As a cable designer who possesses a mere AAE in Electricity/Electronics, I have always been inherently dubious about writing a "white paper" or design principles essay regarding Luminous Audio's cable theories. For decades we heard fundamental electrical engineers state that there are no definitive reasons that any audio cables should be "capable" of altering the sound in any way provided they would pass a bandwidth of 20-20k hz (a very easy task btw). After conversing with a recent engineer buddy of mine, Arthur Ball, I realized I had found my man to assist me with such a difficult task. Art is currently working on his PHD in EE although already possessing 3 engineering degrees. It amazed me to discover Art had experienced everything I have believed for the last 22 years and counting. Cables make an unquestionable difference and, although most cannot be scientifically measured, any seasoned audiophile certainly can do so given their system is of adequate resolution for such comparisons. You will find the following essay to be a healthy read but quite worthwhile if you are of the aforementioned stout engineering principle or if you have always wondered; "why can these audible phenomenons not be measured?" I assure you that you will find Art's writings extremely informative.
Tim Stinson-Luminous Audio Technology
I met a fellow engineer John Landry through the purchase of his Cary V12i amplifier and we started chatting about the impact of cables and why they do indeed sound different. Since we are both electrical engineers, I gave him my impressions on the potential technical reasons we can hear differences between cables. Tim Stinson heard about my ramblings and asked me to put together this informal essay about cables and how they affect our stereos. I have been in the home audio hobby for about 10 years.
Having been involved in this hobby at an accelerated pace, I have tried lots of different equipment and combinations thereof to see where the outer limits of the performance envelope lie. I feel this is very important to make informed decisions, as well as knowledgeable ones. I have spent a lot of time comparing my auditory observations with concepts I learn in class, fueled by curiosity. These days, I believe that the basis of our engineering knowledge is generally oversimplified and doesn't correlate with our reality very well. All formulas are ultimately simplifications, all the problems we solve don't cover all the possible variables - the world is more complex than we assume it is. We have models for this and that but in the end, they are simply assumptions collected together to simulate reality. The Taylor Series Expansion from calculus is a describing function for any system that follows physical laws. It is made up of a series of differential "parts" where each one has a different impact on the system at hand and they are placed in order, from the most significant to the least significant. The interesting thing of it is that the series actually goes on forever but we pretend that isn't the case. In engineering, we just take the first couple of parts that are the most important and we throw the rest away, labeling it as "insignificant." However, are they truly insignificant? Is there existence not to be recognized in any way?
This truncation doesn't make itself apparent until you analyze something in extreme detail - like we do with our stereos. Only then is the resolution extensive enough to uncover these subtle high-order effects. And yet, this detail is invisible to the crude mechanical means we have for external analysis today. A microphone doesn't even come close to doing what our ears and brains can do and so we cannot rely solely on objective means for an answer. If we do, we can't see the big picture. In life as in hi-fi, we are always dealing with an infinite number of variables, even when it appears to be otherwise. Experimentation, and only experimentation, takes all the variables into account (i.e., it includes the human listener in the feedback loop), not just the ones we think are the most important, so you can faithfully and unequivocally trust that result. And in my experience, that results says that yes, cables can make a real difference just like better amplifiers and better speakers can. But this still doesn't explain the "why" and that I have no clear answer for that thus far, only speculations I like to think about.
One of my theories is that our ears are extremely sensitive to tonal balance - much more so than we take for granted - and cables can and do change the tonal balance. The majority of our impressions are due to this balance - and deviations thereof. For instance, transparency and detail have to do with the amount of high frequency extension present and a 0.5dB change is clearly audible. An amplifier is modulated by the widely varying speaker impedance and so it adds "waves" in the resulting tonal balance. Depending on where the peaks lie, the sound can be interpreted as slow, veiled or fast. When it comes to cables, why they too change the tonal balance change is not very clear, but I (and some others) think it has to do with 1. Axial traveling waves that get reflected at impedance differentials and, 2. Interface lattice discontinuities that result from cold rolling and die extrusion manufacturing techniques of the wire itself.
Starting #1, we'll take a quick look at both effects. Traveling waves occur all the time in every interconnection and are extensively studied in Power Systems engineering. You get wave reflections at every impedance transition so for a cable example: From your speaker driver assembly to its wire, from the other end of the wire to your crossover and each part thereof, from the crossover to the binding post, from the post to the spade, from the spade to the wire, from the wire to the other spade, from the other spade to the amp post, and so on. This represents tons of waves traveling at all different frequencies with constructive and destructive interference happening all the time. This induces off-kilter time-varying electromagnetic fields - and everyone who owns a cell phone knows that electromagnetic fields can bring havoc on a signal.
The reason we would notice this impact from cables has to do with the electrical potentials in the entire room. The French government is doing research in this field and these are their latest findings. The air we breathe is made up of many ions that have an electrical charge. It is estimated that there are about 50,000 heavy ions per cm2 in a typical house and about half are positive and the other half are negative. These ions crash into the sound pressure waves coming from the speakers, leaving tiny amounts of distortion in the wave front due to their mass. The ions get energy from the collision use their charge to establish an electrical network in the entire air space. This network then "plugs" into the stereo by connecting through the surfaces of cables, drawn by the electric field that the musical signal creates. It is basically the exact same as a phenomenon that has been witnessed in the development and placement of galaxies in our universe, but on a much smaller scale obviously.
Getting back to the electrical side of things, there can be a significant voltage potential between different parts of a stereo and anyone that has been shocked by static electricity, will attest to it. The voltage potentials are on everything and affect everything, despite the fact the effect is infinitesimal and ranks very low on in the Taylor series. The charges are affected by weather, number of people breathing in the room, airflow, furnishings, location of the house, etc. Some cables can be MUCH more prone to their effects than others, boiling down mainly to the type of shielding. It would be easy to dismiss this theory by claiming that the effects couldn't possibly be audible and yet, we know there are changes in sound with different cables and changes also with the weather.
On to #2. At the molecular level, a wire's lattice structures are in total chaos. There are deformations all over the place due to being forced into the shape of a wire by a giant spaghetti press, valence band charges have incorrect polarity or are trapped altogether since the conduction band resistance is, relatively, off the charts. To get an energy balance, these confused charges have to reach the lowest energy level and they do that by getting complimentary charges from the signal flowing through the cable, i.e., our music. I believe this is what the "break-in" phenomenon actually is (yes, I have experienced it many times). I don't doubt the brain induces some of the effect since it gets used to something easily, but triboelectric charges are a reality and they eventually balance out and the cable effectively becomes "neutrally charged" and stops taking charge from the passing signal. From that point on, the cable stays neutral and the sound ceases to change. However, if you take the cable and bend it all around and twist it so that the insulation rubs on the wire, you change the charges quite a bit and the cable needs to be broken in over again.
But then the cable will always retain its capacitance and inductance and will modify the tonal balance according to these values - just like speaker crossovers do but on a small scale. This is what ends up giving a certain cable its "signature" sound. However, the final assessments are almost totally dependant on the human doing the listening. If he or she has poor hearing, a cable that has a flat high frequency response will sound dull, lifeless and boring with compromised dynamics. If that same system is heard by someone with excellent hearing, it could be the best cable he has ever heard in that system. It is all relative and we cannot forget that our ears have their own tonal balance which gets impacted greatly by how we have taken care of our hearing throughout our life, as well as aging in general. And this tonal balance in many cases will have more drastic consequences than the tonal balance shifts due to #1 and #2.
Sincerely, Art Ball
To sum up Art findings and place them in true "Luminous Audio Technology terms," we cannot imagine that a device for measuring micro-dynamics, inner detail, and coherency of audio cables will ever be invented. An experienced audiophile with excellent hearing is truly the only resource we have for discerning such subtle differences. I am proud to say that Luminous Audio will never stop striving to bring its clients closer to the live experience with cables of high resolution and lack of artifacts. "Music so clear you can see it" so-to-speak!
Luminous Audio Technology