How to Make a Hoover Sound: Recreating the Rave Classic

What is a hoover sound?

The hoover is a thick, swirling, slightly out-of-tune synth sound that swoops in pitch, used as a lead or stab in rave, hardcore, gabber, trance and hard house. The name comes from its resemblance to a vacuum cleaner; it was originally called the "Mentasm"^[1].

Its character comes from four things working together: octave-stacked oscillators, heavy pulse-width modulation, a thick chorus and a pitch movement at the start or end of each note. The swirl comes from a fast LFO driving both the PWM and the chorus^[1]. Remove any one of those and it stops sounding like a hoover.

If you have built a supersaw before, the hoover is a close cousin with more motion and a darker, hollower core.

Where does the hoover sound come from?

The hoover comes from a factory preset called "What the" on the Roland Alpha Juno, programmed by Eric Persing. It used the synth's sawtooth PWM together with a pitch envelope^[2].

Roland launched the Alpha Juno in 1985 as a six-voice analog polysynth with one DCO per voice offering saw, square and noise plus a sub-oscillator, a 24 dB/oct resonant low-pass filter and a chorus. Unlike earlier Junos, it could apply pulse width modulation to the sawtooth wave as well as the square^[2]. That PWM saw inserts flat segments of variable width into the sawtooth, which gives the hoover its hollow, rubbery tone^[1].

From joke preset to rave anthem

The sound's first known commercial appearance is "Mentasm" by Second Phase in 1991, a collaboration between Joey Beltram and Mundo Muzique, and Human Resource's "Dominator" took it to a much wider audience the same year^[1]. On "Mentasm" the preset was sampled into a Casio FZ-1 sampler rather than played straight from the synth^[2].

Sonicstate describes "What the" as starting life as a joke preset, and points out that pitched-up hoovers became a mainstay of drum and bass as well as rave^[3].

What makes up the hoover sound?

A modern hoover recreation needs five ingredients: a PWM-style sawtooth, octave layering, fast modulation, a pitch envelope and chorus. The table maps each part of the original to a modern synth setting.

How to make a hoover sound in Vital

Vital has every piece you need, including a waveform warp called Pulse that adjusts the duty cycle of any wavetable^[4]. Applied to a saw, it gets you close to the Alpha Juno's PWM saw.

1. Start from an init patch
   Load the basic saw on oscillator 1. Set the voice to legato so you can play slurred lines, and set the amp envelope to a fast attack, full sustain and 100-300 ms release.
2. Turn on the Pulse warp
   Set the oscillator's wave morph to Pulse and the amount to around 30-50%. The saw gains a flat section and turns hollow and nasal.
3. Modulate the warp with an LFO
   Drag an LFO onto the morph amount at 20-40% depth. Use a sine at roughly 4-8 Hz, or sync it to 1/16 notes if you want the swirl locked to the tempo.
4. Add unison
   Vital's oscillators offer 1 to 16 unison voices with a 0-100% detune control^[4]. Start with 6 voices and 25% detune.
5. Stack an octave
   Copy the oscillator to oscillator 2 and transpose it down 12 semitones at slightly lower level. Add a third copy an octave up at low level for extra buzz.
6. Route an envelope to pitch
   Assign envelope 2 to the pitch of both oscillators with about -7 to -12 semitones of depth, zero sustain and a 80-150 ms decay. Each note now swoops up into pitch.
7. Add heavy chorus
   Turn on the Chorus effect, which runs 4 to 16 voices with two delay times between roughly 1 and 20 ms^[5]. Push depth high and mix to 60-100%.
8. Leave the filter mostly open
   A low-pass at 5-10 kHz with a little drive takes the edge off the unison fizz without killing the buzz.

Translating the recipe to Serum or other synths

The structure carries over to any wavetable or virtual analog synth: a saw with a warp or PWM control that narrows the waveform, an LFO on that warp, unison, an octave layer, an envelope on pitch and a chorus. Names differ, so look for pulse, squeeze or PWM-style warps. For a side-by-side of the two most common choices, see Serum 2 vs Vital.

How do you get the hoover pitch dive?

The hoover's pitch movement comes from two places: an envelope that bends every note up into pitch, and performed pitch bends or glides that dive between notes. The envelope gives the attack its whoop; the bends make the riff.

Set the pitch bend range to 12 semitones so a full wheel throw dives an octave. Then draw pitch bend automation that drops at the end of a phrase, or use legato glide around 80-200 ms so overlapping notes slide. The portamento and glide explainer covers the difference between the two.

• Rise into the note Envelope to pitch, negative depth, short decay. The classic hoover attack.
• Octave drop at phrase end Bend down 12 semitones over one or two beats on the last note of the riff.
• Glide riffs Overlap notes a semitone to a fifth apart with glide on. This is how many rave stabs turn into melodies.
• Pitched-up hoover Play an octave or two higher and shorten the chorus depth for the tighter, nasal tone used in drum and bass.

How do you process a hoover in a mix?

A hoover is already wide and dense, so processing is mostly about control. High-pass it around 100-150 Hz when a separate bass or kick owns the low end, and tame the 2-4 kHz fizz from unison with a gentle cut.

If you want more of the vintage Juno movement, add a second chorus after the synth. TAL-Chorus-LX, for example, is modeled on the Juno-60 chorus^[6], and the free modulation plugin roundup lists more options. Light distortion before a short plate reverb makes the hoover bite in harder genres; long reverbs tend to smear it.

• Mono check Heavy chorus and unison can cancel in mono. Narrow the low octave layer or bring its unison down if the sound collapses.
• Resample it Bounce single hoover notes to audio and play them from a sampler, the way "Mentasm" used a Casio FZ-1. Sample playback adds its own character and makes pitching easier.
• Space in the arrangement Hoovers work best as call-and-response stabs with gaps, not as constant pads.

Which genres still use the hoover?

The hoover lives on in hardcore, gabber, hard house, trance, breakbeat and drum and bass, and it keeps crossing into pop and electronic records. The Wikipedia list of works runs from the 1991 rave hits to 2020s releases by Justice and Lady Gaga^[1].

In rawstyle and hardcore it becomes a distorted, screeching lead; in drum and bass it is usually pitched up and used for short stabs over breakbeats. Both start from the same patch.