Introduction: INSANELY Loud 150W Bluetooth Speaker Boombox
Hello everyone! In this Instructable I will show you how I built this insanely loud Bluetooth speaker! A lot of time has been spent on this project, designing the enclosure, gathering the materials and parts of the build and overall planning. I have included the build plans and laser-cut plans, that you would need in order to build this speaker by yourself and the wiring diagram is free download and you can find all o these files in the bottom of this intro! Make sure to zoom in to see the connections up close! You can also find all the links for products in Step 2!
Step 1: Plans, Materials and Design
The main objective of this project for me was to build a decent looking, not too much volume-occupying Bluetooth speaker that would provide plenty of power into the speakers. Therefore for this speaker I chose a pair of MOREL MAXIMO 6 6.5" 2-way speakers, which can easily take up to 180W RMS of power. They provide crisp and boomy sound, without overwhelming bass.
I designed my speaker on Sketchup, which is a free program for designing - simple to use and can create great results. I also needed to use Autocad for sketching out the laser-cut parts.
The materials that were used were 12mm MDF board and 4mm plywood.
Step 2: Parts and Tools
- Speakers - https://bit.ly/2RK2FQR
- TDA7498E Amplifier - https://bit.ly/2r332uQ
- 36V 6.5A DC Power Supply - https://bit.ly/2DzN5z3
- XR1075 Preamplifier - https://bit.ly/37YZqdU
- Bluetooth V4.0 Board - https://bit.ly/2rMy76k
- AC-DC 12V Converter - https://bit.ly/37WQMg7
- Self-locking 22mm 220V LED Switch - https://bit.ly/35Vty8a
- 19mm Latching 5V Blue LED Switch - https://bit.ly/2Y7Ahct
- Isolated 5V Converter - https://bit.ly/33wQxVK
- Step Down Converter - https://bit.ly/33AyIoQ
- Audio Input Jack - https://bit.ly/34F8eDZ
- 3mm Double-Sided Tape - https://bit.ly/2P6L6rc
- M2.3X12 Screws - https://bit.ly/2rmLkCj
- M3X10 Bolts and Nylon Nuts - https://bit.ly/2DBH9Wa and https://bit.ly/37Rg4w5
- Audio Input Cable - https://bit.ly/2rFtScH
- Rubber Feet - https://bit.ly/2rkXvQo
- USB Panel Mount Socket - https://bit.ly/35WpXHk
- AC Socket - https://bit.ly/2Y7eXnz
- AC Cord - https://bit.ly/2P1GByo
Black Leather Vinyl - https://bit.ly/2sBuUH4
TOOLS and MATERIALS:
- Multimeter - https://bit.ly/35QJQPN
- Hot Glue Gun - https://bit.ly/37U9CVh
- Soldering Iron - https://bit.ly/2OByoR7
- Wire Stripper - https://bit.ly/2XZ9kI8
- Cordless Drill - https://bit.ly/35SfH2B
- Jig Saw - https://bit.ly/2OCt40V
- Drill Bits - https://bit.ly/2KHTEn6
- Step Drill Bits - https://bit.ly/37uUPQz
- Forstner Bits - https://bit.ly/35snpjW
- Hole Saw Set - https://bit.ly/34cTlZj
- Wood Router - https://bit.ly/2rj2lNI
- Roundover Bits - https://bit.ly/2OYaDTw
- Center Punch - https://bit.ly/2OzuhVG
- Sanding Sponge - https://bit.ly/35sQJ9T
- Solder - https://bit.ly/2XNOUSt
- Flux - https://bit.ly/33eXs5I
- Soldering Stand - https://bit.ly/2P4QOK7
Step 3: Preparation
To start the project off, I asked my friend to cut up my MDF boards into manageable pieces with his complex table saw, worth thousands, that he owns. But of course, such equipment is not necessary for this project! The cuts must be down to a millimiter, but that does not mean that the same results can’t be achieved with a jig saw or a circular saw! Trust me, almost anything is doable with simple tools, patience and skill. Although, I would advise you to find someone who could cut you out the plywood panels with a laser cutter.
After the boards have been cut into necessary sizes, I marked the points for the speaker cut outs, making sure it was equal distances from both sides o the front panel.
Step 4: Cutting Out the Circles
I then took a 3 mm drill bit and drilled through the boards in the exact centers of the circles. I used a router and a jig that I made myself to cut out the circles in the boards. Once again, such tools are not necessary to achieve the best results. Almost the same result can be achieved by using a jig saw and a few minutes of sanding. The main advantage of this circle jig that I made is that it allows you to cut circles of precise diameter, without any run outs. I did mess up cutting the circles out a few times, mainly because I did not tighten the router bit well enough. Learning from mistakes! Also, cutting MDF boards with a router is one good way to make clouds and piles of dust that is not good for lungs! Respirator and a good dust collection system is necessary when working with this material!
Step 5: More Cutting!
For this step I once again used my trusted router with a jig that follows along an edge to cut wood precisely. Here my objective was to cut a 1 mm (almost the thickness of the vinyl which will be used later) deep groove in each panel’s edge (two sides, top and bottom panels). This hardly noticeable groove will be very handy when wrapping the box in vinyl later, since it will give me an edge to cut the vinyl and will also create a smooth transition between the vinyl and the MDF board.
Step 6: Front and Back Panels
To create a nice looking cutout for the back control panel I used a template which was cut using a laser cutter. By firmly holding the template in place, I traced around the inside of it. I then drilled four holes in each corner of the traced out rectangle, using the biggest drill bit I had, making sure that the holes are close to the traced out line, but not past it. Then using a jig saw I cut out the rectangle, making sure I stayed close to the line, but not too close. Double sided adhesive tape was the placed around the line and the template was pressed on it making sure the edges of it align with the line that was traced out. I then placed a flush trim spiral router bit into my router and continued cutting along the edge of the template. The bearing which is on top of the flush trim bit rides along the edge of the template, cutting any material along its path and leaving a pristine finish and straight edges. Once again, dust collection and a dust mask are a MUST!
I then followed up with a rabbeting bit, creating a ledge that will be used to mount a laser-cut plywood panel. The same steps as mentioned above were repeated to the top panel, only using a different plywood template. A round over router bit was also used to create a curve along the top panel edge.
Step 7: Glue Up!
With all the panels prepared, it was time to glue them together. I used a healthy amount of glue along the edges, making sure it was spread along the whole surface area. With all the pieces glued together, I placed a few weights on top to make sure they are pressed well. Also, make sure you check that all the corners are square, you may end up in big trouble later if they are out of square! After the glue has dried up a bit, I glued four support pieces in the back of the speaker, which will be used to screw the back panel in.
Step 8: Making Sure the Edges Are Straight
Once the support pieces have been glued in place and the glue still wet, I put the back panel on top and used a hammer to give it a few knocks to make sure the panel sits flush with the rest of the speaker panels.
Step 9: Once the Glue Has Dried
I drilled four holes on the bottom of the speaker enclosure for the rubber feet to be screwed in later. After that the round over bit was used on all outside edges of the speaker making it smooth to the touch. I then placed back the back panel and inserted a few plastic pieces on each side as shims to center the back panel and drilled holes for the screws that will hold the back panel in place. With that done, I proceeded to sanding the laser-cut plywood pieces with a fine sandpaper, to remove any burn marks or splinters. I then sprayed the plywood pieces with lacquer to create an even coat. Once the lacquer has dried, I put the back panel piece on the back panel and drilled the holes with a tiny drill bit, so that the screws have something to bite into. After that I used a screw to which I made a few cuts to help me cut threads inside the back panel.
Step 10: Applying the Carbon Fiber Vinyl
I would consider this to be one of the trickiest and most patience-requiring steps of the build. Your best friend here is heat – which you can easily obtain from a heat gun I listed in the Tools list above. It is important to not keep the heat gun too close to the vinyl or it will melt immediately. Just apply enough heat until you are able to stretch out any wrinkles that may appear on the panel. But going around the curves of the circle cut outs may be even more tricky because it requires more heat to be able to pull the vinyl around the round edge, but not too much heat so that it does not melt. Make sure you practice on something else if don’t have too much vinyl on hand.
Step 11: Applying the Leather Vinyl
Firstly I applied paper masking tape along the edges so that I do not apply contact adhesive where it is not necessary. I used a somewhat stretchable matte black leather vinyl for the enclosure. To me it looks great, is not too difficult to work with and is quite durable and resistant to scratches and dings. To glue it on the enclosure, I used a decent amount of contact on both mating surfaces – the MDF of the enclosure and the back side of the vinyl. After letting it settle for a few minutes, I pressed the straight edge of the vinyl in place along the line on the enclosure. Such spots as the top panel, the meeting edges and corners did require more effort to lay the vinyl without wrinkles but it was still doable and turned out nicely. There were some adhesive still left on the vinyl but it was easily rubbed off later. After the vinyl was tucked inside the edges of the enclosure, I used a sharp utility knife to cut off the extra vinyl, leaving a flawless finish all around.
Step 12: Final Glue Up
A long waited step! I finally got to gluing in the front panel! I spread wood glue along the edge and placed the whole front panel inside the enclosure. I made sure that the edges were flush and it fit just perfectly! I also made sure to apply plenty of glue from inside of the enclosure. After that I glued the laser-cut plywood panel from the inside of the enclosure, also making sure to seal all the edges around.
Step 13: Electronics
First of all I screwed the drivers in place and placed the tweeters. I used hot glue to go around the edges of the speakers making sure they are sealed all around. I then heated up the soldering iron for some work up ahead. To begin with I desoldered the potentiometer from the amplifier board and used 6 thin wires to make an extension for the potentiometer. I then did the same with the preamplifier board potentiometers, but here I only extended the BASS and TREBLE potentiometers. Also, I turned the potentiometer on the preamplifier board all the way clockwise and backed just a tiny bit so that it does not make hissing noise. I then soldered an extension for the AUX input cable. I screwed the power supply to the back panel and glued the amplifier on the opposite side. I took apart the crossovers and glued them on the bottom of the enclosure, so that the screw terminals face the back of the speaker. Then in the video I took apart an old 12 V DC power supply which will be used for powering the preamplifier board and the Bluetooth board, but you can also use the AC-DC converter I listed in the Components list above. I made the necessary connections for the amplifier and power supply board. In the video you can see that I also installed RCA connections, but since I thought they are not that necessary, I did not include them in the components list, so feel free to remove them from the laser-cut plans if you would like. Once the wires were soldered, I pushed them in place and used a nut to screw them tightly in place.
Step 14: Last Steps
I applied a strip of double sided foam tape along the back side of the speaker. This is necessary so that the speaker is fully sealed and no air leaks out. A dab of epoxy glue was spread around the potentiometers and the AUX jack so that no air leaks out. The back panel was pushed in place for its last time and screwed down using appropriate wood screws to hold it in place. Then the AC power jack and the panel mount USB port were screwed in place and hot glue was used to seal them so that once again, no air leaks out. The smaller back panel was then also put in place for the last time. Then the rubber feet were screwed to the bottom of the speaker enclosure. I applied a dab of the same epoxy glue inside the potentiometer knob so that it stays in place. You can also see in the video that I used a few pieces of plastic to raise it up from the panel so that the knob does not rub against the panel.
Step 15: Final Touch!
The most rewarding step! I started by applying some black paint on the letters, then sanded the plywood logo and sprayed a thick coat of lacquer on the logo. After it was left to dry for a good amount of time, I used some masking tape to make sure the logo is centered and drilled the holes to hold the speaker in place with screws. That’s it! Time to blast the speakers!
Step 16: Final Thoughts!
I think this project turned out great, not only does it look decent, but the sound is just incredible! I can’t express how loud it is for its size, just the tiny adjustments of the loudness potentiometer makes the speaker BLAST. It fills the room with plenty of bass which can be adjusted to everyone’s needs. It is also very easy to use – tunes can be streamed through Bluetooth or using the AUX port through a cable. I also really like the illuminated switches which are used as the power and Bluetooth buttons. It makes it clear when the speaker is connected to a device via Bluetooth – the blue light then stops blinking.
Thank You so much for following me through this tutorial! I hope I have managed to inspire you to create your own speaker using my or your own design :)
And that's how my Bluetooth boombox came to be! It was a pretty cool project that helped me improve my skills, and I truly hope that you learned something new as well. If you have any questions, feel free to ask in the comments. Also consider visiting my YouTube channel for more videos. Thanks!
1 Person Made This Project!
- FelipeR123 made it!