How to add amp and subs to factory stereo?

Adding an amplifier and subwoofers to a factory stereo is totally doable! Here's the basic process: Line output converter: Since most factory stereos don't have RCA outputs, you'll need a LOC (Line Output Converter) to convert speaker-level signals to preamp-level signals for your amp Power connections: Run a power cable from your battery through the firewall to the amp location, with an appropriate fuse near the battery Ground connection: Find a solid metal grounding point near your amp Remote turn-on: Connect to a switched 12V source that turns on with your stereo Signal connections: Run RCA cables from the LOC to your amplifier Speaker wiring: Connect your subwoofers to the amplifierThe trickiest part is usually tapping into the correct speaker wires behind the factory stereo—a wiring diagram for your specific vehicle model is super helpful for this!

As someone who's installed several car audio systems, here are my tips for a successful factory stereo amp/sub addition:1. Choose the right LOC: Don't cheap out on the line output converter—a good one like the AudioControl LC2i makes a huge difference in sound quality2. Access factory wiring: Often easier through kick panels or rear deck rather than pulling out the entire head unit3. Setting gains properly: Use a multimeter or oscilloscope to set amplifier gains correctly to avoid distortion4. Sound deadening: Consider adding some sound deadening material to your doors and trunk to reduce rattlesWhat many people don't realize is that you can often get a much cleaner installation by using a factory integration processor rather than a simple LOC. These devices provide better signal processing and often include features like equalization and time correction that can dramatically improve sound quality. Crutchfield's installation guides were incredibly helpful when I did my first installation!