Car Stereos: powered sub connected but bo sound, infinity kappa, rca cables

Question
Hi! I have a kenwood excelon xxv-05v as head unit, with infinity kappa 6.5" front speakers and stock 6x9 rear speakers connected to my dual xpa4100 amplifier, and a lanzar vector vctbs8 slim powered subwoofer underneath the driver's seat connected to my head unit's hideaway receiver's subwoofer output... Everything's working for months then the sub just stopped working though it has the green light on while all 4 speakers are still working fine... What could the problem be? And aside from that.. I'm planning to add another sub(boxed) in the trunk... Probably 2 x 10" or 2 x 12" plus a mono amp to power my subwoofer box.. How do I connect it to my head unit since it has only 1 sub output? Thanks

Answer
Hi,

It's hard to say why your powered subwoofer isn't working; it's possible that there's a problem with the head unit's subwoofer output, the RCA cables between the hideaway module and the sub, or the cable between the module and the head unit.  You can troubleshoot by substituting another audio source.  The easiest way to do this would be to use a portable audio player of some sort, with a Y-adapter cable to convert the headphone jack into RCA plugs.  If you connect your portable audio player directly to the subwoofer, but still don't hear anything, then it's likely that your subwoofer is defective.

I suspect the addition of a double 10" or double 12" subwoofer system will make the powered subwoofer redundant.  However, if you want to keep both subs working, there are two ways to do it:

First, some amplifiers have RCA output jacks as well as inputs.  If your new mono amp has this feature, you can connect RCA cables from the head unit subwoofer output to the mono amp, then another set of cables from the mono amp to the powered sub.

Alternately, you can just use an RCA Y-adapter to split the single subwoofer output into two outputs.

Hope this helps!

Brian