Or you can simply buy a 1/4" - rca jack giving your the ability to use your ipod or your laptop. From my experience using a Numark mixdeck a few times at gigs, people who notice the dock will start asking to charge their iphone which is annoying.
It's a 1/8" to RCA jack. I own a few, that's what I usually use. I've had distortion issues with it sometimes since it isn't really designed to be amplified to a PA system. The dock seems more feasible for distortion-less play, I've seen my co-workers using the bigger IDJ2 setup and it works quite well for their application. I'd just politely refuse any requests to charge iphones.
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