I set out to make a decent sounding and inexpensive 3d printed Bluetooth speaker. It is simple in design and the components are readily available! To see how I put it together, check out this YouTube Video: 

 Parts List and Links:

1) MH-M38 5Wx5W Bluetooth receiver and amplifier

 ( https://www.amazon.com/gp/product/B0B9XK4C2D/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1 )

1) 1S lithium BMS ( https://www.amazon.com/dp/B08VDL8YFB?ref=product_details&th=1 )

2) Speaker Drivers from Parts-Express ( https://www.parts-express.com/YDP512-12-2-x-4-3-8-Paper-Cone-Shielded-Full-Range-Speaker-8-Ohm-15-20-289-2346?quantity=1 )

1) 18650 Battery holder ( https://www.amazon.com/DIANN-10pcs-Battery-Holder-Single/dp/B0BJV7SK5D/ref=sr_1_3?crid=3AL4DLFVI81KK&dib=eyJ2IjoiMSJ9.jTaJ82G6c0qakGO1c27iUvU4yoDGNMvF2j-zx6b908Xpa-_XWRPbSbIoHhy3acMlVLo8GDhOCUzCc_wkxTCvJCTyNbY4eVvuJB2BALsCnQcQZZxUa92RSz9O6QvNdsbHDNOevH596niw7Z0zy6EQ72qKZDoPBfArr2_BHtqqtSB_uwjDhutL79nhEUWarlA2jDnwwNnpaGJR2eFcCsjqm8Fa2zi0Q1By--E6sQ3Twt3XwYApm9G-SeqTf314JAjrRlf4drXixHfsFNlwrMeeJl9NyQxfgFr9h9fUSbxYR3k.YhIVdRdLqWvE8F7F9gUt5UGtTbt1I0FR0K2zYqHCKHM&dib_tag=se&keywords=18650+single+battery+holder&qid=1718040836&s=electronics&sprefix=18650+single+battery+hold%2Celectronics%2C135&sr=1-3 )

1) 18650 Cell ( https://liionwholesale.com/collections/batteries/products/dmegc-inr18650-29e-18650-10a-flat-top-2850mah?variant=39353214500933 )

1) On off Switch ( https://www.amazon.com/dp/B07BPKYV3M?ref=product_details&th=1 )

9) M3*6 bolts ( https://www.amazon.com/1305Pcs-Metric-Assortment-M2-M3/dp/B0CBWR9YB9/ref=sr_1_3?crid=UJE3KXTW2Y1O&dib=eyJ2IjoiMSJ9.3NlLNgD8NWBmVXJg_C8TTanAH8jPdPMwp0QiO23bXG5B_92lyctAd_LkDVyRqcKW2SvL6zHbiPmlgs6uXfMWVvdT8KQ8GTkddMeCAy3Og-R5N8AjQp1nUme511zoMBY5.1O8tTMgXs6AKn3FBv0Ykk_jN3fYNlaNW1eDaT58RjZk&dib_tag=se&keywords=1305+button+head+hex+socket&qid=1718725967&sprefix=1305+button+head+hex+socket%2Caps%2C113&sr=8-3 )

9) M3*16 bolts ( https://www.amazon.com/1305Pcs-Metric-Assortment-M2-M3/dp/B0CBWR9YB9/ref=sr_1_3?crid=UJE3KXTW2Y1O&dib=eyJ2IjoiMSJ9.3NlLNgD8NWBmVXJg_C8TTanAH8jPdPMwp0QiO23bXG5B_92lyctAd_LkDVyRqcKW2SvL6zHbiPmlgs6uXfMWVvdT8KQ8GTkddMeCAy3Og-R5N8AjQp1nUme511zoMBY5.1O8tTMgXs6AKn3FBv0Ykk_jN3fYNlaNW1eDaT58RjZk&dib_tag=se&keywords=1305+button+head+hex+socket&qid=1718725967&sprefix=1305+button+head+hex+socket%2Caps%2C113&sr=8-3 )

Crimp Kit 

( https://www.amazon.com/gp/product/B0BZ49GH6D/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1 )

Here is a Link to a PDF with information on the MH-M38 board. https://www.sunrom.com/download/705.pdf

Hot glue was used to hold in the BMS board and seal it. I left a hole in the backplate to allow the light from the BMS board to shine through! 8 of the M3*6 bolts are used for the speaker drivers and the other one is used to hold the MH-M38 board. The 9 M3*16 Bolts are used to hold the Backplate to the enclosure. I also included a seal made of TPU to help mitigate vibrations and air escaping. Thanks to a friendly commenter on Facebook, I found that it sounds better if you put a little bit of “fluff” in the enclosure before you close it. You can use poly fill, or any stuffing type material. I used the left over innards of a dog bed that my pup destroyed! I don't have any legitimate measurements, but seems to sound better to the old ear! Thanks for checking out the project! If you have any Improvements please let me know!