Signal Loss Calculator — Audio Cable Attenuation

For analogue audio, losses under 1 dB are generally inaudible. Losses of 1-3 dB may be noticeable in critical listening. Above 3 dB, signal degradation becomes significant. High-frequency losses tend to be more noticeable than broadband attenuation.

Cable capacitance creates a low-pass filter with the source impedance. Higher frequencies see more attenuation because capacitive reactance decreases with frequency. This effect is most pronounced with high-impedance sources like passive guitar pickups.

For analogue connections, capacitance affects tone. For digital connections (AES3, S/PDIF), what matters is matching the characteristic impedance (110Ω for AES3, 75Ω for S/PDIF). Impedance mismatches cause reflections and data errors.

No — the 1 kHz and 10 kHz loss-per-metre figures here are indicative estimates to give a rough feel for relative cable performance, not values taken from a specific manufacturer datasheet. For real analogue runs, 1 kHz attenuation is governed by conductor resistance and is negligible (hundredths of a dB) over normal lengths. The meaningful result for analogue cable is the high-frequency -3 dB rolloff, which is computed directly from your source impedance and the total cable capacitance. For exact loss, use the cable resistance and capacitance from the manufacturer datasheet (e.g. Belden, Mogami, Canare).

Speaker-cable loss is almost entirely resistive and frequency-independent across the audio band. A useful rule of thumb is that about 1 Ω of total cable resistance costs roughly 1 dB into an 8 Ω load: loss (dB) = 20·log10(Zload / (Zload + Rcable)). The thicker the conductor (lower AWG) and the shorter the run, the lower the loss — wire gauge and length matter, not a fixed dB per metre.