Yes, this has been discussed before. The main problem is that CD changers have proprietary control interfaces, and you'd need a different interface device for each brand of CD player. No matter what, you would need to create some hardware that goes between the serial port and the CD changer, because the changers don't talk "regular serial". Then you would have to write the necessary software to control the hardware.

But if you're willing to reverse-engineer the CD changer's proprietary interface (it's been done before I'm sure), and willing to create the hardware interface, and willing to write the software, then yes, it can be done. It's just not a trivial task.

Empeg doesn't have this capability in the product because of the proprietary nature of changers, and because the product is targeted as something that allows you to get rid of the need to carry your CDs in the car.

PS: They do make add-on changers with wired/wireless remote control interfaces. You could easily use one of these combined with the empeg. You just would't be able to use the Empeg's front panel to control it, you'd have to use the controller that came with the changer.

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Tony Fabris