I have been watching instrutables for a while and also YouTube videos and forums. this is from where all my ideas came from. to make this little boombox i used a wine bottle wood case which i cut down to a smaller size ,a 12v 12ah battery, a lepai 2020+ amp, two speakers i found at a local thrift shop and a volt meter, plus a couple of spare wires i had laying around.
total cost was about 75$
battery at a local warehouse 15$
lepai amp- 20$
speakers at a thrift shop-8$
Bluetooth module-8$
battery charger-15$
volt meter-6$

Step 1: Box Sizing

Originally the box was twice as big, first i took it all apart and then i measured how much space i needed for the speakers and the battery, then i cut all the pieces and i put it back together and made the front and top removable.

Step 2: Opening Front Holes for the Speakers and Amplifier

On this step i tried measuring the speaker position but it did not work out the way i wanted it to so after the holes were cut out i had to cut the 3 piece speakers in pieces to make them fit correctly, to glue them to place i used gorilla glue epoxy.

Step 3: The Electronics

to power this boombox i used a 12v 12ah battery which gives me 6min-to 10 hours playtime from moderate to hi volume. the amplifier is a lepai 2020+ its an awesome little amplifier! i had to buy two due to an error on my wiring diagram i fried the first one :/. the 12v voltmeter lets me know how much battery i have left and the Bluetooth module gives me wireless connectivity. the power converter for the Bluetooth module is a standard car plug usb adaptor with 2 outputs so i have 1 extra to charge my phone on the go... the speakers are hi-fi grade with the subwoofer tweeter and super tweeter they run for 40$ the pair and they're waterproof but i got them for 8$ !!!!!...

Step 4: "Wiring Diagram"

this is the worst diagram i have created yet, if you have any question please feel free to comment and ask... i can either play from the battery or from the wall charger, the wall charger is a. 12v float charger to which i adapted a plug that plugs into the back of the boombox

Step 5: Finished Product!

the boombox came out overall great! the bluetooth reception is rather weak... the slide in top was made out of a really thin plywood and it would vibrate and rattle too much so instead i used a thicker mdf board which worked beautifully!!! I already took the speakers to a baseball game and it lasted 6 hours! and with still juice to go!. i dont let the bttery go under 12v because my charger wont recharge it from lets say 9v to 12, instead from 12 it hold the battery charge to 13.4 and i can leave it connected always without harm to the battery... from 13.4v in the battery to 12v should be around 8 hrs playtime depending on volume and temperature...

Step 6: Video!!!!

Homemade portable bluetooth boombox Youtube VIDEO