Introduction: Tool Box Boom Box

While at the park, sitting in the school parking lot, camping, or at the construction site, do you have to turn your car radio up loud and leave the windows open so you can make out the beat of the music? This instructable shows how I put external speakers in my truck so I can use them when outside. The speakers are in a safe, dry place, and no one expects it when you open the tool box to blast your beats.

Step 1: Parts

Probably the most important part of this project, and the first step, is to get a truck and tool box. This could be the most expensive part of this instructable, but if you already have a truck laying around you're set to go. The truck I used is a ford ranger with a highway products tool box.

the speakers easily fit in the tool box with about an inch of space on each side. Having the speaker boxes with slanted sides helps to aim the music away from the truck.

tool box
baling wire
speaker cable

wire cutters
flat and phillips screwdrivers
wiring diagram for radio

Step 2: Radio

There are several ways to wire the speakers to the radio. My radio has an equalizer with front and back speakers wired separately. When I am in the car, the balance is set to forward and only the front speakers play. To use the tool box speakers set the radio to rear balance and only the back ones play. The biggest problem with this method is if the battery dies the radio resets the balance to middle by default, and because the speakers are outside the truck, it is hard to hear that they are turned on.

Method 2 would be to wire them parallel with the other speakers and add a toggle switch to turn the rear speakers on and off. This method may work best for factory stereos, or if the radio head unit does not have wiring for rear speakers.

The radio used in this example has wiring for front and back speakers and a remote control that makes it easy to switch between songs from outside.

Taking the radio out of the car varies, but usually they have a face plate that can be pulled off (picture 2), a frame that is snapped in (picture 3), then the radio can be pulled out (picture 4). I used a flat screwdriver to pull out the radio. Check the radio installation instructions before doing this step so that you don't break the radio.

To take the face plate off, there should be an eject button. If there is no eject button, the face may be attached. The black frame should be pulled off without any tools, but if it is stuck, you can use a flat screwdriver to pry it off.

Wire the radio in step 5 after the wire is ran through the truck.

Step 3: Running the Wire

The radio is inside the truck, and the speakers are outside. To run the wire out to the speakers find a hole in the truck. In the Ford Ranger there are a few holes,a large hole under the gas pedal and smaller ones under the seat. It would have been easier to use the large hole that was close to the radio, but it is safer for the wire to be inside the truck. I ran the wire under the floor to the hole then out to the tool box.

First, find where the holes are by looking from under the truck. Remove the plastic trim on the floor to free the mats (picture 3). Then lift up the floor mats to run the wire to the holes.

Push out the plug in the floor and run the wire through it. Then run the wire under the truck and between the cab and bed to the tool box.

I ran the wires for both the left and right speaker through the same hole.

Check that the wire is long enough to reach the speakers from the radio before cutting the wire.

Step 4: Wiring the Speakers

Now that the speaker wire is run from the radio to the tool box, check that there is enough slack in the wire to open and close the box, then cut the wire. Strip the casing off the wire, then fold the wire over and twist it so it is stiff and easy to push into the speaker terminals (picture 1). The red terminal is the positive side. There should be a way to differ between the 2 wires; mine were copper and silver but sometimes they have a dashed line, be sure to remember what you used in the positive side of the speaker and do the same for the positive side in the radio.

To attach the speakers to the top of the tool box, I used baling wire, but they can be glued or screwed in. The baling wire is about the same color as the speakers and is nondestructive. I used speaker wire in the photos so it is easy to see the wire.

Start by finding 3 points that the wire can be secured to. My toolbox has a pipe running along the lid that was easy to feed the wire through, then I wrapped it around the locking clasp and where the piston attaches to the lid. It took some tweaking, but the speaker can be secured. The fourth picture shows the final speaker placement.

Step 5: Radio Wiring

The tricky part is getting the wire up to the radio. If you cant push the wire up to the radio from below the dashboard in the the first few tries, use a coat hanger. Straighten the coat hanger out, then run it from behind the radio down to the floor. Tape or tie the speaker wire to the coat hanger, then pull the coat hanger and wire out through radio hole.

Using the radio diagram, wire the speakers to the radio. Match the left tool box speaker to the left radio output and right speaker to right radio output. Be sure to use the same positive wire that you used in for the speaker. Cover the wire with electrical tape or a wire nut so that the wires are not showing.

Test the radio and speakers before putting the radio back. If everything works, proceed to step 6. If you have problems, check the radio wiring diagram, then check all the connections.

Step 6: Finishing Up

Speakers are installed and everything works. It is time to clean up.

Reverse the steps used to pull the radio out to put it back in.  Put the plug back in the hole. Lay the floor padding back down on top of the speaker wire, and screw the trim back on.

Under the car, make sure that the speaker wire is not hanging low. I used a small piece of baling wire to secure it in place.

Take the truck out and test out the speakers.

Car Audio Challenge

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Car Audio Challenge