Recording Tips: Limiters

If you have spent any amount of time recording and mixing, you have likely tried to keep a sound from clipping or tried to boost the overall volume of a recorded sound only to have it clip because of a small section or a single sound that tends to be much louder. We’ve already covered two types of compression, basic and side-chain, now I’d like to discuss limiters, which will help with the above issues.

A limiter is a compressor that is typically set to a higher ratio and faster attack (see compressor basics). The goal of a limiter is to “limit” a sound to a specific top volume. Limiting effectively reduces the dynamic range of a sound, this means that if set correctly, it will turn down the louder sections to bring their volume closer to the softer sections. Limiters are used frequently in live sound applications to prevent sounds that are too loud from damaging speakers. In a studio setting limiters are often used as a tool to reduce louder sounds so that the volume of the track as a whole can be increased without clipping or distorting. We will focus here on the studio usage only.

A compressor begins limiting once the ratio is set above 5:1 although it is usually a higher ratio setting, closer to 10:1. Also, attack times are generally much faster. To set up a limiter, start by setting your threshold (or ceiling) to the dB level that you want the sound to start to being effected. An example of this would be if you had a sound recorded where the majority of the sound was below -10 dB, with some areas that were around -2 dB and you wanted the volumes of those sections to be closer to the rest of the mix, you would set your threshold somewhere below -2 dB, but probably not more than -10 dB. Next, adjust your ratio to the desired amount of effect you want to use; 10:1 is a good starting point. Now you will use a fairly quick attack setting (this will be a “to taste” adjustment) to tell the limiter how quickly you want the effect to be executed on the sound. Finally, you can use a make-up gain to increase the overall sound of the newly limited track, which should provide for an overall higher volume without clipping. If you limit too much and use an attack time that is too fast, the result will likely be undesirable.

Limiting is a great way to protect speakers, smooth out performances and increase volume. Remember there is no standard setting for any two sounds, so spend some time tweaking the parameters to get the best effect possible. Try not to use more limiting than is necessary as the goal is to improve the overall mix without being overly obvious. The untrained ear should have no idea that it is there at all (unless that’s desired goal).