subwoofer wiring

[92 SVX]

Originally Posted by Gamesy

ya i do i'm talking about the REM/signal cable to turn it on, the power and ground are in and normally i'd just hook the REM cable to the deck i dont wanna mess with the the wiring back there.

I just want to have another alternative to using the deck

Ok just wanted to be sure we were on the same page, I have never had any trouble wiring the remote wire into any 10amp or more fuse. I believe it could even be wired into a 5amp slot never tried it though.
Unless, and this could be possible, your amp has a short inside?

[Gamesy]

the amp's worked b4 in my other suby. i'm wondering if the rem cable draws current thinking that it needs a resistor or something...
anywho i gotta get a new power cable fuse. i dunno how i blew a 60A fuse :S

[Trevor]

Gamesy, you have taken no notice of my previous post and appear to be completely lost regarding what you are about. With due respect, the following may assist you. ---

Here is something I wrote for the network some years back. ---

The information which follows, although not scientifically exact, is a way of understanding much of that applicable to electricity. This can be useful to the handyman, but those with technical knowledge should pass it by.

In simple terms think of electricity as fluid/water, a conductor/wire as a pipe and a circuit in the form of a circulating pump and power source, outlet positive, return negative, pushing water around and back.

Pressure expressed as volts.

Current expressed as Amps, i.e. volume of flow.

Power as watts. i.e. a combination of pressure and volume. Amps X Volts = Watts.

Resistance, expressed in ohms, = A thin pipe, a small hole, filter, or whatever, restricting flow in the circuit.

Insulation, = What amounts to infinite resistance but which can be penetrated by means of extra high pressure/volts.

A switch, = An on/off tap/cock.

A variable resistance or potentiometer, = A tap/valve with a variable adjustble flow throughput.

A diode or half wave rectifier = A one way/non return valve.

Direct Current, D.C. Flows in only one direction.

Alternating current. A pulsating flow backwards and forwards and at a frequency expressed in cycles per second.

Transformer. When alternating current is present, enables voltage or sometimes current, to be changed/transformed, by means of separate wound circuits (windings) on a common magnetic core.

It is not difficult to appreciate how power/pressure can be lost within a circuit. These losses are referred to as voltage drop.

A thin/small wire/pipe and low voltage/pressure means maximum losses. A large/thick pipe/wire and high pressure/voltage, minimum losses. The associated significance in respect of the length and the material make up of the pipe/wire/conductor will be obvious.

Therefore in the case of automotive circuits operating at a comparatively low 12/14 volts/pressure, a very thick wire is required to power the starter motor, medium for headlights and still thinner will suffice for indicator lights etc.

It will be apparent that Engine block/chassis/body, of large volume, no matter the metal, is a better conductor than copper wire of limited cross section. Therefore for good reason, this available structure is utilised as a common ground circuit.

Contact resistance is most dependant on both area and in particular pressure. Lack of one requires more of the other. Low voltage calls for low resistance and efficient contact.

I repeat the above is to be understood as practically basic and simplistic, rather than scientifically correct in detail.

[Gamesy]

Thanks for the info trevor. now for the good news/badnews.
Bad news: for some stupid reason the tape deck stopped working and the fuse is fine. so something internal must've kicked the bucket, its still getting power cause it will eject the tape deck adapter.

Good news, that means i'm forced to get an after market deck so that the whole signal cable issue will be solved by that.

[redlightningsvx]

Definatley get a reverse plug from svxdc. They're a life saver.

[SVXdc]

Originally Posted by redlightningsvx

Definatley get a reverse plug from svxdc. They're a life saver.

Or even a "forward" harness (the kind you normally need to install an aftermarket radio)

Originally Posted by Gamesy

whats an alternate way to wire the REM cable aside from using the ignition switch?

If your amp is in the trunk, you could use the cell phone power harness. See this post.

The +12V Accessory pin would be fine for your amp remote turn-on. The B+ pin won't be adequate for the main power for an amp.

[Gamesy]

so you have a complete conversion from one to another without having to connect cables?

on a 2nd note, the deck started working again....magically

Originally Posted by SVXdc

Or even a "forward" harness (the kind you normally need to install an aftermarket radio)


If your amp is in the trunk, you could use the cell phone power harness. See this post.

The +12V Accessory pin would be fine for your amp remote turn-on. The B+ pin won't be adequate for the main power for an amp.

[SVXdc]

Originally Posted by Gamesy

so you have a complete conversion from one to another without having to connect cables?

You mean like this?

(except with the SVX 20-pin connectors)

I can build one just about any way you want.

But if all you want to do is tap the rear speaker outputs to send to your LOC (and then to your sub amp), that's much easier to do in the trunk at the rear speakers.

[SVXdc]

Originally Posted by Trevor

It would appear that you have to source a mono signal from stereo speaker outputs, as no other means is available.

Many amps today can take two inputs (left and right) and sum them into a mono signal for a subwoofer speaker.

Many amps also have a built-in Line Out Converter (LOC) to take speaker-level inputs. For those that don't, people use an external 2- or 4-channel LOC.

Some LOCs, such as several from davidnavone.com, even have an integrated amp trigger (detects sound on the inputs and generates a 12V remote turn-on signal for the amp).

[Gamesy]

i was just referring to if i get an aftermarket deck so ya one end plugs into the stock harness and the other end plugs into an aftermarket deck. like a pioneer avic.

i have an LOC already hooked up i just need to run a signal (REM) cable to turn on the amp. were you saying to wire it to the cellphone plug?
would turning on the car just send power to that plug?

[SVXdc]

Originally Posted by Gamesy

i was just referring to if i get an aftermarket deck so ya one end plugs into the stock harness and the other end plugs into an aftermarket deck. like a pioneer avic.

Ah, I got ya. That's actually not a bad idea for the SVX -- it would save you from needing to crimp or solder two harnesses together, and would reduce the "bulk" behind the HU (where space is cramped).

I haven't made those before, mainly because I don't stock the countless HU harnesses. But if somebody really wanted that, I could. You'd either need to send me your HU harness for me to put an SVX "forward" connector onto the bare wires, or I'd need to buy a replacement HU harness and do the same.

i have an LOC already hooked up i just need to run a signal (REM) cable to turn on the amp. were you saying to wire it to the cellphone plug?
would turning on the car just send power to that plug?

Yes and yes (turning the key to either "Accessory" or "On," if you use pin 4).

[92 SVX]

Originally Posted by SVXdc

Ah, I got ya. That's actually not a bad idea for the SVX -- it would save you from needing to crimp or solder two harnesses together, and would reduce the "bulk" behind the HU (where space is cramped).

I haven't made those before, mainly because I don't stock the countless HU harnesses. But if somebody really wanted that, I could. You'd either need to send me your HU harness for me to put an SVX "forward" connector onto the bare wires, or I'd need to buy a replacement HU harness and do the same.


Yes and yes (turning the key to either "Accessory" or "On," if you use pin 4).

How much do you think that might cost, I am looking to buy a double din unit possibly with nav and to reduce the bulk of wiring might be a great idea. I would of course need to send the HU plug.

[Gamesy]

Originally Posted by SVXdc

Yes and yes (turning the key to either "Accessory" or "On," if you use pin 4).

Wow that seems alot simpler!, btw what is that whole cellphone thing all about? is it for those old school car phones?

[SVXdc]

Originally Posted by 92 SVX

How much do you think that might cost, I am looking to buy a double din unit possibly with nav and to reduce the bulk of wiring might be a great idea. I would of course need to send the HU plug.

It would depend on the HU's harness, but in general it would be a little more than the price of a plain SVX "forward" harness.

For example, Clarion likes to have two Yellow wires on their harnesses -- a low-current one only for the radio's memory, and a higher-current one that provides main power. I would need to solder them together, with a single wire going into the SVX harness (only one 16 or 18 gauge wire will fit in the SVX contact pins I'm using).

Some HUs don't have a wire for either a motor antenna or amp remote on. That would require Y-ing the HU's +12V Accessory wire into the SVX's power antenna pin.

And you might want to do something custom so that the SVX's BRIGHT button (dimmer cancellation) works with the HU.

When you get a new HU, contact me by e-mail to work out the details.

Originally Posted by Gamesy

btw what is that whole cellphone thing all about? is it for those old school car phones?

Yes. See the thread I linked to.

[Gamesy]

It Works!!!