[Viffermike]

Originally Posted by kdog26372

Ok, so got around to installing the JL Audio C2-400x coaxes in the rear deck. Pretty straightforward installation. Take off grills using a thin plastic trim tool starting with a front corner and once that pops the rest just come off with ease. Take off 3 torx head screws using in my case a small allen like wrench individual torx. Can't use screwdriver type torx as you'll hit the back window, too tall. Then you simply use pliers to full out both clips to 4 inch speaker. The one wire will have a black grommet on it and go to the HK tweeter, tuck that one away and leave HK tweeter in place. Then plug in JL speaker using Ebay adapter using search BMW OEM Speaker Connector Harness Pigtail. It's $10 and says only 1 adapter, but there are 2 in box, so I ended up buying an extra that wasn't needed. You'll need to bend off 2 of the 4 JL tabs to mount the new speaker. I just used 2 screws and it was very secure. Easiest to do with seats folded down as headrest would be in way. 15 minutes and done if you have the tools handy.

Next is testing the sound. I have the HK system with no other mods. So just replaced the rear decks. As expected these speakers have a lower sensitivity when compared to the HK speakers up front, thus I needed to shift the fader to the rear to about the 65-70% range. Then main system volume will naturally need to be about 25% higher than you're used to get same volume level.

The sounds is substantially better. Simply put the soundstage appears to be around the front of your face rather than the front dashboard. The sounds is much more full particularly in the midrange and if I move the fader 100% to the back and turn volume 70% there's actually some base punch to be felt/heard whereas the HK were always garbage and tiny sounding. I can see how matching this with changing the fronts too would be a good combo, but I'd think the center would need to be changed or disconnected too if you went that route, maybe I'm wrong, but low sensitivity door speakers and high sensitivity center I'd think the center/worst speaker would be the dominating force up front in that setup.

All in all, a solid improvement for about $100. Side note, the HK speakers weigh next to nothing and appear to be complete garbage.

Just wait until you replace the fronts and disconnect that absolutely unnecessary center channel. "Solid" will become "surprising".