Limiting

Limiting is a form of compression. Limiters use very hard compression ratios (above 8 :1) and very fast attack and release settings, this gives an almost ‘brick wall’ form of compression.
Limiting can be used for all sorts of different things but a good start would be on a bass guitar, this is because the bass forms the main anchor of the mix and a limiter helps to hold its level very consistently.

I often use limiters after compressors just to catch the odd particularly loud note on vocals, guitars bass and real drums.

Limiters are often also used of the overall 2-track mix of a recording, plug-in’s such as the waves L1 Ultramaximizer being the most famous example. These tools should be used with caution, whilst they do increase the loudness of a recording, they also slam the transients and dynamics out of a mix often leaving it flat and fatiguing. The 'loudness war' that tools like these have caused have given limiters a bad name in recent years, however they are still enormously useful tools when used correctly and can very effectively help sit things in a mix where normal compression can’t.

The below images show the effect of heavy limiting on a mix waveform:

Before:

After

You would be forgiven for thinking the above waveform is distorted heavily, but a l lot of commercial recordings actually look worse than this!

Multi-band Compression

A multi-band compressor comprises of a number of independent compressors (usually 3 or 4). Different parts of the frequency spectrum are assigned to the different compressors. So for example, one compressor might only affect th150Hz-1kHz Range.
Multi-band compressors allow for more detailed manipulation of the dynamics of a recording. i.e you could compress the bass end very hard and leave the top end nice and open. However you should use these devices cautiously as you can seriously make a mess of a mix if you are not confident in their use, leaving a mastering engineer unable to sort it. I would avoid using MB compressors in a particularly compromised monitoring system as you may not be able to hear what you are doing!
Typically MB Compression is used at the mastering stage to smooth out the overall 2-track master recording. However, experiment by compressing groups of instruments, personally I like to use them on vocal groups and occasionally on the drum buss.
In final summary you should not be afraid to experiment with compression, the only way to learn any new tool is to use it. Try compressing groups of instruments on busses, try compressors before eq, after eq, before reverb, after reverb, try compressing a compressed signal, limit a compressed signal.
And remember, its not how something sounds on its own, its how its sounds in the track!!!

© Nathan Boddy 2006 unauthorised copying or duplication prohibited.

Go back to articles