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Installing a second Head Unit

04-12-2004, 06:59 PM
Situation- Stock CD Head Unit, Stock Speakers, and I want it to stay that way. (IE-no replacements here, because the stock stereo will blow away most people with modified stereos)

I want to use an mp3 player in my car, and the FM transmitters all suck. So I'm stuck with a cassette adapter, because I dont have a line in on my head unit, or the money to spend on an aftermarket mp3 ready head unit. So I'm going to install a second head unit for this purpose. Basically, I'll install it where the ashtray slides out. (I dont smoke, so no worries there). My problem is in the connections. How can I wire 2 head units to the same set of speakers, without frying anything? And how much work am I looking at? Will sound quality suck with 2 head units? Is there a way to hardwire the mp3 player to said stock head unit? Sorry for so many questions, I've done stereo work before, but never with 2 units.

04-12-2004, 07:27 PM
you definitely have your work cut out for you. You may be able to make a switching system, like out of relays, to switch between the outputs of the two head units

04-12-2004, 07:59 PM
Is there another route I can take? Because the factory connectors are where I will be in trouble, I'll look in my service manual to see it it identifies which wire in the connector goes where.

04-12-2004, 11:14 PM
oh man ur guna have fun

"lets go find a needle in the haystack, YEY"

04-12-2004, 11:16 PM
go get a wiring kit for your car from your nearest stereo store or electronics store that sells car audio. the wiring kit will have the color codes for all the wires then use a toggle switch to turn the power on from one head unit to the other. you can also get a stereo that has line in or aux in and wire your factory stereo in to that but either way you need to find out if your factory stereo has amps because you do not want to run a high power stereo in to amps.

04-12-2004, 11:54 PM
I don't know who's modified stereo you have been listening to. but their is not a factory system out their that will touch a system I can modify.
but different strokes for different folks.
factory has come a long way.
your best bet and easiest way is going to be the fm transmitter. or buy an after market cd player that plays mp3s and replace the stock one. once agine you need to find out if you have factory amps or not.
the cassette adapter wears out with time and it sucks too.
I did two stereos in my 94 Altima but I also changed out amps and speakers was a lot of work.

04-13-2004, 12:13 PM
droptop- I'm not saying that mine is the best, I've heard much better, but the quality of the music I hear from the local punks stereos blows big time.

actually, I've come up with a genious idea, I have 2 factory head units, one cd unit, and one cassette unit. I'll go to a junkyard and get a new harness, and use those connectors that connect into an existing wire, and allow you to add a new one.

04-13-2004, 08:56 PM
you still listening to cassettes?
if not I would just put the cd player in.
make sure that cd player will play mp3s and burnt cds before you go through the trouble of tearing your dash apart.
ya I know what your saying nothing sounds worse than a distorted rattling untuned and unmatched system.
I just could not resist taking a stab at your commit though.
good luck and let us know how it goes.

04-13-2004, 09:53 PM
droptop- I put the CD unit in about a week after I got the car. And the taking the dash out? I've done it in my car in under 9 minutes. (yes, I timed myself) I want the cassette unit as well, so I can use the cassette adapter to run the mp3 player. I'll get in a wreck if I have to keep fiddling with all my CD's!

On the subject of FM transmiters- I bought the Belkin Tunecast II Fm Transmitter, and put it all together. I tried to play Nelly- #1 on it, and it sounded horrible to me, no bass. I popped in the CD that had the same mp3 on it, and I felt the bass vibrate my seat, like usual. I swapped out the CD for my old cassette unit, and used a cassette adapter, and the bass was more prominent, but not the CD quality.

04-14-2004, 10:21 AM
Get a MP3 player with an AUX in and it will be easy intall, run RCAs from the cassette to the MP3 and when u wanna listen to cassettes, you can put the MP3 player on AUX input... ;) thats what I did and it takes no time and virtually no effort.

04-14-2004, 03:09 PM
I have a CD unit in now, and I want to keep it in. I wanted to add the cassette player, for the mp3 player.

Unless you guys can reccommend a better FM transmitter, the belkin one sucked.

04-14-2004, 03:11 PM

Found after a brief search

04-16-2004, 09:13 PM
you have a factory CD player in there right now ? If it's an aftermarket with RCA's ........ you can get an audio control four.1 eq/preamp, it has an aux input that is switchable from the front panel.

The FM transmitters suck because if I remember correctly, FM freq resp is is 50Hz - 15KHz

04-16-2004, 10:48 PM
Factory CD player

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