USC
About this Article
Written by: James Bunning
Written on: December 7th, 2016
Tags: lifestyle, computer engineering, music, sound engineering
Thumbnail by: London Guitar Academy/London Guitar Academy
About the Author
James Bunning was a student at the University of Southern California at the time this article was written.
Also in this Issue
To Float or Not to Float?Written by: Sabrina Winarko
Cryptography and Communication Security in a Digital AgeWritten by: Patrick Vanderwall
The Computation of Love: Finding Your Soul Mate OnlineWritten by: Melisa Osborne
The Future of SurfingWritten by: Christian Lee
Stay Connected

Volume XVIII Issue II > The Battle of Sound

How Do Music Producers Make Recordings Louder?

While experimenting with ways to make recordings stand out on 1950s jukeboxes and radios, sound engineers figured out that in order to make a song sound louder, they actually needed to start by turning the volume down, not up. In every genre of music from classical to jazz to rock and roll, songs have dynamics, so parts of the song are deliberately played at different volumes by the recording artists for effect. Although these loud and quiet sections give music a sense of excitement, movement, and emotional punch, they also presented a problem for early sound engineers. If a song had a large dynamic range, or a wide gap between the softest and loudest moments, a music producer could only push the recording level as high as the loudest transients, such as a drum hit or trumpet blast. Boosting the audio any higher than those peak levels would cause the signal to distort. Therefore, a singer belting out a note in one part of a song would severely limit how much a sound engineer could raise the level of the quieter parts. Sound engineers needed to devise a way to turn up the quieter sections of an audio signal while holding the pesky peaks at bay.
To solve this problem, sound engineers developed a studio trick known as dynamic range compression. While recording music in real time or mixing already recorded tracks, 1950s and 1960s sound engineers fed audio through a piece of electronic hardware called a compressor. By setting the compressor’s threshold control to a certain level, the audio engineer could make the compressor act like a brick ceiling, reducing the level of any mischievous audio peaks that tried to jump above it. After bringing down the loudest parts of the audio signal, the compressor then boosted the entire signal level back up to the original volume, transforming the quieter parts to sound closer in volume to the peaks. By reducing the dynamic range of a song through compression, sound engineers could now effectively increase the average level of music recordings.
James Bunning/Illumin
Figur​e 2: Dynamic range compression applied to "Rich Girl" by Hall & Oates (1976).