Cross-talk

In electronics, crosstalk is any phenomenon by which a signal transmitted on one circuit or channel of a transmission system creates an undesired effect in another circuit or channel. Crosstalk is usually caused by undesired capacitive, inductive, or conductive coupling from one circuit, part of a circuit, or channel, to another.

In structured cabling, crosstalk can refer to electromagnetic interference from one unshielded twisted pair to another twisted pair, normally running in parallel.

In stereo audio reproduction crosstalk can refer to signal leaking across from one program channel to another, reducing channel separation and stereo imaging. This is an electrical effect and can be quantified with a crosstalk measurement.

Interchannel crosstalk applies between the two channels of a stereo system, and is usually not very important on modern systems, though it was hard to keep below the desired figure of -30 dB or so on vinyl recordings and FM radio.

Crosstalk between channels in mixing consoles, and between studio feeds is much more of a problem, as these are likely to be carrying very different programmes or material.

Crosstalk measurement is made on audio systems to determine the amount of signal leaking across from one channel to another.

The IBA drew up a weighting curve for use in crosstalk measurement that gives due emphasis to the subjective audibility of different frequencies, as shown here. This is still in use, despite the demise of the IBA, and in the absence of any international standards is worth adopting.

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