Really Weird Problem

[geolemon]

Also - if your aftermarket HU was working properly, that brings us literally to only one of two things to check, truly:

1) all wires must be connected both correctly and properly.

2) the Alpine internal settings must be set correctly - consult the manual, as they are tricky and hidden in several places (I have two 7894's). From your symptoms, assuming #1 isn't the problem (and that is an assumption), then the problem IS that your internal amp is turned off, AND that your subwoofer is either high-passed, OR plugged into a non-sub RCA output.

There are no other possibilities, other than the HU being damaged (but I doubt this, as you would be much more likely to be experiencing one, but not both, of the symptoms you describe - because the internal amplifier circuitry is fully separate from the pre-amp level processing DSP).

[wang_chi7]

I did get the subs to work properly by setting the LPF on the HU itself (evidently the amp's filter sucks or is a shallow slope.)

I do have an amp laying around at my parents house that I'm going to hook up to the main speakers.

I'm pretty sure the HU's internal amp is fried after talking to the seller. He checked to see if its working by using the preamps (he didn't hook the speakers up directly to the stereo.) I told him that I'll keep it if it works with the 4 channel amp otherwise its being returned. Luckily he's a good ebayer, so its not a big headache.

[Justin from Detroit1]

Tell him the item is not working to full potential, and since you need to purcahse another product to get use of all of your speakers, you would like a partial refund.

[geolemon]

I'd hook up the amp and call it a day.

Getting a partial refund from this guy would be a nice token, but of course it depends on how much you got this thing for - if you paid less than half the original shelf price for the HU, you got a deal anyway.

I don't mean to be nonchalont about not quite getting all you thought you would out of this HU - but part of that is because HU's are ALL limited to under 22 watts per channel, simply by the fact that you can't fit a power supply inside a HU (the big toroids and capacitors you find inside real amplifiers - in other words "the reason real amps are so large" ), and therefore you end up with 12v-14v amplifier rail voltages on that little built-in HU amp.

So - if you've got an amp that's rated at just 25 watts per channel at home, you've got something that's technically more powerful than your HU channels - and likely is more powerful than that at any rate, unlike the wild, non-CEA compliant claims stamped on the face of the HU.

And chances are, you've probably got something more like a 40w or 50w per channel amp or better at home anyway - making for something of real benefit.

...all for the cost of what, a small distribution block a couple short lengths of 8 gauge power wire, and a cheap 16 foot RCA cable? I'll take it.

[elevation101]

I worked on an 02 impala yesterday. There was a factory amplifier up under the rear deck in between the 6x9's. Yours might not have it but you might wanna take a peek just to be sure.

[wang_chi7]

I worked on an 02 impala yesterday. There was a factory amplifier up under the rear deck in between the 6x9's. Yours might not have it but you might wanna take a peek just to be sure.

Mine doesn't, luckily. I checked and it doesn't have the "premium sound" feature. I thought that could have been the problem so I checked.

I did get the HU for really cheap. Its a '04 model that Crutchfield.com last listed at 350 or so (and it was probably more when released since that was their last price) and I got it for 150 shipped. I think I will try to squeeze a few bucks out of it (can't hurt and I would probably just ask for the price of a amp hookup kit.) I was eventually going to hook the amp up anyways, I just will have to do it next weekend when I go home now. I don't want to return the thing because its hard to find a HU anymore with its features (time correction, blackout mode, amp turn off- in my case mandatory :) , LPF/HPF, XM and Sirius contol able.)

[geolemon]

I've got a Sirius system, and I'd wholly endorse Sirius...

...however, I really wouldn't endorse getting a Sirius or XM tuner for your HU, because then you can only listen to Satellite radio in your car - or else are forced into purchasing a second tuner and paying a second set of monthly fees if you want to listen in the home or office.

While it might take up a little more dashboard real estate, I've got myself a car docking station in my Civic (summer car), in my Pathfinder (winter car), and a "boombox" it docks into in my home office. I'm even thinking about getting a cradle for it in my wife's car, since we take that one everywhere. Just dock it wherever you are, and you just pay one monthly fee, not three or four like I would have to otherwise.

Just something to consider if you are considering satellite radio.

[two4fifteen]

i second everything that was just said about sirius. i do the same with mine and love it. and for everyone else wandering about it, there's a two day FREE trial october 25-26 on their website. no radio required, just an internet connection.