Detailed technical information for your reference Noise   |   Design   |   Networks   |   Technology   |   Tech Talk   |   Home Cable Construction and Audio Cable Performance Flat cables with parallel members typically have the highest propagation speeds and the widest bandwidth with some of them passing signals freely into the gigahertz region. Coaxial cables are also relatively high propagation speed, wide bandwidth designs. Flat and coaxial cables are the designs of choice for digital and radio frequency transmission. When these extremely wide band cables are used for audio applications, however, they are particularly subject to noise infiltration along the entire length of the cable, much like an antenna.   Flat and coaxial cables ... are particularly subject to noise infiltration along the entire length of the cable, much like an antenna.   The standard ways to approach noise infiltration are through shielding and twisted pair technology, both of which limit cable bandwidth to an extent. Good shielding will reduce electrostatic (ES) noise infiltration. A twisted + and - pair will theoretically prevent electromagnetic (EM) noise infiltration by nulling out these noise frequencies. Cables that employ these geometries will still pass signals freely into the 100 megahertz region and beyond, however, which is far more bandwidth than what is required for audio applications. In reality, however, twisted pair technology only goes part of the way toward canceling out EM noise because the proximity of the twisted + and - pair is never identical over the whole length of the cable regardless of how carefully the cable is manufactured. To reduce EM noise beyond what can be achieved through twisted pair technology requires a properly designed network fitted to the specific application and the length and type of cable. Transparent interconnects are well shielded and both speaker cables and interconnects have twisted pair technology. Our networks clean up any residual EM noise not addressed by twisted pair technology by reducing the bandwidth of the cable to that which is required for the application. Limiting bandwidth to that which is required for the application is a basic audio engineering principle that is adopted in every other component category -- speakers, amplifiers, CD players, phono cartridges, etc.   Limiting bandwidth to that which is required for the application is a basic audio engineering principle that is adopted in every other component category -- speakers, amplifiers, CD players, phono cartridges, etc.   Noise infiltration obscures the ability of the cable to transfer extremely low level harmonic and spatial information accurately, and it has a tendency to make the system sound brighter and harsher in the high frequency region than what is recorded on the source material. Increased noise floor directly affects our ability to perceive full dynamic range and all its gradations. The Role of Inductance and Capacitance in Audio Cables Inductance and capacitance need to be carefully controlled in cable. Too much or too little of either characteristic will provide undesirable results. Flat cables, coaxial cables, and even twisted pair cables without networks exhibit electrical characteristics that are not in the best interest of music for several reasons. In lengths suitable for most home audio systems, these cables have too much bandwidth for audio applications and are particularly subject to noise infiltration. Another problem is the point at which these cables achieve electrical resonance; i.e., the point at which inductive reactance equals capacitive reactance.   Cables with extremely wide bandwidth create a thinner and brighter sound than cables with less bandwidth.   We have tested a wide variety of flat cables, coaxial cables, and twisted pair, nonnetwork designs on high speed gain phase, impedance analyzers in our laboratory. When we fit the analyzer with a typical audio source impedance to drive such cables into a typical audio load impedance, the point at which these cables achieve resonance falls somewhere between 1500-2500 Hz (depending on the specific cable and its length). This means that such a cable becomes more capacitive at frequencies below 1500-2500 Hz, thereby resisting the transfer of frequencies below 1500-2500 Hz. Twisted pair cables typically have a lower resonant point (usually in the 1500-2000 Hz range) than flat or coaxial designs. It takes a $ 70,000 piece of equipment, the engineering wherewithal to set up the test properly, and 3-4 hours of "crunch" time per cable to get the data necessary to correlate our conclusions about a particular cable's resonant behavior under audio load conditions. During our 14 years as a cable company, we have listened to and tested hundreds of different types of cables. Cables with extremely wide bandwidth create a thinner and brighter sound than cables with less bandwidth. We think this condition is primarily caused by too high a resonance.   Customers, recording professionals, and many fellow manufacturers gravitate to Transparent Cables because they are more able to reveal all the fullness, richness, and dynamic quality of the music as it is recorded.   A serendipitous effect of limiting the bandwidth of Transparent Cable with a properly designed network is a lowering of the resonant point, or that frequency where the cable becomes more capacitive and starts to resist low frequencies. In our experience, the sonic byproduct of lowering the resonant point is that music fundamentals and lower order harmonics seem to be passed in the correct proportion to each other and their higher order harmonics. The musical balance is correctly weighted around the two octaves surrounding middle C. Customers, recording professionals, and many fellow manufacturers gravitate to Transparent Cables because they are more able to reveal all the fullness, richness, and dynamic quality of the music as it is recorded. The Role of Group Delay in Cable Design The propagation speed of frequencies will be delayed to one degree or another in any cable. The critical concept regarding propagation speed in cables designed for audio applications is that all frequencies should be delayed the same amount of time (uniform group delay). This means that if different frequencies enter the cable at the same time, they should leave the cable at the same time. Many cables without networks and well designed cables with networks have excellent uniform group delay characteristics.   The extremely fast propagation speeds touted by some manufacturers of extremely wide band cables are really not any measure of musical satisfaction.   Wide bandwidth and extremely fast propagation speeds usually go hand in hand. The inductance of cables with less bandwidth usually is sufficient to reduce overall propagation speed, but if the cables are designed properly, the delay in these cables should be uniform over the usable bandwidth of the cable. The extremely fast propagation speeds touted by some manufacturers of extremely wide band cables are really not any measure of the musical satisfaction users will derive from inserting such cables in their audio systems because of their higher resonant points and susceptibility to noise infiltration. These conditions result in sonic byproducts that are not in the best interest of retrieving all possible musical information from records, CDs, and tapes. The energy balance of audio signals transferred on cables that have higher resonant points and susceptibility to noise infiltration is shifted above the octaves surrounding middle C. The hyperarticulated effects of this energy balance get the listener's attention initially. This hyperarticulated balance has become a hi fi standard in itself, particularly among those hi fi enthusiasts whose focus is on the equipment itself and the various effects that can be achieved by inserting different pieces of equipment in an audio system. Over time, however, this type of sound does not wear well in the ears, minds, and hearts of those looking for a more musical connection in their audio experiences.   The hyperarticulated effects of this energy balance do not wear well in the ears, minds, and hearts of those looking for a more musical connection in their audio experiences.   The Effect of Cable Length on Bandwidth and Resonance An extremely short cable without networks will have wider bandwidth than a longer cable of the same type because the shorter cable will have less inductance and capacitance. As discussed earlier, extremely wide bandwidth cables are subject to noise infiltration and resonant behavior and sonic byproducts that do not serve music. Extremely short cables without networks will sound more alike than they will sound different because of their similar bandwidth and resonant characteristics. In our opinion, they will tend to transfer an audio signal so that it is more like a hi fi experience than it is a musical experience. Contrary to popular opinion then, shorter is not necessarily better from a musical standpoint. In cables without networks, a longer cable will tend to sound less bright and fuller because it will have more inductance and hence less bandwidth and a lower resonant point than a shorter cable. The same sonic pitfalls that apply to the "shorter is better" perspective, also apply to "Cable Comparator" tests. From an electrical perspective the cable comparator behaves like an extremely short piece of cable. In other words, the cable comparator will have extremely wide bandwidth and will have a relatively high resonant point. A typical cable without a network will most closely resemble the electrical characteristics of the cable comparator than will a cable with a properly designed network. It also follows that the shorter the piece of cable, the more it will resemble the sound of the comparator. The basic premise of this comparison is based upon an assumption that a short cable is better from a musical performance perspective which as we have discussed earlier, is not the case at least from the point of view of our extensive tests and listening. The Ideal Cable Length for Audio Applications There is, in fact, an ideal length for any type of cable which will establish the proper relationship between capacitance and inductance; i. e., ideal bandwidth and a resonant point that is as low as possible for the application. If this specific "ideal" length of cable is compensated properly in its natural roll-off region with a network, it will exhibit very uniform group delay characteristics throughout its entire usable bandwidth; i.e., phase, imaging, timing of harmonics to fundamentals, etc. will be true to the source.   Extremely short cables without networks ... will tend to transfer an audio signal so that it is more like a hi fi experience than it is a musical experience.   Every Transparent Cable regardless of length (with the exception of inordinately long cables) is tuned so that it achieves the same electrical characteristics as an "ideal" length of cable for the application, and then it is properly compensated in its roll-off region to achieve uniform group delay characteristics. We optimize interconnects longer than 35 feet and speaker cables longer than 25 feet to sound extremely wonderful in their own right. Extra long Transparent Cables will definitely have a performance edge over uncompensated extremely long lengths of cables. Because we typically use a variety of different lengths of cables in today's complex audio and video systems, our musical interests are better served by choosing cables that have all been tuned to achieve the electrical characteristics of an "ideal" length of cable. If music is the priority, then Transparent Cable has to be the choice.   From an electrical perspective the cable comparator behaves like an extremely short piece of cable.   Top Strand and Conductor Technology Conductor material should be pure and consistent, and the conductor surface should be smooth and uniform for best signal transfer. In our opinion, pure silver conductors do not possess inherent qualities that make them a better conductor of music range signals than copper conductors. For audio applications, pure silver will usually require more compensation than many copper conductor configurations, and the cost of pure silver is exorbitant. The conductors in Transparent Cables consist of many strands of single gauge, precision extruded, oxygen free copper. Each strand is annealed to provide an extremely smooth and uniform surface. The strand bundles are precisely wound around a center core of dielectric. Dielectric Materials Precision extruded teflon has superior dielectric insulation properties compared to just about any other material except air, but cables with sufficient air insulation would be very bulky and difficult to manufacture with consistent results. Teflon works very well on interconnects which require a relatively thin layer to insulate them properly, but teflon insulation would result in a very stiff and difficult to use speaker cable. Transparent Interconnects have teflon insulation, and Transparent Speaker Cables have polypropylene insulation. Polypropylene has nearly the same excellent insulation properties as teflon, but it is a lot more flexible in the quantities required for proper speaker cable construction. Laser micrometers insure even dielectric extrusions on all Transparent Cables.   Every Transparent Cable regardless of length ... is tuned so that it achieves the same electrical characteristics as an IDEAL length of cable   Cable Geometry As discussed earlier, twisted pair technology results in superior audio range performance because of the nulling effect of + and - conductor proximity. Many audio cables provide twisted pair technology. The precision and consistency of the twists are very important to achieving as much nulling as possible and to insure that any two sections of cable of the same length will exhibit the same relationship of inductance to capacitance. The cable jacket must be tightly and precision extruded around the twisted pair to hold the twisted pair firmly in place. The tight jacket insures that cables will maintain their intended electrical characteristics even when the cable is flexed or bent as in home audio installations. Transparent Cables consist of twisted pairs that are precision machine wound to our exact specifications. Cable jackets are pressure extruded to hold conductors firmly in place when the cable is bent or twisted. Transparent Cables have amazingly consistent electrical characteristics from sample to sample. They also exhibit rock solid electrical characteristics when they are bent or twisted. These manufacturing techniques allow us to fit every performance level and length of Transparent Cable with a precision designed network that will result in the same high standards of musical performance from application to application. Soldering Techniques We do not use solder pots or extremely hot soldering irons to construct Transparent Cable. We carefully temper the strands in each conductor with heat controlled soldering irons, and we use only enough heat to flow high purity 2% silver solder. Out of the many soldering techniques we have tested with time delay reflectometry, our heat-controlled methods seem to provide the best signal transfer results.   Transparent Cables have amazingly consistent electrical characteristics from sample to sample.   Please refer to the FAQ for answers to commonly asked questions regarding specific selection choices of Transparent products, services, and special terminations. If you have additional technical questions please send us an e-mail at transparent@transparentcable.com. Top