Suitcase BoomBox

The Suitcase Boombox is a vintage suitcase converted into a boombox, complete with two subwoofers and four tweeters. The whole system is powered by two lead acid batteries hooked up to a charge controller, so the boombox can be charged via an AC/DC power supply or even a solar panel. The mini amplifier delivers 25 watts of power per channel, giving the system a lot of volume, comparable to a car audio system. You could definitely take this out to the park and start your own mini dance party or use it to play loud music in your room. What I love most about this project is that no two suitcase boomboxes will ever look the same. Depending on the type of suitcase you use and the size and configuration of your speaker setup, there is plenty of room to apply your own personal style to the project and make something truly unique.

Parts List:

(1x) Vintage Suitcase (I found mine on Etsy)
(2x) 12V/4Ah Sealed Lead Acid Battery Radioshack 55034004
(1x) Pioneer TS-D1720C 6.75" Component Speaker Package Radioshack 55032192
(1x) Pioneer TS-D1720C 5.25" Component Speaker Package Radioshack 55032190 (I ended up only using the tweeters from this package and saving the 5.25" speakers for another project. You can also replace this part with any other 4Ohm tweeter.)
(1x) Sunforce 30-Amp Digital Charge Controller Radioshack 277-110
(1x) Topping TP20-MK2 MKII TA2020 Class T-AMP Digital Stereo Amplifier Amazon
(1x) 3-Ft. 1/8" Stereo to Dual Phono (RCA) Plug Y-cable Radioshack 42-494
(1x) 1/8" Stereo In-Line Audio Jack Radioshack 274-274
(1x) 1/8" Stereo Panel-Mount Audio Jack Radioshack 274-249
(1x) 3-Ft. 1/8" Stereo Plug Cable Radioshack 42-223
(1x) 50-Ft. 16-Gauge Clear 2-Conductor Speaker Wire Radioshack 278-1267 (you will only need about 15ft)
(1x) 22 Gauge stranded wire, multiple colors Radioshack 278-1224
(1x) black electrical tape Radioshack 64-2373
(1x) Size M Panel-mount Coaxial DC Power Jack Radioshack 274-1563
(1x) AC-DC 12V 1.5A Power Supply Radioshack 273-316
(1x) M type plug Radioshack 273-344
(1x) 3/16" battery terminal connectors Radioshack 64-3132

Additional Materials/Tools:

Wire Cutters/Strippers Radioshack 64-224
Rosin Core Solder Radioshack 64-009
Soldering Iron Radioshack 55027897
Razor Blade Cutting Tool (for cutting leather suitcase)
Power Drill
Dremel
Screws (be sure to get some that match the hardware on your suitcase)
Locknuts/nylon nuts (for areas of high vibration) and regular nuts
Small L-Brackets
Screwdriver
1/4" plywood - I needed this to add some structural support to my suitcase, if you use a hard clamshell case, you may not require any additional support.
scrap wood (for mounting charge controller)
marking pen
metal file
wire crimper Radioshack 64-225

Step 1: Layout Speakers

This step will vary from suitcase to suitcase.  My suitcase was 20" wide and 11" tall, this was enough space to mount two 6.75" subwoofers and four 1.75" tweeters.  I cut out paper to help visualize the layout of the speakers on the side of the case.  Eventually I settled on a symmetric layout, with the two subs in the bottom center, and the tweeters along the upper corners.

Step 2: Clean Out Suitcase

You'll want to clear out a lot of room to mount all your components to the inside of the suitcase.  Use a razor blade to cut out any excess material (cushions, fabric dividers) and remove any extraneous hardware (clips, brackets) with a screwdriver.

Save these scraps, you might use them later in the project (I used them to make a pocket for holding my iPod).

Step 3: Cut Out Suitcase Lining

I used a blade again to cut out the lining of the suitcase, on the side where I planned on mounting my speakers.  I also cut out some warped, plastic corner pieces that were sticking up.

Step 4: Install Structural Supports (if Necessary)

The walls of my suitcase are made of leather with a fabric lining, on their own they will not be able to support the weight of 2 subs and 4 tweeters.  I cut out a piece of 1/4" plywood so that it could fit snugly against the wall of my suitcase and provide extra support.  I used a laser cutter to cut out the speaker mounting holes (pdf of cutlines attached below), these cuts could also be cut with a jigsaw or Coping saw.  I kept the tolerance of my support structure tight, so it essentially press fit up against the suitcase wall.

Step 5: Trace Cutlines on Suitcase

I used my structural support as a guide to trace cutlines onto the inside surface of the suitcase with a pen.

Step 6: Cut Holes in Suitcase Wall

Carefully cut along the traces and create holes for mounting your speakers.  I was able to get away with using a razor blade cutter to get through the leather sides of my case.  If a razor blade cutter is not enough to get through your suitcase, a jigsaw or Coping saw will probably do the trick.

Again, save these leather scraps, you might use them later in the project.

Step 7: Remove Front Panel From Subwoofers

Press the tabs around the inside edge of each of the subwoofer covers to remove the mesh front panel from the edge guard.

Step 8: Mount Subwoofers

The Pioneer kit comes with hardware for mounting the speaker components.  Use the eight longest screws in the kit to mount the two subs to the front of the suitcase.  Use a nylon nut to secure to back end of the screws and prevent vibrational loosening.  You might also considering finding a screw with a matching locknut.  File down the pointy edge of the screw so you don't accidentally scratch yourself.

Step 9: Mount Tweeters

I cut my backing wood panel with such a tight tolerance that the tweeters press fit into the side of the suitcase enclosure.  For added stability, I used the metal inserts and screws from the pioneer kit to hold the tweeters in place from the inside of the suitcase (though this is not their intended purpose, it worked really nicely for me).  Depending on your setup, you might also consider using some of the kit's other mounting options.

Step 10: Remove Lining of Back Panel and Reinforce With Wood

As with the front panel, use a blade to clear out any loose material attached to the back panel.

Step 11: Layout Remaining Components

Organize the remaining components around the back panel and mark drill holes.  I used two pieces of 2' wood scrap to prop up my charge controller above the surface of the plywood support.  Make sure the case will close before you finalize your layout!

Step 12: Passive Crossovers

The Pioneer kit comes with passive crossovers to split up each channel of audio from the amplifier into a signal for the sub and a signal for the tweeters.  Use screws to mount both crossovers onto the side of the suitcase, opposite from the speakers.  Note - nearly all of my screws were screwed through the 1/4 plywood backer, but not through the suitcase enclose.

Step 13: Wire Crossovers to Amplifier

Cut and strip a 2-3' piece of speaker wire (long enough so you can easily open the suitcase without putting tension on the wire) and use it to connect one crossover to the amp's left output and other to the right output.  Be sure to connect the + crossover input to the + amplifier output.

Step 14: Wire Woofers to Crossover

Strip two 2-3' pieces of speaker wire and solder the ends of one wire on each of the subwoofer terminals.  Connect the other end to the screw terminals labelled "subwoofer" on that channel's corresponding crossover.  Make sure that you connect the + crossover output to the + speaker terminal.

Step 15: Wire Tweeters to Crossover

Since the two tweeters have a resistance of 4Ohm, I wired them in series to the tweeter output from the crossover.  To do this, connect one tweeter's + lead to the + crossover terminal (you may need to lengthen the wire).  Then connect the - lead of second tweeter (of the same channel) to the - crossover terminal.  Connect the remaining two leads from the tweeters to each other to wire them in series.  Repeat this for the second channel.

Step 16: Secure Batteries

Use small L brackets to secure the two batteries against the lower corners of the suitcase. 

Step 17: Prepare Amplifier Power Cable

Cut the power supply that came with the amplifier and strip the wire.  The outside lead is - and the inside lead is +.  Connect the exposed leads to a piece of 1-2' speaker wire and cover the connection with electrical tape.  This wire will connect the amplifier to the charge controller.

Step 18: Prepare Battery Terminal Clips

Cut two more pieces of 1-2' speaker wire and crimp a 3/16" quick disconnect connector on one end of each wire.  These wires will connect the batteries to the charge controller.

Step 19: Connections to Charge Controller "battery" Terminals

Connect the + end of the two battery connections from the last step, and the amplifier power supply wire and crimp with one of the terminals included with the charge controller.  Do the same for the - leads of these three wires.  Screw the terminal connections to the + and - terminals of the charge controller, on the side labelled "battery".

Step 20: Wire Charge Controller to Batteries

Connect the quick disconnects from the charge controller to the batteries.  Make sure to connect the + from the charge controller to the + on the battery (and vice versa).

Step 21: Prepare External Power Supply Cable

Cut a 1-2' piece of speaker wire and attach an M-type barrel plug to one end.  Crimp the remaining two terminal mounts from the charge controller to the other end of the wire.  Then screw the terminals onto the side of the charge controller labelled "array".

Step 22: Mount Charge Controller

Now that all the connections to the charge controller have been made, use wood glue and a screw to mount two pieces of 2" wood block to the plywood panel.  Once the wood glue is dry, use screws to attach the charge controller to the front of these blocks.

Step 23: Remove Amplifier Front Panel

Use a hex key to remove the four corners screws on the front panel of the amplifier.  Use a tiny hex key to loosen the set screw from the knob, and remove the knob from the panel.  then use pliers to unscrew the nut attached to the knob's underlying potentiometer.  The front panel should come off easily.

Step 24: Mount Amplifier

Use a pencil to mark the place on the enclosure where you would like to mount your amplifier's front panel.  I mounted mine on the side of my suitcase.  Drill out holes for the 4 corner screws, potentiometer, switch, and blue LEDs.

My suitcase enclosure added about 1/2" of extra space between the front panel and the rest of the amplifier.  Since the original screws weren't long enough to cover this distance, I went to the hardware store and found some ~1.25" 3mm screws to replace them.

Screw through the suitcase enclosure to mount the front panel on the amplifier.  The amplifier is light enough that it will support itself by the screws alone.

Step 25: Connect Charge Controller to Amplifier

Make sure the amplifier is switched to the off position and plug in the connection from the charge controller.

Step 26: Mount External Power Supply Jack

Drill a hole in the suitcase and mount the M-type barrel plug.  My enclosure's walls were so thick that I couldn't use a nut to lock the plug in place, I supplemented with super glue.  You can use the 12V wall wart or even a 12V solar panel to trickle charge your batteries through this jack.

Step 27: Connect RCA Cable to Amplifier

Plug the red and white ends of the RCA cable to the amplifier input.

Step 28: Mount External Audio Jack to Suitcase

In case you want to access the audio in from the outside of the case, mount an 1/8" stereo jack to the side of the suitcase.  Use some 22 gauge wire to connect the leads from the jack to an inline female 1/8" stereo jack.  Use electrical tape to cover any exposed solder points.

This way, you can store your audio devices inside the suitcase by plugging them directly to the 1/8" stereo jack to RCA cable that is plugged directly into the amplifier.  Or you can plug the 1/8" stereo/RCA cable into the inline jack, and use a male to male stereo cable to hook up to the external 1/8" jack.

Step 29: Create IPod/phone Mount on Inside of Suitcase

To make thing really fancy, I used some of the extra fabric I removed in step 2, to create a little pocket for holding my phone/iPod inside the suitcase.

Step 30: Rock Out

You're done!  Have fun!  Be sure to check the voltage readout on the charge controller occasionally and make sure the battery doesn't get too drained (the charge controller won't be able to charge the batteries if they are completely drained).