Factory Amp & Sub With Aftermarket Radio (DMH-2660NEX)

[Gilly11277]

Hi Everyone,

I got my factory sub woofer replaced with this and it sounds fantastic. The other night I was playing around with sound on my factory radio and noticed that the sub appears to be tied into the other four speakers (or maybe just rear?). When I increase the bass level on the radio I noticed the rear speakers get distorted at higher volumes whereas the fronts don't seem to be impacted much if at all. This tells me there is likely no high pass filter on the four speakers and the sub works like a mediocre full range speaker. I called the folks at Crutchfield and they told me my suspicion was correct and that there wasn't much you could do with the factory radio to get excess base out of the front and rear speakers.

My new radio arrived today and I thought that I could use the HP/LP filters but then realized it might not work the way I want because the sub would get lumped into the filtering of the other speakers because it's somehow tied into them. Has anyone on here found a way to use RCA jacks with the factory amp? I know this would require some modification on the amp-side by converting the RCA cables back to speaker wire so the factory amp can make use of the signals. I'm just thinking it wouldn't be that hard to do and I'd get full control of the sub. Being able to isolate the sub from the other speakers would be a huge benefit and would still be cheaper than buying a dedicated sub/amp. I'm really happy with the performance of the aforementioned sub and would rather not drop another $300 if I didn't have to.

Any help would be appreciated. Hope y'all have a good Thanksgiving!

 

[pagrey]

The factory sub does have a crossover in the amplifier, it isn't full range. You need to supply all four front channels to the amp, it only has high range inputs. If you want to reduce bass to the front or rear speakers you can't easily do it at the deck because the amp needs the signal but it's easy to add passive filters at the speakers, that's what I did. You might have to buy a few to play around with the frequencies. I used 330uF 50V capacitors on my front speakers and it's fine for my taste, I'm sure there are other ways to do it. The factory front speakers have built in filters. You could do a similar thing if you are having problems with your rear speakers.

 

[jjkenley]

Gilly - Circling back to this thread, did you connect your head unit sub preamp to you factory amp wiring?