But the need for faders and knobs remains, and has inspired two slightly weird-looking gadgets.

ENGADGET: Music Thing: Frontier Alphatrack

Channel faders make it simple to switch between tracks or blend the music together in a true DJ fashion.

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Post-fader: the effects are applied to the sound after the fader, allowing the sound to fade out naturally rather than stopping suddenly when the DJ cuts the source audio with the faders.

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Nothing wiggles, nothing feels like it's in danger of breaking off, and all of the materials seem to be there for a reason: the tops of the jog wheels are grooved to feel like vinyl, for instance, and knobs, faders, and buttons are all coated in non-slip rubber or plastic.

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In the late '70s, when 24-track recording was possible but there was no reliable way to automate mixing, mixing records was a live performance, with the producer, the engineer and half the band called in to push faders up and down as the track was bounced to the master tape.

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The XDJ-Aero does nothing to undermine that rep -- the metal top finish, solid response of the buttons and luxurious-feeling faders and caps leave you with no doubt that this is a solid bit of kit that should easily withstand the knocks and bumps that come with mobile gigging, or just regular enthusiastic use.

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