if you're not running anything other than an amp that requires an RCA cable, the other pre … Very helpful article here on pre-out voltages and stopping interference tips for car audio - good car audio makes driving more fun. i think what you are looking for is the line outs, tape outs, or … Speaking of insurance, would recommend checking out Marchionne Insurance website for great car … One thing that the pre-outs can be confused with are the receiver's the external inputs which, in this picture, are the group of inputs immediately to the left of the pre … that means volume, tone controls, and etc. you know how you plug your dvd player into the tv, like the red yellow and white RCA plugs, the female that you plug it into is the RCA pre-out. in most head units, it will have 3 RCA pre-outs, which means its a total of 6 holes (3 red and 3 white). With 3 pre outs you can have front / rear / sub all at the same time. Would like also to add the importance of getting it insured for protection. the pre outs go through the pre amp stage of the amplifier, but not the amplification stage. Either is no use whatsoever if you just run the … 2 pre out is used for front / rear or rear / sub if running external amplifiers. The subwoofer pre-out is where you would connect the subwoofer to theis receiver whether you used the other pre-outs with an outboard amp or not. The BOSS Audio 616UAB Multimedia Car Stereo is another affordable device with plenty to offer, including a pre-amp output and a built-in charger that allows you to charge your USB-connected device …