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OrangeShadow
05-25-2006, 10:03 AM
well my older brother has a couple sets of subs(either 10 or 12s i dont recall which)

my question is, is it possible to hook them up in my car if i have an aftermarket CD changer instead of a cd deck?

DBroncos4life
05-25-2006, 10:03 AM
yes, you need a FM modulator (sp)

Err maybe its something else but you can do it.

OrangeShadow
05-25-2006, 10:06 AM
cool thanks DB

DBroncos4life
05-25-2006, 10:09 AM
you would almost be better off going to WallyWorld and picking up a cheap Sony deck though. I would think it would save you time and a headache in the long run.

OrangeShadow
05-25-2006, 10:22 AM
i bought my 12 disc changer for as much as a deck would of run me. id rather have a 12 disc changer.

DBroncos4life
05-25-2006, 10:25 AM
Preparing for the Installation

Steps:
1. Gather the following tools: knife or wire cutters, solder and solder gun, crimps, stripper, screwdriver, screws.

2. Plan the installation. Know where you intend to put all the components. For example, the radio is commonly put in the factory opening in the dash, the speakers are put in the factory openings in the front doors, and the rear speakers are put in the factory openings on the rear deck. The equalizer goes in the factory opening below the radio in the dash. An amplifier with built-in electronic crossover usually goes in the trunk. The car's battery, which powers the system, is commonly under the hood, usually on the passenger's side of the car.


Routing Power, Ground and Signal Wires

Steps:
1. Route the power cable from the battery through the passenger side of the car to the amplifier in the trunk. This will prove easiest because the battery is commonly on the passenger's side of the car. You will have to feed the power cable through a rubber grommet on the firewall.

2. Route the signal cables (RCA cables) on the driver's side of the car from the head unit to the amplifier.

3. Ground the amplifier to a clean metal surface on the car's chassis. The ground should be no more than 18 inches from the amplifier. The ground cable must be the same gauge size as the power cable being used.


Tips:
You don't want to route signal wire next to power wire because that could result in noise entering the sound system. If power cable and signal cable must cross, cross them perpendicularly.

The gauge of the power cable is determined by the specifications of the amplifier you are using. The owner's manual that comes with the amplifier will probably tell you what gauge cable to use. If it does not, consult with a tech advisor from the manufacturer of the amplifier to find out.

Use well-shielded RCA cable. This will help prevent noise from entering the sound system.


Wiring the Radio and Connecting Components

Steps:
1. Connect the radio to a constant 12-volt source, an ignition lead, the amplifier turn-on and the antenna. On newer cars, the constant 12-volt and the ignition wire connections can be made through the factory wire harness. On older cars, the fuse block can serve as the constant 12-volt source.

2. Ground the radio to the chassis.

3. Connect the antenna to the proper antenna input on the radio.

4. Connect the radio to the amplifier so when you turn on the radio, you are also turning on the amplifier. Most radios have a power antenna output. This is a 12-volt line that runs the power antenna. When the radio is turned on, the power antenna goes up; when the radio is turned off, the power antenna goes down. Use the power antenna lead to also turn on the amplifier. Use a relay to make the connection, so that the line can run both the power antenna and the amplifier turn-on. Ask a neighborhood car audio retail dealer how to connect the relay. Some radios have a separate power antenna output and a separate amplifier output. If this is the case with your radio, use the amplifier output to turn on the amplifier.

5. Begin connecting components using 18-gauge or 16-gauge wire on the speakers. The wires run from each speaker to the amplifier. The longer the run, the more resistance on the wire. The larger the gauge size of the wire, the less resistance.

6. Run the speaker wire on the same side of the car as the signal wire.

7. Connect the speakers in either a parallel or series configuration. A parallel connection is when you connect each speaker's positives together and each speaker's negatives together. A series hook-up is when you connect one speaker's negative to the second speaker's positive.

8. After connecting the speakers together, run the wires to the amplifier and connect the positive wires to the positive inputs of the amplifier and the negative wires to the negative inputs of the amplifier.


Tips:
When wiring speakers together and to the amplifier, you need to consider the impedance, or ohms, rating of the speakers as well as the ohms load of the amplifier. Amplifiers are constructed to "see" a certain ohms load. If the load the amplifier sees falls below what it is capable of handling, the amplifier will shut off. Speakers come with various ohms ratings. When speakers are connected together, the ohms rating, or impedance, of the group of speakers that are wired together changes and affects the ohms load of the amplifier. If you wire two 4-ohm speakers together in a series hook-up, you are producing an ohms load of 8 ohms. If you wire two 8-ohm speakers in parallel, you are creating an ohms load of 4 ohms (8 ohms x 8 ohms divided by 8 ohms + 8 ohms = a 4 ohms load on the amplifier). If you connect two 8-ohm subwoofers in a parallel hook-up to an amplifier that is bridged mono, the amplifier will see half of the load because it is bridged. So it will be seeing a 2 ohms load.

Before you do a parallel hook-up on an amplifier, make sure that the amp can take the ohms load that will result. Find out what ohms load the amplifier is stable at and then choose speakers with the appropriate ohms rating, so that the hook-up will ensure that the ohms load is within the capability of the amplifier.

Generally speaking, most midrange, midbass and tweeters you use will be 4-ohm rated. Most subwoofers you use will be 4- or 8-ohm rated.

If you are using passive crossovers with the component speakers in the front and rear of the car, hooking up these crossovers can also affect the ohms load seen by the amplifier. Hooking up the passive crossovers' positive and negative properly can be a concern. Follow the speaker manufacturer's instructions carefully.

If you are preparing to hook up wires to the amplifier and you are not sure which is negative and which is positive, take a 9-volt battery and tap the speaker wire to the positive terminal of the battery. If the speaker first moves forward (or out), then you have touched the positive lead of the speaker to the positive terminal of the battery, and the remaining wire is negative. If the speaker's first move is backward (or in), you have touched the negative wire of the speaker to the positive terminal of the battery.




Your factory deck should have everything you need to hook up a system but the RCA plug in. Thats what you need to get. Its possible that yours has one though. Every deck I've worked with has been on a older car so I couldn't tell you if they've changed that.

Raider Bill
05-25-2006, 12:08 PM
You need some sort of crossover if you want to only have bass frequencies coming from the subs.