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As topic says, i am just trying to get the sub going in my car. I already have a four chanel amp powering the front and the back splits sitting in there, and what i was thinking of doing for the time being, is disconnecting the rear splits from the amp, and just running them off my head deck, and powering the sub from there. The questions i have are:

1. How would i go about plugging and wiring the sub up? I already have all the leads for the amp and the splits coming in. i was just going to connect the rears directly to the spilts, but then how would i connect the imput? if i have to bring in a whole new lead from the car, i am better off purchasing another amp and having that power the sub.

2. If i was able to hook it up, would i have to purchase some sort of filter, so the high frequencies don't go through the sub? It's a boxed kicker 10 inch, and am not sure whether they come with filters built in...

3. Anything else I may have missed

Cheers

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why dont you take all your speakers off the amp , and connect them to the head deck . and only run the sub off the amp . you will find it sounds much more clearer. and your bass will be more defined and clear.

i had the same situation when i made my sub . i found it didnt sound good together and the bass in the speakers were over powering the bass in the sub.

I am trying to hold of on that at the moment, because I think that will probably require me to rip the interior apart to get all the wiring together, because at the moment, all the wires, for both the fronts and the backs, come to the boot for the amp, and then they go to the speakers in the front and back. Just trying to see whether I can have the sub running without having to install any extra wiring. If not, I will have a look at other cost effective options...

Any suggestions appreciated.

Cheers

My splits don't run too well of the head unit, they needed an amp to give them lots of power - It wasnt a small deck either, Pioneer 4x45W. Not sure if you'll have the same prob running your splits off your deck?

I had a 4ch amp, and ran front splits off 2 channels, and the other 2 channels bridged for the sub. Worked Well!!

Does your amplifier have a frequency filter on it? Most do, you can flick it to Low Pass to only allow bass signals to be sent to the sub.

why dont you take all your speakers off the amp , and connect them to the head deck . and only run the sub off the amp . you will find it sounds much more clearer. and your bass will be more defined and clear.

i had the same situation when i made my sub . i found it didnt sound good together and the bass in the speakers were over powering the bass in the sub.

Sky - do you mean bridge all 4 channels to run one sub? Dont think that would work...

yeah, has a switch on there that i am guessing must be low and high frequency filter. Now i am still unsure whether i can use the cables that are coming from the head deck to the boot for the rear speakers to plug both into the sub and the rear speakers. or will i have to run a separate cable in just for the sub.

Also, whilst in a stereo shop getting a quote, the guy told me that skyline alternators are pretty basic, and that they would struggle if they have two amps running of them. Any truth to this? all i would be powering is two pairs of splits and a ten inch kicker.

To fix the small alternator problem get a big Optima battery they kick ass. I had one for a few weeks until my brother "borrowed it", it solved all my electrical problems with power drain.

I would recommend that you run 1 amp for the splits and 1 for the sub as splits really need more power then a stock head unit can provide. You will only need a few hundred watts to power a 10" kicker and that would be fairly cheap, just make sure that the amp has a low pass filter or depending on your head deck it may have a low pass corssover built into it.

yeah, has a switch on there that i am guessing must be low and high frequency filter. Now i am still unsure whether i can use the cables that are coming from the head deck to the boot for the rear speakers to plug both into the sub and the rear speakers. or will i have to run a separate cable in just for the sub.

Also, whilst in a stereo shop getting a quote, the guy told me that skyline alternators are pretty basic, and that they would struggle if they have two amps running of them. Any truth to this? all i would be powering is two pairs of splits and a ten inch kicker.

The amp switch should have markings on it to show what its for? If its a low-pass / high-pass filter, you may also have an adjustment screw to set the cut-off frequency.

You could use the speaker cables running from the front of the car to the rear of the car for your rear-speakers - these wouldn't be used for anything now? If you've got money to spend, you could install new high-quality cable, but i wouldnt bother - if you end up getting another amp, the speaker cable wont be used.

the next question is, how do you bridge a sub? It's been nearly ten years since high school physics, and i can't remember the difference between parallel and bridged. Is bridged if i plug the wire from the positive out on one chanel to positive in on the sub, and the plug negative on the sub onto negative on the amp on the other chanel. or is am completely off?

the next question is, how do you bridge a sub? It's been nearly ten years since high school physics, and i can't remember the difference between parallel and bridged. Is bridged if i plug the wire from the positive out on one chanel to positive in on the sub, and the plug negative on the sub onto negative on the amp on the other chanel. or is am completely off?

If you want to bridge your sub to 2 channels just say rear left and rear right for instance, you put the positives together and negatives together. So coming from the sub box you'll have a + and -, on the amp you'll have like + - and + - for each speaker, you put the sub negative to both the negatives on the amp and the sub positive to both positives on the amp. Easier done than said lol

But once you get the hang of it, its pretty simple. Also to add with the clarity of speakers, theres nothing better than having your speakers running through an amp, it comes down to the tune just like a car. If its not tuned properly it'll sound shit. If your cars not tuned properly it'll run shit lol

Might do that temporarily. Just not worry about the rear splits for a little while and have the sub and the fronts. don't have the time to rip the car apart to put more speaker cable through yet.

thanks for that

I had a 4ch amp, and ran front splits off 2 channels, and the other 2 channels bridged for the sub. Worked Well!!

yup same set up as mine...

2 channels bridged to run then sub, the other 2 each runs the 2 splits

the deck 50x4 or 45x4 runs the rears

so u only need 1 amp

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