The audio cable directly transmits the power signal. Due to the large current, the copper core of the wire is usually thicker. In order to ensure high frequency passage and reduce resistance attenuation, silver-plated, gold-plated or oxygen-free copper wires are mostly used. Audio cables are generally divided into copper-plated audio cables and oxygen-free copper audio cables. Audio cables mainly transmit power signals, so speaker cables are required to have excellent conductivity and high-quality transmission capabilities. The audio cable is also called the speaker cable, which is mainly used to connect the power amplifier and the main speaker, surround speakers in the home theater, that is, to connect the power amplifier and the speakers. Compared with video cables and audio cables, its current signal is relatively large. Due to the large signal amplitude, audio cables often have no shielding layer. For this kind of wire, the key is to reduce its resistance, because the output resistance of modern power amplifiers is very low, so the requirements for speaker wire will also increase, such as the use of large cross-sectional area or multi-stranded wire. At present, oxygen-free copper audio cables, also known as gold and silver cables, are more mainstream and have lower resistance. Audio gold and silver cables usually have no shielding layer, because the current signal flowing through them is larger than that of audio cables and video cables, and the signal amplitude is very large. The most important thing is to reduce the resistance of the line. The impedance at the output of the power amplifier is very low. The audio line passes low-power, low-current signals, and has high impedance and is susceptible to interference. Therefore, it is generally a shielded wire, and the wire is relatively thin. Audio cables usually have a shielding layer, but audio cables often do not have a shielding layer. The key is to reduce resistance. Among the deep blue highway audio cables, the more expensive is the dedicated oxygen-free copper speaker cable, which is mainly characterized by good conductivity and low resistivity.

The audio signal line can be used to connect the line between mobile phones, CD players, MP3 music output signal devices and power amplifiers. Speaker cables are mainly used for various speakers, PA projects, home theater connections, and public space broadcasting systems.