auto leads wiring adaptors

[james08]

does anyone know which one i need? i got one off ebay the other night and it arrived this morning so i tried to fit it but it has the wrong plug to the cars wiring, i think the part number was pc2 66 4, i cant find a picture of any of the other that say will fit so i can be sure of it fitting before ordering, if anyone has any use for the one i have pm me

[james08]

ive had a thought today after finding out that i have an amplified system, if i use the wiring adaptor ive got to plug into the back of the cd player then cut off the plug that would connect to the car. use some form of connectors to connect to the cars wiring (had an idea of using the plug off an old radio), this way would only get the door speakers working and leave the ones under the rear seat not working so to power those i thought about getting an amp running a phono from the new cd player to the amp then to the speakers under the seats

anyone know of any reasons why this wouldnt work?

[XJRTwinTurbo]

hey.

i have done exactly what you are suggesting.

I have wired my front and back door speakers into 2 channels rather than 4, as on the older cars they have a common ground which is a pig to wire as 4 channels.
this is then amped up by a 240w (max) cheapo 2 channel amp fed from the front pre-out on my HU.

the rear floor speakers are wired in exactly the same wau and are amped up by an identical 240w (max) cheapo 2 chanel amp set to 'low pas' and this is fed from the rear pre-out on my HU.

This works really great and I have a brilliant sound from it.

I actualy replaced my rear door and floor speakers with halfords ripspeed ones, their newer range and they sound brilliant. the fronts i went for alpines as they have a better HF response but are still budget.

i have actually only 'loosely' fitted the amps, in that they are slung under the front seats!!

[james08]

so youve run new wires from the cd player to them or used the original wires? i was thinking of just using the standard wires, how have you done that?

[XJRTwinTurbo]

basically i have a pair of pre-out cables running from the cd-player down the drivers side of the propshaft tunnel,
i have power leads taken from the back of the headunit (the earth and remote) and the constant feed for the amps is taken from the ciggy lighter) running through the ski-slope and centre console,
then i basically ran 4x 2core cables from the amps under the seats along the prop tunnel (on the other side to the pre-outs (i hate whining radios!!) under the ski slope and connected to where the original headunit once was.

[james08]

so this is how yours is done?


i was thinking of doing this


thats use the wiring adaptor i have to power the door speakers (it only has 4 speakers on it), then use 1 of the 3 sets of pre outs the cd player has to run cable to an amp to power the speakers under the seats, then use a 2nd pre out to an amp to power a sub

click on the pics to get them to show properly

[XJRTwinTurbo]

the top drawing is exactly how ive done mine.

i am wanting to add a sub to my setup, have a couple of old ones kicking around but the firewall between the boot and passenger compartment does help matters.

on the janspeed im going to cut it out, move the tank into the boot floor and re-firewall it.

you may find that your headunit isnt powerful enought to run the 4 door speakers if you keep the common ground as you will have to run 2 speakers from one channel, unless your planning on cutting back the wires to the door and adding an extra ground for the rears.

i just didnt fancy pulling out the interior on mine to do it properly and as i had a spare amp laying around i could chuck in to power the doors i wired em together.

[james08]

head unit is about 50w x 4, would that be powerful for all 4? why would i have to add a ground to the speakers?

[XJRTwinTurbo]

The early xj40's (with the speakers in the floor) use a common ground setup, basically you have two feed wires but they share the same ground back to the headunit.

It works because the headunit goes from positive to negative on the feed and the ground stay constant.

On modern headunits you have two wires to each speaker and they have opposing voltages to each other.

Modern headunits will usually overheat and / or go pop if you tie the two grounds together.

You wanna check the manual and see if it says 'not suitable for common ground' etc on it.

So you have two solutions, pull both front and back speakers (but split left and right) together and run from one channel which I wouldn't recomend) or do exactly the same an put another amp in there for them.

[james08]

i think ill run them all off an amp then sounds easier, is it easy to get the wiring into the doors?