||This article needs additional citations for verification. (July 2006)|
Hoover sound refers to a particular synthesizer sound in electronic music, commonly used in Hard House music and other styles. Originally called the "Mentasm" or "Dominator", the name that stuck was the one likening the sound to that of a vacuum cleaner.
The sound 
The Hoover is a complex waveform that can be created with three oscillators, each spaced an octave apart, a heavy use of pulse-width modulation and a thick chorus effect. The sound is characterised by its thick swirliness that stems from a fast LFO controlling the PWM and the chorus and was originally created by Eric Persing for the Roland Alpha Juno.
It is traditionally created with the Roland Alpha Juno-2, Alpha Juno 1, or rack mount version MKS-50 synthesizer using the built-in What the patch. The hoover sound generated on these synthesizers are unique for the use of "PWM" sawtooth wave, which inserts flat segments of variable width into a sawtooth waveform. Where a Juno-2 is not available, Hoover sounds are sometimes produced by using samples of Alpha Juno-2 Hoovers and Granular synthesis on these samples. The Hoover has become something of a fetishized item in certain circles of music production (not unlike the sound of the Roland TB-303).
History and popularization 
The hoover sound is believed to first have appeared in a commercial production in "Mentasm" by Second Phase (1991), produced in a collaboration between Joey Beltram and Mundo Muzique, and sometimes is referred to as a "mentasm". However, mentasm normally refers to the sound sampled from this tune and re-used.
Another notable use of a record using a hoover sound is "Dominator" by Dutch techno pioneers Human Resource. This track gained fame in 1991 and became a top 10 hit worldwide. Characteristic for this track was not only the Hoover, but also the over the top rap: "I'm bigger and bolder and rougher and tougher, in other words sucker there is no other... I'm the one and only dominator.. Wanna kiss myself!"
The hoover sound has also appeared on the Prodigy's debut single "Charly" and in the song "Warp 1.9" by The Bloody Beetroots and Steve Aoki. It has been used by The Time Frequency on "Ectoplasm", the b-side to "Such A Phantasy".
Hoover replacements 
Although the original hoover sound was created with a Roland Alpha Juno 2 there are several replacements to choose from that include, but are certainly not limited to, the Alpha Juno 1, Alpha Juno 2, MKS-50 (Rack version of the Alpha Junos), and the JP-8000. The new Roland Juno G has a few presets that feature the Hoover sound.
Virtual Instruments 
Software synthesizers can create similar sounds. Here is a selection of them:
- Trilian by Spectrasonics
- Kv331 Audio SynthMaster
- Pro-Sounds PS-1
- Audjoo Helix
- JBM Hoovermaker
- JxPlugins JX220
- Lennar Digital's Sylenth1
- Native Instruments' Massive
- Reaktor using the Razor ensemble with the 'Hoover' oscillator, or the Staubsauger ensemble
- reFX JunoX2
- reFX Vanguard
- Rob Papen's Predator
- Tone2 FireBird
- Tone2 Gladiator
- Tone2 ElectraX
- Tone2 Saurus
- Image-Line Sytrus
- Reason stock synth called "Thor"
- Audiooxygen Gemini
- PhutureTone Phutura
- MuTools MUX
- u-he Diva (Can emulate the actual Alpha Juno)
- A Hoover patch for Native Instrument's Massive
- An original Hoover sound bank for Native Instrument's Kontakt and EXS-24
- Dubspot Video Tutorial: Reverse Engineering the Hoover sound - Using The Bloody Beetroots and Steve Aoki's "Warp 1.9" as example
- Reverse-engineering the rave hoover - includes some technical analysis of the sound