The classic contemporary examples of sidechain would be the aforementioned French-style EDM compression, where a kick drum is fed to the sidechain input of a compressor, while the rest of the mix (or a large proportion of it) is fed through the main inputs.
The key point to note is that signal processors like compressors and gates have both an audio input – which was used as the input for the signal need to be processed – and a so-called ‘Sidechain’ or ‘External Key’ input that allowed the engineer direct access to the ‘listening’ circuitry.Īs such, this meant there could be a distinction between the signal being processed and the signal being used to drive the signal processor like a compressor. Sidechaining as a technique that originates from the days of dedicated studio hardware, where a device would have multiple inputs (more on this in a bit) and engineers had complete flexibility in respect to how they routed a signal around the studio.
