Turntablism
Crab scratch
A crab is a flare played with the fingers rather than the thumb: the thumb holds tension against the fader while four fingers release it one after another, giving four clicks in one motion.
In practice
The thumb pushes back, four fingers release one at a time — four clicks in a single record motion.
Set the thumb against the far side of the fader so it is always trying to close it, then let the index, middle, ring and little finger tap it open in turn. The thumb is doing the closing on every click, which is why the tension setting matters more here than anywhere else: too light and the fader never returns, too heavy and the fingers cannot beat it. Start with two fingers and a slow record, and only add the third and fourth when the first two are even — an uneven crab is worse than a clean two-click flare.
Thumb closes
On every click
Four fingers
Open in sequence
Two first
Add fingers when even
Where these come from: Technique convention on scratch-oriented mixers, not catalog figures. For what we can measure, see the one and two-click versions.
Why it matters
It is the fastest thing a fader hand can do, and the reason is mechanical rather than musical — four fingers firing in sequence produce clicks faster than any single digit can move back and forth. The record hand carries on at the same speed it always did.
It also puts a hard requirement on the mixer. Four clicks inside one record motion needs a very short cut-in distance and light, consistent fader tension, which is exactly what a scratch mixer is built to provide and what a club mixer usually is not.
Frequently asked
What is the difference between a crab and a flare?+
How the clicks are produced. A flare uses one digit moving back and forth; a crab holds the fader closed with the thumb and releases it with four fingers in turn.
Why is it called a crab?+
From the sideways scuttling motion the fingers make across the crossfader cap as each one releases it in sequence.
Do you need a scratch mixer to crab?+
Effectively yes. Four clicks inside one record motion needs a very short cut-in distance and adjustable fader tension, which club mixers rarely have.
Related terms
Scratch
A scratch is a sound made by moving a record back and forth under the needle while the crossfader or channel fader cuts it in and out. The hand sets the pitch; the fader sets the rhythm.
Flare scratch
A flare starts with the fader open and clicks it shut one or more times mid-motion, so the sound is interrupted rather than started. One click is a one-click flare, two is a two-click.
Crossfader
The crossfader is the horizontal fader that blends between two channels. At one end you hear only the left assignment, at the other only the right, and a curve control sets how abruptly the handover happens in between.
Hamster crossfader
Hamster is a crossfader wired in reverse, so the left deck lives on the right side of the fader. Scratch DJs run it because it puts the cut on the pull rather than the push.
Explore: Mixing guides · Hamster crossfader · BPM tapper · All DJ terms