I have an Alpine CDA-9831 head unit which has 3 sets of RCA outputs (front, rear and subwoofer). The head unit also has LPF and HPF crossovers. When I enable the HPF crossover, it's active against all the RCA outputs (including the sub). The same thing goes for the LPF crossover, when activated it's active for all RCA outputs. The LPF also seems to have priority over the HPF crossover. So if they're both set, then it behaves as if only the LPF crossover is set. I'm having a hard time understanding why the crossovers would be active on all three outputs.

I would like to be able to set the crossover (HPF or LPF) to 120hz and have high and low frequencies sent to the appropriate amps, but that doesn't seem to be the case. I either get the low or high frequencies, but not both. Am I missing something here? This just doesn't make any sense to me.

BTW...I have two amps. One for the sub connected to the sub out, and one for the door speakers connected to the front output. I thought I could set the crossovers on the amps to flat, then use the crossovers on the HU to more accurately adjust the crossover point. I'm either confused or misunderstanding how to configure my equipment.

Any help would be greatly appreciated.

 

I think I may have made a mistake in my wiring. Connecting the sub pre-amp outputs to the wrong amplifier. Doh!

 

Oops, That make s abig difference. Make sure not to go to high in the Hz on the sub or the sound will become localized and you'll be able to tell where the sub is. Also turn off all the X-overs on the amps, the HU is the one to use.

 

On the 9833 HU there is a 2 way/ 3 way switch, I don't know if you have this, but it should be set to 2 way for your application.

 

I figured everything out. Yes, I did have the wrong patch cable connected to the wrong amp. Boneheaded move on my part.

I also learned that Alpine's subwoofer control is an attenuator, so that setting it at +15 delivers the full 4 volts of current to the amp. It defaults to 0, which has a huge effect on the amount of bass.

Everything's hooked up, and sounds great. Set the crossovers to 80hz, which is the most natural to me. I was never happy with the sound when using the crossovers on the amps. I never played around with them enough to get the correct settings. The crossovers and subwoofer control on the HU make things much, much easier.

The 9831 is only 2 way. Found that out when using Alpines i-Personalize.