well i checked realoem, they are different. I never knew they were different mid-woofers.

 

loll mine aint got no sub at all, sound sucks, but hey it gets me through days to days so no major complaint lolll

 

I am nearly positive the logic 7 subs are different than the standard subs.

I looked into upgrading to logic 7 in terms of the sub only but BMW wanted something around 400 each for the sub...sometimes I wonder if anyone EVER buys parts from the dealership.

One upgrade you can do is to upgrade the amp. This will immediately improve the sub response. I believe Bruce has a write up on this.

As far as the quality of the standard sub, I actually do not think it is all that bad. If you upgrade the amp, the sound is pretty darn good.

Others, including myself, have upgraded the standard sub with Earthquake Sounds 8 inch SWS. I can tell you from experience that the initial upgrade sounded great, but the subs eventually blew bc they suck !

 

yea i had the earthquakes as well, i blew two pairs with an aftermarket amp. This time im thinking about running them with the logic 7 amp and getting the 2ohm version. Im not looking for serious bass, i just wanna fill in the midbass gap since i have sub in the trunk.

Or i was thinking about using the standard subs with the logic 7 system, but not sure if they will sound any good.

 

How is the sub inn the trunk by the way. Does any of that bass make it into the cab? Does your trunk rattle at all? What kind of set up did you run just amp tap into factory power then sub in the trunk?

 

i have one 13.5" jl w7 in the trunk. Yes the bass does make it into the trunk. My previous setup I had a 12 inch W3, which also had good bass. The trunk does rattle and you do hear rattles, like the rear deck sometimes. With my w3 I did not have this problem and bass was great. You just need to tap the speaker wires from the amp to LOC converter, which gives you low input RCA's. Which you connect into your amp. Its quite easy. Dont buy Earthquakes and amp them, it will not satisfy you. If you like bass then it wont, and they will blow if you use them like subwoofers. I would recommend a sub in the trunk like a W3 or W6. Btw i have my W3 with an amp for sale, so if your interested PM me.