Hi Guys. I've cabled up my new amplifier (4ch x 70w), run all the cables (don't you love that Nissan put a channel down the sill just perfect for that!) For all those who have done their own Amplifier install, the incredibly thick power lead - how'd you get it to the battery? The firewall doesn't seem to have a plethora of choices.... Also, maybe it's just my amp, but maybe someone can steer me straight. It's picking up noise from the engine, and also from the carputer. Any help appreciated. Amp is supposed to have noise cancelling circuitry.... Thanks Guys! Simon.
or try shielded rca leads earth them at the earth terminal on the amplifier. Should stop any induced disturbance. As for the amp wiring, remove the passenger side wheel arch, shoud be a hole in the inner guard that leads straight to the battery. Will also see a rubber bung, think about 30mm in diameter just in front of the door hinging point. Will lead directly to the interior of the car.
lol, i rember doing mine. You can make it to the battery,, you just gotta go down the side of your passanger side, through the back where you put your feet (mine had a board i had to remove) then up into the centre console, then I shuved mine through that big tube thing that holds all the wires... you will need to build a miniture robot to do all this becouse your hand doesnt fit...
i ran my poer cable down into the front guard through the big hole near the battery you pull the cable as you can see it when you open the door then i ran it through the rubber crossover where the speaker wires go to the passenger door than under the carpet and came out up near the quarter window
Cheap amps will inevitably have bad noise issues (it's the alternator whine). Even decent amps can succumb if the wiring conditions are bad. Best things to do are like aazn said, run power cable down the left and audio cables down the right. Make the ground cable as short as possible and make it a solid ground connection, no paint/rust in the way. If you still have whining issues, I use a Ground Loop Isolator. Its best to get one that matches the gauge of your power cable, otherwise theres no point running 4 or 8 gauge from the battery only to have a 24 gauge ground loop isolator..... Another method I use is an inline RCA audio filter - 1 for front, 1 for rear. That eliminated the noise from my Carputer (EEE). Then I installed a 5.1 USB sound card which didnt ground itself to the PC until it powered on, so there while always a whining noise until I switched on the carputer. After I used all these in conjunction - no more alternator whine ....but that's my fault for buy cheap ebay junk....
yer i spose ay. mine was taken out of a 89 Lazer, so i had to use what i had, fits by like,, 20cm lol..... somehow :s
Update... OK, After more fiddling, here's the state of play.... Ran a separate power lead (outside car) - Still noise (maybe a little better?) Ran separate RCA leads (over seats) - Still noise (about the same?) Disconnect RCA leads @ dash - No noise. Run separate leads from carputer to RCA leads to amp - Still noise Run old stereo to AMP - Minor noise Run Carputer through old stereo to amp - Much less noise. Car off - Carputer connected - Noise from Computer Car off - Carputer connected but disconnect power (it's a notebook) - Hardly any noise. Haven't run the power cable through properly yet until I figure this out. Currently runs to passenger's footwell, then out door to battery. (Doors open & Bonnet up in garage) So.... Don't think it's the power / wiring path so much. New amp introduces very minor noise over old head unit without amp. Old head unit must have had pretty good noise supression (Sony) New amp doesn't have fantastic noise suppression Carputer must have a 'dirty' sound signal, especially power supply. Carputer is Dell Notebook with Dell's travel power supply and 12v connection. BTW - I bought an Amp wiring kit, so it came with all the cable etc required, including that way-thick power cable and massive fuse.
The audio chipsets in notebooks are not shielded very well, and you can't earth them directly without rediculous modding and wires where u dont need. Sounds like the inline RCA filters are the way to go. Here's the one I use - cheap chinese ebay junk but it works
