Some include crimp connectors. You have two options when dealing with factory wiring.

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How to run speaker wire in car. Crimp connectors are reliable and easier to use too. Wiring 2 way and 3 way speakers. Connect the amplifier turn on wire the next step is pulling the radio out see our related article on car audio installation 101 and locating the amplifier turn on wire leading from it typically its blue in color. When you run the speaker wire be sure to tuck the wiring underneath the floorboards and mats for a clean installation. Simply press down on the clip insert the speaker wire and release. First make sure that the open area in the center of the rubber grommet has enough space for the power wire to pass through.
The spring loaded mechanism holds the wire in place. Spring clip terminals accept bare wire or pin connectors. Another and much more convenient way to send the powered signal from the amp to your speakers is to run the speaker wires to the harness thats behind your receiver where all your cars speaker connections are accessible in one place. Then reinstall the factory grommet and run your wire through the opening you created into the car. Standard factory made wiring is nearly always color coded. Either buy a harness to convert the factory plug to fit properly to your new speakers or remove the factory plug by cutting it out and attach the terminal ends of the wires directly to the speaker.
Run each length of speaker wire to the location designated for each speaker. Then match the colored wires of your radio and your car and twist the wires together. You cut each speaker wire from the receivers harness and reconnect it to a speaker wire coming from the amp. Next remove the grommet from the firewall and cut an opening large enough for the power wire to pass through. Blue crimp or butt connectors right work well for splicing the ends of speaker wire. Typically there are two speaker locations in the rear of the car and two in the front of the car.
Spring clip terminals can accept bare wire and pin connectors but not spade connectors banana plugs or dual banana plugs. If your car requires an output converter connect this as well so your radio will work with your car. Amplifier turn on wires automatically cue the amp to power up once the radio is turned on. To wire a car stereo start by disconnecting your car battery to avoid electrocuting yourself. 2 way speakers such as home stereo or car audio component speakers are those which come as a pre designed speaker set and use a crossover. So the most important thing here to remember is to wire speakers consistently the same way as each other.
Its a simple as stripping the speaker wire twisting the wire strands tightly then inserting them into the connector and then crimping it tightly on each end.