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Discussion Starter #1
New rear sub woofer and amplifier addition to stock Head unit

I have a 2000 hse 4.6 with the stock headset. The previous owner removed the rear subwoofer enclosure and simply cut the wires to what i assume went to the sub and amp. All i have showing is 5 wires ..1 gray/blk 2 orange (1 solid and 1 striped). 1 purple and 1 solid blk.

I have purchased a small 10 inch sub and a 400wt 2 channel amp. Since the stock head unit has no RCA out in the rear..I was wondering how to get the signal wires to my amp. I currently have my amp powered by clamping the amp blue power wire onto the gry/blk wire from the stock wires that plug into head unit. Not sure if that is correct as there are 2...

I understand that the orange wires in the back that were cut go to the pos and neg of the subwoofer...I am just having trouble bridging the 2....please help...
 

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Re: New rear sub woofer and amplifier addition to stock Head unit

Looking at the diagram it seems the purple is power to the subwoofer amp, the black is ground for the amp, the orange and orange/black are the signal (left and right channels) wires to the sub amp and the grey/black is the signal ground. So you should be able to connect them to your replacement amp and then connect your sub(s) to the amp output.

However, one thing to be aware of is that the purple is permanently powered so I presume the original amp turns itself on when it detects a signal on the inputs so you may need to fit a relay so it is ignition switched or you will flatten your battery when the car is left. Not sure about in the US but over here eBay UK usually has a few original sub units going for around £40-50.
 

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Re: New rear sub woofer and amplifier addition to stock Head unit

Heya!

I am no expert, and i do not mean to step on Gilberts toes, but it seems to me the wires play out like this. (Rave and general stereo setup know how)

Purple: Fused 12v (20 Amps, fuse 15 at BeCM)
Black: Ground
Orange/Black: Signal-
Orange: Signal+
Grey/Black: Amplifier turn on from HU.

I am not sure i have the orange ones the right way 'round, if your new sub either lights up PROTECT or sounds like crap, (Out of phase with the rest of the speakers) then switch the orange and orange/black.

As far as line level to RCA, some midline-high line amps have a little white connector with an included pigtail for high level inputs. However i'm wondering if since the output is designed for a sub anyway, if the stock head unit outputs sub level already.

-Angel
 

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Re: New rear sub woofer and amplifier addition to stock Head unit

The outputs are all balanced, each driven from a pair of opamps. If your aftermarket sub has a phono input, you probably just one one of those wires and ground.

I think you'd be easier picking a sub and its mating connector up from a scrappy...
 

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Re: New rear sub woofer and amplifier addition to stock Head unit

The grey/black was the one that had me confused as it comes out of the head unit and splits to multiple places which the diagram shows as Radio but it has come from the radio in the first place, so I had to make an assumption on that one. If it were me, I'd just pick up an OE sub from a scrapper. It fits neatly out of the way so no boot space is lost. In fact, having heard the one in Gordon's car, I may just do that once I've finished on the engine but suspect I'll have to run the cables in (from the line out on my aftermarket head unit) as mine was never fitted with one in the first place.
 

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Discussion Starter #6
Re: New rear sub woofer and amplifier addition to stock Head unit

ok ..well this is what i did based on my understanding of ur collective suggestions and explanations... I simply folded and wrapped the purple wire with electrical tape so it would arc..cause i dont need it. The blk/gry wire i clamped the blue remote lead wire from the amp to it ..but i did this behind the head unit. so i folded and taped the blk/gry wire at this end because i didnt know what else to do with it. the 2 orange wires i converted to rca plugs so i could plug them into my amp..left and right side input...and the remaining blk wire i simply grounded to frame...
This was my result...when i re connected the battery and turned the key to the on position...the headset and amp turned on...and i could hear my new sub..but very damped sounding...I removed one of the rca plugs from the amp while stereo was playing and the sub came alive...i replaced the rca plug....damp sound again...this vast sound difference from the sub would happen regardless of which rca plug a pulled...In otherwords...the sub sounds awesome with either rca plugged in...but sounds completely muffled when both rca plugs are in...please help!!
 

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Re: New rear sub woofer and amplifier addition to stock Head unit

Try using the orange/black as a signal ground. Leave the orange connected but ground the orange/black and see what happens.
 

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Re: New rear sub woofer and amplifier addition to stock Head unit

The orange wires aren't left and right. They are a balanced audio output. One goes positive while the other goes negative.

There is no left and right for the sub.

Just use a single input with one of the orange or orange and black wires, leave the other floating (really a resistor to earth would be better) and wire the outer of the phono plug to the earth lead in the loom.
 

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Re: New rear sub woofer and amplifier addition to stock Head unit

If you aren't using the purple wire to power the subwoofer, then where is the main power feed coming from?

The grey/black wire - as mentioned already is just a remote 'turn on' wire - and isn't designed to actually power anything.
 

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Discussion Starter #10
Re: New rear sub woofer and amplifier addition to stock Head unit

my sub is connected to my amp which is powered from my battery..I hooked up the amp as instructed in the amp manual.. brown wire from amp is ground..red wire from amp goes to battery(fused)and blue wire from amp i have clamped on blk/gry to turn it on...when stereo is turned on...if i used purple wire for same purpose it would be on all the time..cause the purple is constant..12v
 

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Re: New rear sub woofer and amplifier addition to stock Head unit

Why run in an extra wire to the battery when you already have a fused supply there on the purple wire? Just connect the red wire from your amp to the purple, it will still only turn on when the signal from the blk/grey tells it to.
 

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Re: New rear sub woofer and amplifier addition to stock Head unit

As Gilbertd says....

There's no difference in running a fused wire to the battery which is live all the time, and the Purple wire, which is already fused and powered all the time.

Most equipment like that is designed to have a constant 12V power source, but draw very little current (a few mA if anything) when in 'standby' and only woken up when there is a 12V supply on the 'remote' line (grey/black in the RR - blue as in your amp, or blue/white stripe as on my JVC head unit)
 

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Re: New rear sub woofer and amplifier addition to stock Head unit

Heya!

To Marty and Gilbert,
This is a good idea, however the purple wire is fused at 20 Amps. If his amplifier requires more (Aftermarket usually eats more than stock) then he'll just keep blowing the fuse at the BeCM. Ive always looked at the fuses on the amplifier itself and added 15% to the combined rating of the fuses for the main power wire. Overkill? Maybe. Safe? Absolutely.

To OP,
If the sub sounds good with just one RCA jack plugged in, why not just leave one jack in? My guess is the amp is looking for Stereo inputs (Not just the single channel from the headunit Orange wires) Leave the white RCA in and call it a day? As i said from my understanding you would only get one RCA out of the existing wires anyway. Tip would be orange and ring/shield would be orange/black.

-Angel
 
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