope we all agree new ICs and speaker cables go through a break-in period.
Coaxial cable
Coaxial cable Poynting vector in a coaxial cable, shown in red.
For example, the Poynting vector within the dielectricinsulator of a coaxial cable is nearly parallel to the wire axis (assuming no fields outside the cable and a wavelength longer than the diameter of the cable, including DC). Electrical energy delivered to the load is flowing entirely through the dielectric between the conductors. Very little energy flows in the conductors themselves, since the electric field strength is nearly zero. The energy flowing in the conductors flows radially into the conductors and accounts for energy lost to resistive heating of the conductor. No energy flows outside the cable, either, since there the magnetic fields of inner and outer conductors cancel to zero.
Electrical energy delivered to the load is flowing entirely through the dielectric between the conductors. Very little energy flows in the conductors themselves, since the electric field strength is nearly zero.
There are many factors that make cable break-in necessary and many
reasons why the results vary. If you measure a new cable with a
voltmeter you will see a standing voltage because good dielectrics make
poor conductors. They hold a charge much like a rubbed cat’s fur on a
dry day. It takes a while for this charge to equalize in the cable.
Better cables often take longer to break-in. The best "air dielectric"
techniques, such as PFA tube construction, have large non-conductive
surfaces to hold charge, much like the cat on a dry day.
Cables that do not have time to settle, such as musical instrument and
microphone cables, often use conductive dielectrics like rubber or
carbonized cotton to get around the problem. This dramatically reduces
microphonics and settling time, but the other dielectric characteristics
of these insulators are poor and they do not qualify sonically for
high-end cables. Developing non-destructive techniques for reducing and
equalizing the charge in excellent dielectric is a challenge in high end
cables.
The high input impedance necessary in audio equipment makes uneven
dielectric charge a factor. One reason settling time takes so long is we
are linking the charge with mechanical stress/strain relationships. The
physical make up of a cable is changed slightly by the charge and visa
versa. It is like electrically charging the cat. The physical make up of
the cat is changed by the charge. It is "frizzed" and the charge makes
it's hair stand on end. "PFA Cats", cables and their dielectric, take longer to loose this charge and reach physical homeostasis.
The better the dielectric's insulation, the longer it takes to settle. A
charge can come from simply moving the cable (Piezoelectric effect and
simple friction), high voltage testing during manufacture, etc. Cable
that has a standing charge is measurably more microphonic and an uneven
distribution of the charge causes something akin to structural return
loss in a rising impedance system. When I took steps to eliminate these
problems, break-in time was reduced and the cable sounded generally
better. I know Bill Low at Audioquest has also taken steps to minimize this problem.
Mechanical stress is the root of a lot of the break-in phenomenon and it
is not just a factor with cables. As a rule, companies set up audition
rooms at high end audio shows a couple of days ahead of time to let them
break in. The first day the sound is usually bad and it is very
stressful. The last day sounds great. Mechanical stress in speaker
cables, speaker cabinets,
even the walls of the room, must be relaxed in order for the system to
sound its best. This is the same phenomenon we experience in musical
instruments. They sound much better after they have been played. Many
musicians leave their instruments in front of a stereo that is playing
to get them to warm up. This is very effective with a new guitar. Pianos
are a stress and strain nightmare. Any change, even in temperature or
humidity, will degrade their sound. A precisely tuned stereo system is
similar.
You never really get all the way there, you sort of keep halving the
distance to zero. Some charge is always retained. It is generally in the
MV range in a well settled cable. Triboelectric noise in a cable is a
function of stress and retained charge, which a good cable will release
with both time and use. How much time and use is dependent on the design
of the cable, materials used, treatment of the conductors during
manufacture, etc.
There are many small tricks and ways of dealing with the problem. Years
ago, I began using PFA tube "air dielectric" construction and the charge
on the surface of the tubes became a real issue. I developed a fluid that adds a very slight conductivity to the surface
of the dielectric. Treated cables actually have a better measured
dissipation factor and the sound of the cables improved substantially.
It had been observed in mid eighties that many cables could be improved
by wiping them with a anti-static cloth. Getting something to stick to
PFA was the real challenge. We now use an anti-static fluid in all our
cables and anti-static additives in the final jacketing material. This
attention to charge has reduced break-in time and in general made the
cable sound substantially better. This is due to the reduction of
overall charge in the cable and the equalization of the distributed
charge on the surface of conductor jacket.
It seems there are many infinitesimal factors that add up. Overtime you
find one leads down a path to another. In short, if a dielectric surface
in a cable has a high or uneven charge which dissipates with time or
use, triboelectric and other noise in the cable will also reduce with
time and use. This is the essence of break-in
A note
of caution. Moving a cable will, to some degree, traumatize it. The
amount of disturbance is relative to the materials used, the cable's
design and the amount of disturbance. Keeping a very low level signal in
the cable at all times helps. At a show, where time is short, you never
turn the system off. I also believe the use of degaussing sweeps, such
as on the Cardas Frequency Sweep and Burn-In Record (side 1, cut 2a)
helps.
A small amount of energy is retained in the stored mechanical stress of
the cable. As the cable relaxes, a certain amount of the charge is
released, like in an electroscope. This is the electromechanical
connection.
Many factors relating to a cable's break-in are found in the sonic
character or signature of a cable. If we look closely at dielectrics we
find a similar situation. The dielectric actually changes slightly as it
charges and its dissipation factor is linked to its hardness. In part
these changes are evidenced in the standing charge of the cable. A new
cable, out of the bag, will have a standing charge when uncoiled. It can
have as much as several hundred millivolts. If the cable is left at
rest it will soon drop to under one hundred, but it will takes days of
use in the system to fall to the teens and it never quite reaches zero.
These standing charges appear particularly significant in low level
interconnects to preamps with high impedance inputs.
The interaction of mechanical and electrical stress/strain variables in a
cable are integral with the break-in, as well as the resonance of the
cable. Many of the variables are lumped into a general category called
triboelectric noise. Noise is generated in a cable as a function of the
variations between the components of the cable. If a cable is flexed,
moved, charged, or changed in any way, it will be a while before it is
relaxed again. The symmetry of the cable's construction is a big factor
here. Very careful design and execution by the manufacturer helps a lot.
Very straight forward designs can be greatly improved with the careful
choice of materials and symmetrical construction. Audioquest has built a large and successful high-end cable company around these principals.
The basic rules for the interaction of mechanical and electrical
stress/strain variables holds true, regardless of scale or medium.
Cables, cats, pianos and rooms all need to relax in order to be at their
best. Constant attention to physical and environmental conditions,
frequent use and the degaussing of a system help it achieve and maintain
a relaxed state. Insights - Cable Break-in
You must have a verified phone number and physical address in order to post in the Audiogon Forums. Please return to Audiogon.com and complete this step. If you have any questions please contact Support.
