Interconnect cables — the signal cables connecting source components, preamplifiers, and power amplifiers — operate in a signal environment that is fundamentally forgiving of cable imperfection. Understanding why puts the claims made for expensive interconnects in their correct context.
A line-level audio signal between components typically operates at signal levels between 0.5 and 2 volts RMS. The signal-to-noise ratio of the components at each end of the cable is generally the dominant limitation on the system’s noise floor — not the cable. The crosstalk between channels, the self-noise of the cable, and the cable’s contribution to the overall noise floor are, in a well-designed interconnect of any reasonable quality, below the noise threshold of the components themselves.
The electrical parameters that could theoretically cause an interconnect cable to alter the signal — resistance, capacitance, and inductance — are well within audible thresholds for any cable of adequate construction and moderate length. A 1-metre interconnect of standard construction has a resistance of a few milliohms, a capacitance of perhaps 100 to 150 picofarads, and an inductance that is negligible at audio frequencies. These values produce no measurable effect on the audio signal when connected between components of typical impedance.
Premium interconnect manufacturers address this situation in one of two ways. Some focus on genuine engineering refinements — improved shielding, lower noise floor, better connector metallurgy and contact design — that represent real, if often marginal, improvements. Others focus on materials and construction features whose claimed sonic benefits have no basis in electrical theory or measurement: oxygen-free copper of increasingly high purity grades, directional cable construction, cryogenic treatment, and conductor geometries marketed with physics terminology applied in ways that do not hold up to scrutiny.
The first category merits consideration for specific applications where shielding or noise performance is genuinely critical. The second does not. The engineering is not ambiguous.