A Vocoder is an electronic speech synthesiser which takes both a modulator and a carrier, and blends them together, resulting in a heavily effected hybrid synth/vocal sound, hence the name origin ‘vocal’ and ‘coder’. A modulator is a signal which controls the filters of the carrier, and it is usually sung or spoken vocals. A carrier can be anything depending on the plugin or hardware, but it is typically a synth patch played through a MIDI keyboard. The way this works is somewhat similar to side-chain compression, as you have a reference signal or ‘key input’ which controls the level of compression on the affected signal.
Vocoders are used in both studio productions and live shows. The use of vocoders has been prominent in various styles of electronic music productions for many years. The very first iterations of electronic speech synthesisers can be traced back to the innovations of Homer Dudley in the late 1930’s, but the first implementations of vocoders in music productions didn’t occur until the 60’s, the first of which was developed by Wendy Carlos and Robert Moog. Some of the first artists to use such effects include Afrika Bambaataa, Herbie Hancock & Kraftwork. Vocoder effects were also used in the score of Stanley Kubrick’s controversial classic “A Clockwork Orange”.
An alternative and vastly creative use of vocoders is using the effect on sounds which are not vocals to create something new. Recently, Mike Shinoda from Linkin Park created a new sound from a cowbell loop using a vocoder and some other guitar pedal effects:
Happy, little, musical, accidents.
Inspired by this, I had a go at experimenting with a vocoder myself. Similar to Shinoda, I also ran some percussion loops through a vocoder, except the results were different because I used a different carrier source signal:
Fun fact, it was believed for a long time that Cher’s vocals on her song “Believe” were vocoded, but it turns out they were just extremely dramatic settings on the equally famous and infamous Auto-Tune by Antares, which is a pitch correction effect plugin – NOT to be confused with electronic speech synthesisers.
I really enjoyed experimenting with this vocoder plugin, and I’d be interested in looking at some more advanced plugins in the future.
Apple Inc. (2010, January) Logic Studio: Instruments – A Brief Vocoder History [Online Documentation] Retrieved from http://documentation.apple.com/en/logicstudio/instruments/index.html#chapter=10%26section=10%26tasks=true
FutureMusic (2015, September, 30) A brief history of vocal effects [Magazine Article] Retrieved from http://www.innovativesynthesis.com/introduction-to-vocoders/
Wikipedia (2017, April, 23) Believe (Cher Song) [Wiki Article] Retrieved from http://en.wikipedia.org/wiki/Believe_(Cher_song)
Wikipedia (2017, April, 26) Vocoder [Wiki Article] Retrieved from http://en.wikipedia.org/wiki/Vocoder