I just put a new head unit in my Crossfire using the Scosche VW harness. I believe this harness sends the speaker-level output directly to the factory amp, which then goes to the speakers.

I'm pretty sure my aftermarket head unit is sending a much higher signal to the amp than the factory unit. This is causing me to get a lot of noise--and for the volume levels to be high, even at the lowest setting on the new head unit.

I have a few questions:

1. Where is the factory amp located in the Crossfire?

2. Is it possible or wise to disable/bypass the factory amp and just power the speakers from the head unit?

3. If, as I suspect, the factory head unit sends a low signal to the amp, and since I have RCA outs on my new head unit, can I run RCAs from the head unit and splice them into speaker wires in the harness?

Any advice is appreciated. Thanks.

 

I'm in the process of doing the same install with a Panasonic HU and Sirius direct adapter. After researching this board and Crutchfield I'm doing the install the way you described. I used the VW harness for the power connections, etc. but cut and spliced in some speaker wire -> RCA line converters to connect to the headunits front and rear pre-outs. Running the VW harness alone for the speakers will over-power the factory amp and also cause you to amplify the noise from the aftermarket HU. HTH - Jay

 

Did you complete the installation? If so, or after you do, please let me know how it worked out. I was considering bypassing the amplifier altogether. I'm not sure which method would work best.

 

Ok, from what I understand about the factory amplified system is that only the rear speakers go through the amp, and the door speakers are powered by the radio. When changing the radio, you will never get the rear speakers to sound the same unless you have a low-pass crossover in the radio for the rear speakers. The factory amp does not have it built in, it is in the radios outputs. The best thing to do in the crossfire is replace the radio, by-pass the factory amp, and replace the rear speakers wit ha set of full range speakers. You may loose a bit of bass, but you will have better clarity and volume. If you keep the factory amp, you can adjust the levels of the rear speakers going to the amp with the converther until it is at the proper levels.

 

If you bypass the amplifier...sell it to me.... mine is fried...and I NEED AND ORIGINAL AMPLIFIER...THANKS...

 

The factory head unit has two channels...LEFT and RIGHT. Both those channels are powered, and go to the factory FOUR CHANNEL amps front and rear inputs by splitting the wires into two as they travel to the amp. The amp then powers the signals further, and send them on to the front and rear speakers.

I have an aftermarket head unit with RCA FRONT LEFT and FRONT RIGHT pre-amp out's going to the factory amp. When I get the time, I will run RCA's from the REAR LEFT and REAR RIGHTS on the head unit to the rear inputs on the amp that are now being fed by front signals.

1. The factory amp is under the 45 degree sloping section of the passenger side foot area that runs up to the firewall. This is why the passenger side has less leg room than the drivers side.

2. Yes it is possible, but I think pre-amp outs to the factory amp will probably get you a better sound than the head unit's tiny amps. This is double useful if your head unit has an option of turning off its amp entirely...improves sound quality, and reduces heat on internal dash components and CD's, etc. that you stick in the head unit.

3. Yes, you can just stick an RCA connector on the + and - wires running to each factory amp input and plug those into the back of your head unit. Works beautifully and gives you a much more relaxed and noise-free sound than the stock head units powered outputs going to the factory amp.

 

The drawing showing power to the subwoofers is not correct. The Infinity amplifier is six channel not four and it powers the two dual voice coil subs, one amplifier per coil, plus the front doors with the passive crossover to the tweeters.

 

Has there been more work on interfacing aftermarket head units to systems with the amplifier and subwoofers behind the seat?

I have a 50w unit on order.. it's black vs silver.

What's the consensus, can I just plug it in or am I asking for problems?

Is it true that instead of using speaker outputs I should patch the RCA's to the outputs?

 

Your asking this from a member who has been inactive here since.......... Last Activity: 06-21-2021
And from a post he made on 07-29-2008

 

Realizing the feedback above from Valk, getting a response from RedInterior may not be coming any time soon. But to help you with your new head unit, I'm attaching the best feedback I came across for connecting an aftermarket head unit to the existing Crossfire circuitry. You need to read this & do as he did.

 

hey thanks!

 

This forum sent me an email of the activity! Don't count me out yet!

 

Welcome back Its very rare to see a member back from an old post but I'm glad some of you have email set up as you do
Did you eventually sell your Crossfire ?
Based on your location I wonder if ya ever attended this event ?
We have been going each year since 2007 - We park in Memorial Park at 13 Mile rd. and Woodward Ave.

Woodward Dream Cruise - Attendance History w / pics

 

I did not work on the Crossfire, but I did work with the six channel amplifier that is in the Crossfire. It is the same six channel amplifier hardware as the full size Dodge truck (2003 as I recall) with different equalization parameters. The amplifier input is four channel balanced. It is designed to accept speaker level signals into the DAC. The Crossfire harness Y-connects the radio speaker terminals from four wires out of the radio to eight entering the amplifier. That is the left front output pair of the radio goes to both the front and rear left input terminal pairs of the amplifier. I seem to recall only a modest amount of gain the the Crossfire parameters; just enough the amplifier input won't clip before the 6 channel amplifier does. The input circuitry in the amplifier is designed for speaker level signals as in the classic car audio "booster amp" configuration. RCA connections are unbalanced and therefore not recommended, though the amplifier may work okay with them. The amplifier balanced input circuitry is very good. Bear in mind that "line level" and "speaker level" voltages are nearly the same. The difference is speaker outputs have more current capacity. Your new aftermarket radio may have four channel speaker outputs and a front/rear fade control. Be sure you connect only the two front channels and insulate the rear output terminals (or wires). Then set the fader on the new radio to 'front'.

 

Crossfire is still here. I was at the first Woodward Cruise and every year until recently.

 

The connections shown in the attached pdf appear to connect all four speaker output pairs of the aftermarket radio to the Crossfire harness. This is incorrect and may damage the aftermarket radio sooner or later. Only two channels should be connected. For details of the correct connections see my other post on the Crossfire amplifier.

 

hey, thanks. That's exactly what I wanted to hear. So even though the new radio, and the car both have standard ISO plugs, I need to be sure and isolate the new radio rear speaker connections. So i will take a male and female pigtail and wire pin to pin except for the rears.