A:AnswerYes, Most stock head units don't have preamp output, so you would just splice the Kicker's signal wires to the appropriate speaker wires. Then select to use High Level inputs on the Kicker Hideaway. Connect the power wire (with fuse) to your battery, and the ground wire to the car's chassis. When installed this way the amp will turn on when it detects input signal. There is no need for a Line Output Converter.
A:AnswerThat's a subjective question. Let me put it this way, it sounds great for an 8" woofer. Do not expect the same sound you would get from a full-enclosure 12'' woofer. But it is much better than just your stock speakers. Very nice sound
A:AnswerI tapped directly into my rear speaker wires without any issues. You also have the option to power the unit with RCA cables. It's capable of receiving either Hi (speaker-level) or Low-level (RCA) signals from your source unit and then you just set the Input Level switch on the side panel to match the outputs of your source unit. If you use RCA cables from the kicker into the back of your stereo, you don't tap into your speakers. If you go that route, you do have to connect the remote turn-on lead using 18 gauge wire from the remote turn-on lead on your source unit to the terminal labeled REM on the power harness. If you tap into your speakers, you don't need the remote turn-on wire and you set the kicker to DC Offset.