Faders
The crossfader is the component of the DJ mixer that is most important to turntablists.
Intro
Early DJ crossfaders were a simple carbon-track design, and contained two pairs of Logarithmic curves. This made the crossfader essentially equivalent to two back-to-back input faders. These were adequate for looping and beat-juggling, but made performing even basic scratches very difficult. In addition, the faders simply weren't designed to withstand the number of cycles a typical turntablist would put them through in a day, let alone a few years. As a result, many/most early scratch DJs used the phono/line selector switch to cut instead.
By the early 90s, performance mixers (such as the mx-2200) had faders with sharper curves, and used a carbon/plastic hybrid design to increase the durability. Still later mixers, such as the Vestax PMC pro series, switched the passive fader design for VCA circuits. These allowed advanced features like control voltage filtering (increasing fader life even further) and curve adjustment.
The current generation of performance mixers have a wide variety of novel non-contact methods of sensing fader position.
Fader requirements
Turntablists have the following requirements in a crossfader :
- Small off-to-on travel distance - the appropriate channel should be fully muted when the fader is in the zero position, and bring the channel to full volume within the first 5mm of wiper travel.
- Low friction - the wiper should move with as little friction as possible.
- High durability - the fader should be able to withstand significant lateral and forward-backward force at all wiper positions.
- Long operational lifecycle - the faders lifecycle should be specified in the millions of operations, ideally tens of millions.