From the first Project I started, I had always wanted to do Bluetooth Speakers. I wasn't skilled at any electrical, so I started my research and watching hours and hours of videos. 100's of projects later, I finally felt comfortable enough to start building them. I had already purchased most of the main components, and they just sat in a box for the past 3 years until now. I have built around 6 total, with this one being my second published video on BT Speakers. The other videos will be coming as I edit. Projects are done, just need to find the time to edit and do an tutorial. Please like, subscribe and share and most of all enjoy!! In this project, you will also see me built a 18650 3s pack with BMS, Post on Youtube and Build a Great looking Bluetooth Speaker
Sound Check Video at the end of this tutorial. Unfortunately, I do not have the equipment yet to test and post, I had to use my wife's android. The system sounds great and has a bass that hits you solidly in the chest. Not bad for mini 1" speakers. Music By Fred & Sound- With permission from Fred & Sound, music is copyright Protected. "Bass Protector". Check out the links in the video description and his channel. Contact him if you would like to use his music.
In this project, I originally had a different design in mind, down to my Circuit/Pictorial. Later I realized I did not have the room for the 18650s in any form (parallel or series). That was one mistake, my other mistake was the actual placement of the drivers. I had to add a 1/4 x 1/4 strip on both the face and back to extend the case. Not sure if you will see that in this tutorial, but you will see it and I explain in the video.
I decided, with the speakers in series, each one is around 3.7ohms. It would be just enough at 12V that the amp would supply 8-12watts. Perfect power for each speaker.
Dayton Audio CE Series CE32A-4 1-1/4" Mini Speaker 4 Ohm-
TPA3110 2x15W Digital Stereo Wireless Bluetooth Audio Amplifier Power Amp Board-
The passive speakers I got from Amazon, but seller changed the link to a charger. I have not been able to locate the same type, local in the US again.
All other parts are mainly parts reused from older BT speaker (3s Lithium Polymer) and DC Jack I had purchased a few years back. Very minimal Components used in this build as the Amp has everything needed.
I like to stage all parts and pieces I am going to use, just so I get a rough idea of the build. This lets me know who I might throw it together. main components are listed above, please contact me if you have an issue finding anything else. Most of these items were purchased a couple of years ago, so the links I would have used. Speakers I got from Parts Express.
To prevent marking up the oak and having to erase any markings. I use masking tape before I start the process. Just encase I mess up. If I mess up, I simply pull off the masking tape and start all over with no harm to the case. Using the Calipers, I measure the speaker's diameter and divide that by 2 to get my center. I place the speakers on the case to figure out where I want them placed. I also like to write the measurement of the cutout next to the dot I mark for the cutout. Oak is one of the more spendy of the hobby woods. So make sure you have them marked exactly where you want them before doing any drilling. Hobby wood I had laying around from an earlier project. If I had to guess the cost of the wood was a cheap 5-10$ for a 3-foot piece.
Because oak is pretty hard, I used a punch to help mark the holes I need before drilling. Next, I started with the smallest drill bit I had and worked my way up to 3/16. My hole saw uses a 1/4" so the 3/16 holes help guide the hole saw when cutting out all holes needed. I also decided it would be easier to punch and drill if I added and glued the top side and bottom of the case together. The hole saw I used was 1 1/8" on the speakers and the passive was 2 3/4 x 1 1/4. I pulled off all masking tape and used sandpaper and files to clean up edges for now.
With a DIY Dremel router table I made (Video and tutorial coming soon). I cleaned up all edges with a 120 grit drum sander(Dremel). Then I put a 1/8 round-over bit in the router table's Dremel and put a small profile on all edges and holes.
With some oak stain I had, I quickly added stain and cleaned off an excess, to let it dry. While it dried completely, I drew up the Schematics using 4 x 18650's in parallel and a boost converter to 12v. The reason I am adding this part is- the schematics I drew up would have worked and may work for your build. Unfortunately, I found out later in the build, that this would not work, and neither would it work in series, without the boost converter. The batteries were hitting the passive radiators. Drew up an easier, better schematic later on.
Later on, I plan to put a coat of clear on the bt speaker, so before adding any drivers. I marked each hole and passive on a small piece of cardboard to cut out later. Making sure to write in the hole where it goes. Then I drilled the 3 small holes in the back. One for a led, one for the power and one for the TP4056 (later hole is inlarged for DC connection when the schematic is changed). I used a Dremel, glass bit to do the fine cleaning on the TP4056
I used a smaller 14 gauge silicon wire and made sure each component had black and red wires soldered according to the polarity on the component. Then I did a quick test of the Boost converter, I did not use and adjusted to 12V. (boost converter is not used at the end of the BT speaker)
To attach the passives, I used Silicon adhesive with a q-tip and a battery to hold pressure till dry. Then I used SuperGlue Gorilla Gell to attach the drivers or speakers. Make sure the wires are facing the correct direction. After everything has dried, I used Silicon adhesive again to add a bead around each driver and passive. This ensures do air leaks after I build the unit.
Here is where 2 of my mistakes collide and I figured out how to fix them. Here I added 1/4 x 1/4 oak strips to the front and back to make sure I had room. Then I glued on the face. I used Hot glue on the inside to help plug any leaks. I used glue on the outside to fill any cracks. The glue will dry and you won't even notice it thereafter I clear coat. I also decided that the 4 batteries in parallel was too big, so I would try a 3s1P. Later I found the 3S was a little too big also and barley touched the passives. Adding the 3S or a 12V battery means fewer components. I would no longer need the TP4056 or the boost converter. So I used the hole the Tp4056 would charge from and drilled it big enough for a panel mount DC jack. I also added stain to the oak pieces before I glued them on
Here I soldered each speaker in series, so I would get around 9-10 ohms of resistance. Then as you can see, because I decided to go with 12V, I changed the TP4056 hole to a dc jack. I installed the DC jack, on/off switch and LED. Then I use Silicon adhesive to make sure there were no leaks.
Here you will see the old battery and the new battery. The Li-Po is smaller and skinnier. It also has more capacity. Because I plan to use This chemistry I deiced to add balance leads on the back of the case. I used a basic female 3s x 2 connectors and little leads to connect through the wood, this ensures I can use a hobby charger with an extension I made to balance batteries at any time. I can even connect the ISDt8 to balance when not charging. I try and do this with anything I build that uses a series battery.
The DC Plug is made, where you plug in a DC Male and it cuts off power to the main device, going straight to the battery. Without the plug, the power goes to the switch and then to the amp from the battery. This protects the amp when charging. I also added an LED so I would know when there is power on. Then I added a deans plug, that plugs directly into the lipo cells. The other red and black wire go to the power in of the amp. Pretty simple and basic.
I decide to add some Kapton Tape and cardboard on the battery for protection. I also added 2 small pieces of 1/4 x 1/4 wood to make sure the amp, didn't rest on top of the battery directly. I used silicone adhesive to glue together. I also added 2 heatsinks to the amp. After the amp/battery combo was complete. I used adhesive to glue to the box, but before, I soldered the amp directly to the speakers. using 2 small ferrite core wrapped a couple of times on the speaker wire in the middle.
Last part of the electronics. I simply connect the bare red and black wire to the bare red and black wire on the amp. Then I plugged in the Dean's plug to the battery and last I plugged in the balance leads to the panel. I add wood glue and silicon to the back and clamp it all together. Let it dry.
In the beginning, I made some cutouts to use when I clear coat. I added little handles to them and placed them as I had them labeled on the speakers and passive. Then I used masking tape around the switch and DC Jack. Last I took outside and put 3 layers of clear coat. After it dries, I pulled the masking tape and all the cutouts by the handle I made. Last adding some small feet to the unit.
This I just added 2 Ballance cables, soldered and added shrink tube or Kapton tape for protection. I will need this later when balancing and charging with a hobby charger. The last picture shows the cheap 12.6V charger and ISDT showing it balanced.
It's not the greatest, but you can definitely see how more simple these changes were. In the end, The schematic should have been only a 12V battery, speakers and amp. To get a more detailed explanation, please watch the video. I added that info in the begging.
The Build was actually pretty easy. But I wanted to add all the simple mistakes I made to show, not all projects go flawlessly. Some take some bumps and you have to figure it out. In the end, It was easier to build than I made it out to be. The sound is crazy awesome and the video does not do this system justice. For 1" speakers, I can feel the bass deep in my chest and the stereo quality is crazy awesome. Dayton Audio surely knows how to make them. This is the end of my tutorial, please feel free to ask me anything about the build. Here is the test video I did. Unfortatntly I don't own the proper recording equipment, I had to use my iPhone. The video does not do the speaker justice. Please enjoy and Look for my next Bluetooth speaker or DIY Project on my channel. And if you visit my channel, please like subscribe and share!! Thanks for reading my tutorial!!!