Some older automobiles were sold without a factory-installed audio system. However, most cars manufactured today have an AM/FM stereo receiver. You may find, however, that some of these receivers do not have the capability of CD or audiocassette playback. In this case, you may choose to replace the factory-installed stereo receiver.
How Does a Car Audio System Work?
An automobile audio system has several components. The stereo receiver is typically capable of receiving radio signals on the AM radio band (530 KHz-1620 KHz) and the FM radio band (87.9 MHz -107.9 MHz). The receiver often has an integrated media playback device, such as a CD player or audiocassette deck.
The receiver will have seven or more connections. These connections are made to at least two speakers (one "signal" connection and one "return" connection, for a total of two per speaker), one antenna connection, one power connection, and one chassis ground (or negative) connection.
An automobile audio system is usually power-rated in watts. This may come in a "total" number ("90 watts") or in a "per channel" number ("45 watts per channel"). This is a measure of how much power the stereo receiver can put out across the speakers.
Similarly, speakers are rated by how much power can be applied across the speaker component. A speaker that has a rating of 45 watts can be used in conjunction with a stereo receiver that has an output of 45 watts or less per channel.
Putting Together a Car Audio System
If you are installing an audio system in an automobile that does not already have a system, you will need the following items:
-AM/FM stereo receiver with mounting hardware (normally included in the stereo receiver box)
-Automotive antenna (unless the vehicle has an antenna already mounted)
-A roll of speaker cable (at least 12 feet)
-Electrician's pliers
-Vinyl electrical tape
-Mounting hardware (such as screws, small bolts and nuts)
-Wire splice connectors (blade-type connectors work well)
-Speakers (equal to the number of "channels" your stereo has)
-Small screwdriver
-Soldering iron and solder (if using splice connectors that are not blade-type)
Most automobiles have a "blank" (a plastic or metal dustcover) in the space where a stereo receiver would be installed. Remove the blank from the receiver space on the automobile. Connect the receiver's power and ground (or "receiver positive" and "receiver negative") wires to the vehicle electrical system. This can be done by splicing the power wire to the automobile starter power wire, or other suitable power source in the vehicle, and splicing the ground wire to either the automobile frame or a negative wire such as the negative connection to the cigarette lighter port.
Run a length of speaker cable to each speaker location (such as the door frame) from the stereo receiver space. If the automobile has "blanks" where speakers normally are installed, remove these, and run the speaker wire so that it comes out the back of the speaker installation spaces. The speaker cable should have at least 6 inches of slack at the stereo receiver end. At each end of the speaker cable, remove about ½ inch of insulation from the speaker cable, and separate the wires from each other to a length of about 4 inches.
If using blade-type connectors, crimp a "female" (receiving) connector to each wire on the speaker cable. Connect the speaker wires to the "male" (inserting) connectors on the speakers. If not, solder the speaker wires to the speakers. Install the speakers into the speaker spaces.
Crimp a male connector to each of the left-channel wires on the stereo receiver. Connect the left-channel wires to the speaker wires leading to the leftmost speaker. Insulate the connection with electrical tape. Repeat these steps for the right channel and rightmost speaker.
Using the included hardware (mounting strap, screws, bracket), install the receiver into the receiver space. When the vehicle is running, test the stereo system.
Tags: stereo receiver, speaker cable, audio system, receiver space, speaker wires, Audio System, automobile audio