Finally decided to do this project on my own, and boy did it make a HUGE difference. Yes we all know the HU is a pile of crap. I always read how much it would improve the sound quality of the stock system with a simple HU replacement. I completely underestimated the difference it would be. Here is my install list. Pioneer W4400nex (Wireless carplay/android Auto) Alpine KTP-445U (Power Pack) Kenwood P10-300 Harness I previously bought the Alpine power pack about a year ago, but was confused on the wiring so i just let it sit on the shelf. I eventually got so frustrated with the stock system in the 2016 WRX that i started to see how much it would cost to have it installed. I was quoted $120 and i thought that was to much for this type of amp. So for some un-logical reason....i decided to just replace the HU, install the amp, and install a sub/amp combo on my own. I bought most of everything off of Crutchfield and amazon. I did buy all my harnesses from Autoharnesshouse which made it a true plug and play install. He also was extremely helpful when i had a couple questions before i started the install. I pre-wired and ran my wires for my sub one weekend and then completed the install the following weekend and really only took a few hours, but was a very straight forward install. The Pioneer HU with wireless carplay is amazing. My phone is connected probably within 12-15 sec from from when i start the car. Usually with Starlink, it would literally be a good min and that's if it links at all. The sound quality of my speakers added so much depth and clarity...I mean i actually have some Bass coming out of them now lol. I drove that around for a week before installing the amp. The only real difference i heard with the Alpine Power Pack was that it just increased the volume of the speakers themselves. The huge improvement was with the actual HU swap, and i was able to retain all stock functionality of the car (Steering wheel controls, back up camera, USB) I am still contemplating on installing different front speakers as i have read that the tweeters are not true tweeters and might round out the system over all. Has anyone installed different speakers in the 2015+ with a different HU? How much of an improvement could i expect from it?
Very cool. I have a 2017 WRX Limited (without the HK nav/sound system) I'd be interested in just changing the HU so I can have Android Auto or Apple Carplay for the improved connectivity and porting my navigation to a bigger screen. Automotive electrical is not my strong point, so I've always been leery of trying the modification. I'm not much of an audiophile so I'd likely not bother to upgrade anything other than the HU. Navigation is something I did miss not having in my car. Looks like the Pioneer W6400 Nex adds navigation for $100 more. Kind of tempting...
You can't achieve your goals if you don't take that chance So go pry open that trunk and get those amps
As long as you're ok using your mobile data, use your phone with android auto/carplay for navigation and save the $100. The only benefit of having a dedicated nav would be in areas where you have spotty mobile signals, imho. The wireless features of the new line of Pioneers is really convenient, you will not have to attach a cable to your phone to have full functionality of your device. I was a little leery as well, but with all the tutorials out there along with all the harnesses....it was basically plug and play. Well worth the investment as I was looking for more out of the stock system.