Quick write up on adding aftermarket Subwoofer to Factory HK system
I figured I would post a little info to help anyone looking to add aftermarket sub to their CLA. I recently installed a Jbl amp with a boston acoustic 10 subwoofer to the factory HK system, it made a big difference in low end bass
The difficulty level of install was pretty low most of you should be able to perform this within a few hours if you have a little handyman skills.
Install tips
factory grommet in firewall, makes it easy to run power wire through from the inside out
Remote turn on can be tapped from the cigarette lighter, the console pulls up easily. (most amps have remote sensing capabilities now which you wont need a remote wire)
Perfect ground location next to factory amp.
Make sure you use an adjustable line out converter for the input signal, otherwise the sub may be too loud( the factory signal is very strong)
Amp easily mounts underneath floor board in trunk.
Signal input wires for factory subwoofer are (dual voice coil)
Hook up your two channel line out to
+Red
- Brown/ red
+Blue
-Brown/blue
These connections are made in the right side of the trunk, the inside panel comes out very easily, there are two push pins that hold the panel in place and both of the utility hooks have to come off which are a torx screw.
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The difficulty level of install was pretty low most of you should be able to perform this within a few hours if you have a little handyman skills.
Install tips
factory grommet in firewall, makes it easy to run power wire through from the inside out
Remote turn on can be tapped from the cigarette lighter, the console pulls up easily. (most amps have remote sensing capabilities now which you wont need a remote wire)
Perfect ground location next to factory amp.
Make sure you use an adjustable line out converter for the input signal, otherwise the sub may be too loud( the factory signal is very strong)
Amp easily mounts underneath floor board in trunk.
Signal input wires for factory subwoofer are (dual voice coil)
Hook up your two channel line out to
+Red
- Brown/ red
+Blue
-Brown/blue
These connections are made in the right side of the trunk, the inside panel comes out very easily, there are two push pins that hold the panel in place and both of the utility hooks have to come off which are a torx screw.
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