How the groove generator works
Each style is a groove played by several percussion instruments, and every hit is a recording of a real instrument, with several strokes per instrument and more than one sample per stroke. You can turn each instrument on or off and set its volume, change the tempo while it plays, and download whole bars as MP3 or WAV.
Humanize adds small random variations to every hit, a few milliseconds of timing and a little dynamics, as a real percussionist would. Turn it off if you want a perfectly even grid.
Available styles
Choose the style in the Style menu above. The generator starts with one style, and new ones will be added over time.
Catalan rumba
Catalan rumba (rumba catalana) took shape in the 1950s and 60s among the Romani community of Barcelona, in neighbourhoods such as Gràcia, Hostafrancs and the Raval. Musicians like Antonio González “El Pescaílla” and Peret mixed flamenco rumba with Cuban son and guaracha and with rock and roll. Later, bands such as Los Amaya and Gato Pérez kept it alive, and the Gipsy Kings made a close cousin of it famous around the world.
Its signature is the ventilador, a guitar technique in which the right hand alternates strums, muted slaps and thumb hits, so the guitar itself becomes a rhythm section. Hand claps, bongos and congas complete the groove. The music is in 4/4 and usually moves fast, somewhere between 100 and 140 BPM.
In this style each instrument repeats a one-bar pattern (the bell, a two-bar one). Counting the bar in sixteenths, 1 e & a 2 e & a…, this is what you hear:
- Hand claps: one person, one short, dry clap on each of the four beats, each with its own weight: very soft on 1, normal on 2, soft on 3 and strong on 4.
- Cajón: bass tones on 1 and on the “and” of 2, a softer bass on 3, slaps on 2 and 4 (the one on 4 is the strongest hit of the bar) and light ghost notes on the sixteenths in between. Bass on 1 and 2& plus the slap on 4 draw the 3‑3‑2 feel of the ventilador.
- Bongos: the martillo (“hammer”). Index finger on the small drum on 1, 2 and 3, thumb and fingertips on the off-beats, and an open tone on the large drum on 4.
- Congas: the tumbao. Heel and tip strokes keep the eighth notes going, a slap lands on 2 and two open tones close the bar, on 4 (conga) and on the “and” of 4 (tumba).
- Cowbell: the bongo bell pattern. Low mouth strokes on 1 and 3 and neck strokes on 2 and 4, plus the “and” of 4 in one bar and the “and” of 2 in the other. Those two bars follow a 2‑3 clave: the first one matches the two-note side.
How to practise with a groove
- Start slow. Set the tempo well below the song, for example 90–100 BPM, and play the song or your part until it sits with the groove.
- Find the anchor. In every style there is a beat where the strongest hits meet; in Catalan rumba it is beat 4, with the loudest clap, the cajón slap and the open tones. If you drift, listen for it and land there.
- Strip it down. Turn instruments off one at a time and keep the feel. With only one left, you carry the groove yourself.
- Speed up gradually. Raise the tempo 5 BPM at a time up to the speed of the song.
- Take it with you. Download 1 to 10 minutes as MP3 or WAV to practise away from the screen or to load it into your recording software.
To check that your time holds without help, combine it with the gap click metronome, which goes silent for whole bars.
Frequently asked questions
Is the groove generator free? Can I use the files I download?
Yes. It is free and there is no account to create. The samples are public domain (CC0) and the file is generated on your device, so you can use it to practise, in lessons or in your own recordings.
Are these real instruments?
Yes. Every hit is a recording of a real instrument, with several strokes per instrument (for example open tone, slap and heel on the conga) and more than one sample per stroke, so the loop does not sound mechanical.
What tempo range does each style have?
Each style has its own range and starting tempo, always counting quarter notes. Catalan rumba is usually played between 100 and 140 BPM; here it goes from 70 BPM, for slow practice, up to 220 BPM, and starts at 140.
In Catalan rumba, which clave does the cowbell follow?
2-3. The cowbell pattern lasts two bars: the first matches the two-note side of the clave and the second, the three-note side. The other instruments repeat every bar, so the clave only affects the bell.
Why is the download a little longer than the length I chose?
The file always contains whole bars and ends with a final hit on beat 1 that is left to ring out, so it never cuts a note in half. That adds up to one bar and a second or so.
Can I change the tempo or the instruments while it plays?
Yes. Tempo, instruments and volumes change straight away, without stopping the groove. Changing the style restarts it.
Does it work on my phone and offline?
Yes. It works in the browser on phones, tablets and computers. On iPhone, tap Play to start the sound. After your first visit the groove also plays without a connection.
Will there be more styles?
Yes. Each style is a simple data file, and more grooves, such as pop-rock and rock, will be added.