Cable Conditioning...how and why

How and why of cable conditioning

All cables consist of some metallic conductor surrounded by an insulated coating intended to prevent contact with other conductors or outside surfaces. The conductor and the coating form a distributed capacitor whose actual numerical value varies with the type of insulated coating and the length of the cable. Typical real world home audio cables are usually in the 10-25 pF per foot range. In addition, the very existence of the conductor also forms a distributed inductance that varies with the length of the conductor and physical configuration/geometry that the conductor takes. A conductor wound into a coil, for example, will exhibit a different value of inductance than a straight conductor.

As various signal voltages are applied to the conductors, the insulated coating (dielectric) will have its electrical characteristics altered. At the molecular level, the electrical charges will redistribute themselves according to the applied signal thereby polarizing the dielectric. This in turn will have some noticeable and measurable effects on the signals passing through the cable. The effects range from not being noticeable to being very apparent depending on the signal frequency components and amplitudes and on the quality of the reproduction equipment and system.

This polarizing of the dielectric gradually becomes rather stable taking on electrical characteristics influenced by the average of frequencies and signal levels passing through the cable. As this happens, the influence on the passing signal no longer becomes random and attains a stable state reducing or minimizing any artifacts caused by the cable. The object of preconditioning is to stabilize the cable dielectric prior to using the cable for serious listening so as to minimize any detrimental effects of the non-polarized dielectric. 

All dielectrics will gradually become depolarized when no longer exposed to periodic signals. How long this takes will depend on the quality of the insulation. You may have experienced the effect yourself when you've taken a long vacation only to return to your Audio reproduction system to find that the sound has seemingly changed. You just can't put your finger on it but the quality of the sound is not what you remember. After listening for a period of time, the old quality seems to return, or maybe you think your ears have simply readjusted. You are likely hearing the result of the cables settling in once again

 

General description of process

Avanti Audio's burn-in sequence provides the quality conscious audio consumer a series of cables ready to provide the very best sonic experience obtainable. Unless otherwise specified by the customer, we will precondition all newly built cables on our custom Cable Conditioning appliance for 48 hours with any analog or digital interconnects (AES/EBU & S/PDIF) and for 72 hours with any speaker or power cables before shipping. The burn-in service is provided free of charge. Once the cables are received and installed in your sound system, please allow between 6 to 12 hours of additional playing time to allow the cables to settle in.

Interconnect cables (RCA, XLR, BNC, DIGITAL and PHONO CABLES) are burned-in using an Avanti Audio proprietary signal that applies a randomly varying frequency and signal amplitude with a bandwidth from DC to over 100kHz and a signal level that varies from zero to 8 volts peak. 

Speaker and other high level signal and power cables are burned-in using an Avanti Audio proprietary signal source that drives the cables at various power levels from zero to 36 watts peak power over an effective frequency range of DC to over 100 kHz. This is a larger frequency range than will be encountered in a real world audio system. Burning-in occurs at voltages and currents that are found in actual day to day operation of the cables.

Because of the extremely wide range of frequencies and a peak power level ranging from +20dBv, for interconnect, to 36 watts for speaker and line cords, the time required to fully condition a set of cables is significantly reduced. Typically, cables can be fully conditioned in just one 48 to 72 hour period.