The best of both worlds? Parallel compression allows you to boost the impact of signals without losing all their dynamics.
If you’ve ever played with the mix control on a compressor plug-in, you’ve already discovered parallel compression. It’s actually quite a simple idea – blending a compressed signal back in with the original uncompressed version of itself – but it’s a devastatingly effective tool for adding punch and impact to tracks without flattening out the dynamics of the signal.
The origin of the technique is disputed, but the reason it works is beyond doubt: the compressed signal effectively fills in the gaps during quieter parts of the recording, while the uncompressed version retains the detail and transient character of the original. It’s a process that can be applied to almost any sound, but drum or percussion groups are a great starting point.
The sound of parallel compression is by no means dated, but you’ll hear it all over classic mixes from the 70s and 80s – in fact, the technique was so popular with Manhattan mix engineers back in the golden age of big budget rock and pop recordings that you’ll still occasionally hear it referred to as ‘New York compression’.
Back in the day, setting up parallel compression involved splitting audio signals across multiple channels of a mixing desk. Nowadays, the vast majority of compressor plug-ins include a wet/dry mix control that effectively allows you to create parallel compression effects in seconds. Even if your chosen compressor doesn’t have a mix control, it’s quick and easy to route a signal to an aux send in your DAW and apply the compressor on that aux channel. Given how easy it is to achieve, parallel compression should be a go-to whenever you’re looking to add punch and impact to your mix.
What’s particularly pleasing about the technique is just how heavy-handed you can afford to be with the compression on the processed signal. Most of the time we’d be looking for a certain degree of precise control when compressing a drum bus or a vocal, in order to avoid making it sound squashed or unrealistically flattened. With parallel compression, you can go wild. Feel free to go ahead and smash the living daylights out of that drum group if you like, then blend it back together with the uncompressed version in order to strike a balance between dynamic range and pulverised punch.
There are no rules here, just experiment and go with whatever sounds best. You can even apply the process to the entire mix bus if you like.