Intro: Powerful 2.1 Portable Loud Boombox
I decided to do my own boombox, made the case from two old speaker shells
Check the video above for sound samples.
These are the components that i used:
18650 Holder: https://goo.gl/vrUC2A
Step down module: https://goo.gl/f3tkiU
Amplifier 30W https://goo.gl/gRmnev
or 50W: https://goo.gl/jPK294
Mp3 Module: https://goo.gl/Er4kUQ
4S: tester: https://goo.gl/GQCnch
18650 Batteries: https://goo.gl/iS1MTW
Power jack: https://goo.gl/AL7bgU
The speakers have 60w each with tweeters attached, the subwoofer was from an home 5.1 cinema kit i believe.
Step 1: The Case
I made the case from two empty speaker shells, in one speaker case i close all the original holes and made one new hole for the subwoofer, for the other speaker case i cut it in two, it is going to be the top part of the case where the display, electronics and tweeters are located.
Just need to glue them in place.
Step 2: Front Panel
I painted the part that i want to cut using the top part of the case as a template, mark the holes to drill for the amplifier and cut a rectangule with the same measures of the mp3 module.
Mark the holes for the tweeters, find the middle and cut a circle of wood for each one.
Step 3: Subwoofer Compartment
Put the subwoofer in place and flip the case, put a small piece of wood on the subwoofer to avoid the speaker to touch the wood.
Cut a piece of wood to place inside the box, it should be a nearly perfect fit to avoid gaps, cut four pieces of wood to creat a framme around the new divisory.
Step 4: Final Shape
Using small pieces of wood mark and glue them to keep the amplifier and the front panel in place, also glue the top part to the main part of the speaker.
Step 5: Speaker Holes
Drill a hole for the subwoofer vent, and glue a piece of cilindrical cardbord, for the front measure each speaker and cut the holes, in my case i´m using diferent sizes speakers with the same voltage.
Just need to had two pieces of pre-cuted plywood to form the cabinets(small)
Step 6: Final Touches
Painting using a water based mate black, very easy to apply and very fast dry, hot glue the tweeters and mark the grill mesh to bend half a centimeter to 90º in alll the four corners, using two pieces of wood its easy to hammer the metal to the desired shape.
Step 7: Put It Together
Its almost done, solder everything using the schematic, all the exposed solders wires must be heat srinked with srink tube, the main components are:
Mp3 module (7 to 12 volt)
Step down module (set to 9 volt) power to the mp3 module
Amplifier (12 to 25volt) connected directly to the 18650 battery or 20 volt 6A laptop charger
Two stage switch, 1st position battery, 2nd position off, 3rd position charger
The battery tester is connected directly to the battery output, it uses a momentary switch to turn on
I bought also a 4s 18650 module charger with protection but decided to use an exterior charger for the batteries, if you have 8 batteries you have twice the hours of music !!
Step 8: Test It
Its very loud and stable at maximum volume, you can use sd card, pen drive, bluetooth, line in, it has radio with antenna connection, can record sound and it have a remote control.
You can also use random play, repeat folder, folder select, 10 seconds music play and auto change to next song.
I´m very satisfied with the final result, you can see it working in the video at the first step of this instructable.
Tank you for watching ;)