A studio rack full of classic compressors including the Shadow Hills Mastering Compressor, Universal Audio 175B, and Urei 1176.Compressors and limiters are some of the most important and versatile tools that any audio engineer can use. Virtually every modern recording uses compression somewhere in the chain of tracking, mixing, and mastering. This ubiquity makes them valuable but also creates confusion when considering the many choices in the marketplace. To help straighten that out, we’ll discuss the main types of compressors and the terminology that explains their usage. The purpose of a compressor is to even out the audio signal in order to tame loud transients and bring up lower-amplitude material. Compressors were born out of necessity to fill that very straightforward role, to protect radio transmitters from overly hot signals, and to keep recordings in a narrower dynamic range that was easier to reproduce on tape or record. Continue reading →