Of all the cable types in an audio system, speaker cables operate in the most demanding electrical environment and are therefore the category where cable specification has the most genuine relevance. This does not mean expensive speaker cables are necessary — it means understanding the relevant parameters is more important here than elsewhere.
Speaker cables carry high-current signals between the amplifier’s output and the speaker’s terminals. Unlike interconnects — which carry small-amplitude, high-impedance signals — speaker cables must deliver significant current into low-impedance loads with minimal voltage loss. The amplifier’s damping factor — its ability to control woofer cone motion — is directly affected by the resistance of the speaker cable, since this resistance adds to the amplifier’s output impedance in series.
Cable resistance is therefore a meaningful specification for speaker cables. A long run of thin cable — high resistance per metre — will measurably increase the effective source impedance seen by the speaker, reduce damping, and introduce a frequency-dependent voltage loss where the speaker impedance dips. This is not theoretical: it is calculable. For a speaker with a nominal 4-ohm impedance dipping to 3 ohms in the bass, a cable with 0.3 ohms total resistance represents 10% of the load impedance — a non-trivial loss.
The practical solution is not an expensive cable — it is an adequately specified one. Cable resistance is determined by conductor cross-section and length. A speaker cable run of 3 metres in each direction using 2.5mm² cross-section copper conductor has a total loop resistance of approximately 0.025 ohms — negligible by any standard. A 4mm² cable at the same length halves this figure. The cost difference between these cables and premium audiophile speaker cables of equivalent gauge is many times the engineering justification.
What matters in a speaker cable is cross-section appropriate to the run length, quality termination at connectors, adequate insulation, and reliable contact at the binding post. These requirements are met by well-made cables at modest cost.