I have both Deerslayer and my wing set up with the Amplirider, pre-amp and mixer. No extra cables required - everything plugs in with mini-stereo plugs. Mixes 3 devices. $65 including shipping when I bought mine a couple years ago. They are at
http://www.electric-avenues.com/amplirider.htmlBTW I usually use my Zumo 550 for tunes nowadays, though both bikes will use any player that has mini-stereo plug outputs - so also use Ipod, Riovolt portable disc player, and Archos MP3 player (now retired).

From my audio install page at
http://www.horseapple.com/Valkyrie/Tech_Tips/Jammin_with_Blaupunkt/jammin_with_blaupunkt.html -
Searching for various pre-amps that would fit my need, I found I think the perfect pre-amp for this application - and many others in fact, so I bought another for my wing. The AmpliRider, found for $65 incl shipping 7/09, at
http://www.electric-avenues.com/amplirider.html This unit serves the same function as the Kennedy Cell Set which I had already bought for my wing, and never bothered to install yet. For MUCH more $$$$. Kennedy wants you to buy seperate adapters for every connection at prices I just won't pay - I was going to hard wire everything, but now, I can just plug in all the mini-stereo plugs! It's a small amplifier, with all mini-stereo connectors except the power and ground which you hard-wire. It has 3 inputs that it will mix and output to the single output (you can use for say radar, GPS audio, and music), and a remote volume control you can put anywhere. Very well made, solid, looks like ABS plastic enclosures - compact and available with different wire lengths. I asked Gary for some extra short volume wires on the 2nd one I bought - now I'll use the longer wires for the wing and sell the never-installed Kennedy. The Wing install, had previously required a ground loop isolator to eliminate a buzz for the input from first a RioVolt SP250 player, followed by an Archos Recorder, and now the Ipod Classic. The input for the radar - and I suspect the GPS (though I didn't connect it - don't need a woman's voice nagging me where to turn), required an isolator transformer - radio Shack P/N 273-1374, $3.99, and a couple mono solder plugs and audio wire. (Gary just said, he will mention on the AmpliRider's website that isolation cables may be needed for some detectors, and that they are available prewired.) I also needed a mono wire with male mini plugs both ends, and a mono-stereo female-male (respectively) adapter plug to adapt the mono signal from the radar to stereo to import into the AmpliRider. Used here, the tunes have more than double the volume from before, and the sound is cleaner, and I have a volume knob instead of that useless slide-your-finger volume control on the Ipod. The radar signal is plenty loud, cannot be missed.