Found something to do with my boredom and 5 empty altoid tins http://www.instructables.com/id/Altoids-Tin-18-Stereo-Mixer/
Altoids Tin 1/8" Stereo Mixer
My car stereo has only one 'Aux' input, but I have several gadgets that I like to hear on a trip without swapping cables: MP3 Player, talking GPS, Blackberry, XM player, Kindle, etc.I couldn't find a commercial solution, so I came up with this little passive audio mixer that takes 1/8" headphone outputs from up to four devices and safely mixes the signals into one line that can feed a car stereo Aux input, powered speaker or any other amplifier that can take 1/8" stereo output.No batteries are req...
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