DIY Portable Bluetooth Boombox in Less Than $8

How to make a portable and cheap Bluetooth Boombox

Hello friends!
In this instructables I'm going to show you and discuss how you can make your own portable bluetooth boombox within a budget of less than $8 with a total output of 8 watts which is also rechargeable and a lot cheaper than the cheapest speakers available online. The boombox can be used for indoor and outdoor purposes because of its loud and clear sound.(everything is cheap in India specially where I live the prices of every component is the cheapest)

Supplies

To make this boombox we need very cheap components and some basic tools easily available in home.

Components used -
1. Pam8403 amplifier module×1
2. Bluetooth audio receiver module×1
3. Tp4056 type C charging module×1
4. On/off switch
5. 1.5 inch 3 watt full range speaker×1
6. 2 inch 5 watt full range speaker×1

Note: I bought everything from my local store except the charging module that's why it became very cheap for me($8). If you buy everything from online ( amazon.in ) it will cost you about $10 - $15 which is a bit costly but still a nice budget.

Tools used -
1. Glue gun.
2. Soldering iron.
3. Handsaw.
4. Sandpaper.
5. Superglue.

Making the Front Panel

The first thing we need to do in this build is to make the front panel. I cut a parallelogram shape (see image) with handsaw and smoothen the edges using sandpaper. We need to mount the 5w speaker in the front panel. Due to unavailability of power tools, I used a screwdriver as a chisel and cut a rough hole in front. After that I mount the speaker with superglue and hot glued the edges for airtight. Once the speaker is fixed properly use black fabric to cover the front for a premium look.

Making the Sides(top, Bottom, Left, Right)

Once we've made the front panel successfully, it's time to make the other sides except the back as we need to add some components later. I've cut four pieces from mdf board using handsaw and glued them with the front panel. Make sure to cut holes for switch, speaker and handle in the top panel and cut a little gap in the right panel to mount charging module. after the glue dries, sand the panels using sandpaper for a smooth surface and pour some good quantity of hot glue from inside in the joints of the panel to make it airtight.

Adding Electronics

Once we've done making the speaker body except the back, it's time to add electronics in it. For the bluetooth and amplifier I'm using Pam8403 amplifier module and a cheap bluetooth 3.0 audio receiver I bought from my local store for less than $2. Now we also need a power source to power it. As the bluetooth and amplifier can run within a voltage of 3 - 5v we can easily use 3.7v batteries to power it. But if you really want to run it for weeks or months with a single charge, I'd prefer you to use a power bank of a minimum capacity of 10,000mah or more to power it. But as I need a maximum playback time of 50-60 hours(80% volume) in a single charge, I'm using two 18650 lithium ion cells I bought from my local store for $2.5 connected in parallel with a total capacity of 4,400mah(2,200mah each). As they've a charging cycle of around 300 charges and discharges, I used battery holder instead of soldering them as I wanted my project to last for a couple of years atleast and can change the batteries if needed. For charging the batteries I'm using a Tp4056 type C charging module I bought from amazon for $1. Type C modules are usually designed for fast charging that's why I'm using it. Now here comes the most important component, the speakers. Speakers need to be of good quality for better performance, that's why I'm using two good quality speakers. One is of 3watts and 1.5 inch in size and another is of 5watts and 2 inch of size. I bought both speakers for $2 from my local store. A block diagram of the connection is given above for better understanding. Make sure to hotglue the batteries with the battery holder as the batteries may tend to go loose. After soldering every components with one another, hotglue everything in place and make sure no loose wire is around.

Making the Back Panel, Mods and Conclusion

Once everything is soldered properly and glued in place, check if everything is working properly. Now again cut a parallelogram shape of the same size of the front panel to make the back panel. Cut a little gap at the left side for the charging module. Now cut two holes of 1 inch diameter in the panel's bottom. Cut two small pieces from a 1 inch diameter pipe and glue them in the holes as shown in the above images. They will work as the bass tube of the speaker. Use hot glue only to fix the back panel as it may needed to open the speaker in future to replace the batteries. I noticed it keeps shaking a lot due to heavy bass, so I used small pieces of glue stick to make its rubbery feet. I also attached a plastic handle at the top to hold it and it looks awesome. After everything is done, sand the speaker well for a smooth surface. You can also paint it or decorate it with vinyl but in my opinion, it looks good so I'm leaving it with its natural texture. A video is given above to understand everything properly. You can find the soundtest video link in the description of that video. The bluetooth boombox just sounds perfect at 90% volume and gives some really great bass. I hope you like my project, if you've any doubts and queries, feel free to comment and I'll answer it asap. Also please upvote me in the contest if you appreciate my hardwork. Don't forget to check out my YouTube channel here and follow me to watch my other instructables here.