instructables
DIY HANDBUILT PORTABLE BOOMBOX
by patrick panikulam
Hello everyone , so in this instructable I will be The boombox is designed with dual rear facing showing you guys how I built this simple boombox passive radiators .Passive radiators acts as a using plywood by means of a few handheld electric substitute for bass ports.They take up less space tools.Building speakers as well as other small inside the enclosure as compared to bass ports and projects which I could actually use in my day to day prevents vent airflow noises as well.But what I love life has always been my passion and kind of like a about them the most is to see them vibrate when the hobby as well.We all love that feeling which we get bass hits which makes the whole boombox look a lot when we get to tell others " Yeah, I made that " ;-) . cooler ;-) .
So this is a really simple boom box that is entirely The boombox runs on a 12.6 volt ,3S 2600mah 18650 made out of plywood and MDF board. It took me 9 battery pack which gives upto 6 hours of playtime days to built as I only had limited tools.This boom box depending on the volume.You guys could use NCR has 4 speakers - two subwoofers and two tweeters 3400 mah 18650 cells for longer play time. which gives out a total of 30 watts of power. I have used 2 different kinds of tweeters- a silk diaphragm The boombox supports FM,USB, bluetooth,SD ,AUX as well as a piezo electric one.I decided to do this and also comes with an IR remote and on-speaker because I realised that the piezo tweeter covered the buttons for easy music control and tuning. really high frequency notes better than the silk diaphragm tweeter.
DIY HANDBUILT PORTABLE BOOMBOX: Page 1 Step 1: THINGS YOU WILL NEED :-
DIY HANDBUILT PORTABLE BOOMBOX: Page 2 I ordered almost all of my components from face any heating issue with the amplifier.Here I have AliExpress.Most components are cheaper there but it chosen a pair of 3 inch ,4 ohms woofers which might take upto a month or two to arrive at your place according to the datasheet of the amplifier will be according to where you live . aperfect match.
1. YAMAHA TA2024 Amplifier X 1: 3. DC-DC step down Buck converter X 1: http://s.aliexpress.com/uUZbeamQ?fromSns http://s.aliexpress.com/JfiaiIv2?fromSns
TA2024 is a special class T amplifier.And whats special about class T amplifier is that it offer both the This is a module that uses the principle of switching audio fidelity of a Class-AB and the power efficiency to very efficiently step down the voltage.It is by every of a Class-D amplifiers.Its a15 watts per channel way better and way more efficient that any voltage amplifier when its running on 4 ohms load . I have regulator ICs like IC7805 . Our project needs it used this amplifier before on an other project and was because we are using a 12.6 volt battery to power a impressed by the fact that it dosn't heat up as much 5volt audio decoder.So we need it to stepdown 12.6 as other amplifiers with the same specifications, so volts to 5 volts. thats why I decided to use this amp for this project. 4. Passive radiators (60X90mm) X 2
2. 3 inch ,15 watt sub Woofers X 2: http://s.aliexpress.com/fUJf2uQZ?fromSns http://s.aliexpress.com/MvueueM7?fromSns Passive radiators are a substitute for reflex or bass ports. Usually for small enclosures,production of low Always choose a speaker whose impedance matches frequency requires a long port ,so passive radiators with the amplifier that you are using so that you wont are used instead.Passive radiators also avoids air
DIY HANDBUILT PORTABLE BOOMBOX: Page 3 flow noises which usually occurs in ported 8. XL6009 DC Adjustable Step up boostconverter X speakers.The main factor affecting the performance 1: of a passive radiator based speaker is the mass of the metal plate on the radiator . The mass should be http://s.aliexpress.com/QnyEFR3a?fromSns varied for tuning.When using woofers , always try to go for a passive radiator that is the same size or bigger than the speaker(not too big).In this project I This module also works on the principle of have chosen a rectangular passive radiator which I switching.Its a step up module.Here we are using it decided to place on the back of the boombox. so that we get a constant 12.6 volt at the amplifier's power input even when the battery voltage goes 5. 3S 12V 18650 10A BMS X 1 below 12.6V http://s.aliexpress.com/M3Y77rIB?fromSns 9. Tweeters X 2:
A BMS (Battery Management System) is very http://s.aliexpress.com/7B7fquIV?fromSns important when connecting rechargeable batteries in series.The BMS makes sure that all the batteries are charged and discharged equally.It makes sure the https://www.aliexpress.com/item/Universal-High-Eff... same amount of current is drawn from all the batteries when in use.A BMS also limits the maximum current The tweeters cover the all high frequency notes in that can be drawn from the battery pack so that the music. Here we are using a piezo electric as well as a cells wont be overloaded.The BMS dosn't have a magnetic silk diaphragm tweeters.I tried different voltage regulator , so its really important that you use combinations and I was most satisfied when I used a 12.6 volt charger when charging the battery pack. both at the same time.Always make sure yoy are using a filter capacitor or a crossover brfore using a tweeter. 6. Frequency Crossover X 2 : http://s.aliexpress.com/jyYB3IRz?fromSns 10. DC Jack(2.1 mm) X 1:
http://s.aliexpress.com/JRj6FZ3a?fromSns A crossover usually has an Inductor (copper coil) of thick wires and a series of capacitors.So a cross over has 1 input and 2 outputs. The inductor blocks the For the charging port high frequencies.The output from the inductor is given to the subwoofers. The capacitor blocks the low 11. Bluetooth Audio Decoder X 1: frequencies .So the high frequency output from the capacitor is given to the tweeters.The tweeters could http://s.aliexpress.com/F3YVrM3I?fromSns blow up if the output from the amplifier is directly connected to the tweeters without the capacitor stage. For getting input from different sources like USB,AUX,FM,Bluetooth ,SD etc 7. 12.6 volt Charger(2.1 mm pin) X 1:. http://s.aliexpress.com/vmIvABb2?fromSns 12. 18650 battery(capacity of your choise) X 3:
http://s.aliexpress.com/r6vIfYzy?fromSns For charging the battery BMS system
DIY HANDBUILT PORTABLE BOOMBOX: Page 4 https://www.aliexpress.com/item/Free-shopping-Keda ...
Our power house.There are 1000s of different manufacturers for 18650 cells . Be sure to get one from a good manufacturers . 18650 cells could get dangerous if it has defects and not charged properly.I have attached the links of two types which I have personally bought and found that its good and safe.
13. DC toggle Switch X 1: http://s.aliexpress.com/B7JFNZbm?fromSns
14. Connecting wires https://www.aliexpress.com/item/ribbon-cable-20-WA. ..
15. 4000uf (or higher) , 16 volt capacitor https://www.aliexpress.com/item/Aluminum-electroly.. .
16. Wood glue
17. Spray Varnish
18. Wood sealer
19. Sand paper
20. 3mm LEDs
21. Thick double sided padding tape
22. All the necessary screws
23. 18 mm plywood sheets.
24. 5mm plywood
25. M3 and M4 nuts and bolts
DIY HANDBUILT PORTABLE BOOMBOX: Page 5 DIY HANDBUILT PORTABLE BOOMBOX: Page 6 DIY HANDBUILT PORTABLE BOOMBOX: Page 7 DIY HANDBUILT PORTABLE BOOMBOX: Page 8 Step 2: TOOLS REQUIRED:-
1. Philips Screw driver
2. Soldering Iron
3. Jig Saw
4. Sand paper
5. File(flat and triangular)
6. Rotory Tool(sanding bit, drilling bit,disc cutting bit,hole cutting or engraving bit)
7. Hot glue gun
8. Scissors
9. Pliers
10. Drill set
Step 3: SPECS:-
1. Total output power : 30 watts
2. 12.6 volt , 2600 mah battery
3. 6 hours of play time (depends on volume)
4. Charging time : 3 hours max
5. Dual Passive Radiators
6. Supports USB, AUX,FM,Bluetooth and SD card
7. Button feature and IR remote
8. Pywood housing and stainless steel handle
9. Neodenium silk diaphrag as well as piezo electric tweeters
10. Superb Bass
DIY HANDBUILT PORTABLE BOOMBOX: Page 9 Step 4: CUTTING OUT THE FRONT PANEL:-
1. The first step is to draw the design on to a sheet of 2. Using a jig saw , cut out this shape from the sheet . 5 mm plywood .The design should be determined Be very careful while doing this as you could easily according to the size and placement of the speakers injure yourself. you are using . In my case, I was using 3 inch speakers , so took the measurements according to 3. File the edges and make it smooth and even. that.
DIY HANDBUILT PORTABLE BOOMBOX: Page 10 DIY HANDBUILT PORTABLE BOOMBOX: Page 11 DIY HANDBUILT PORTABLE BOOMBOX: Page 12 Step 5: CUTTING HOLES ON THE FRONT PANEL:-
1. Draw 2 circles of 3 inch diameter where you want using a hole bit and a drill. to place the speakers. 6. Using a disc cutting bit , cut out the square holes 2. Attach the cutting guide to your rotary tool.Use a for the bluetooth decoder and the Dc switch cutting bit or an engraving bit . I used an engraving bit so that I could cut out the circles slowly and smoothly. 7. Place the speaker on the 3 inch hole and mark the points for drilling holes for the M3 bolts which are 3. Drill a hole somewhere inside the circle near the going to be used for attaching the speakers to the brim . Position the cutting setup through that hole front panel from the other side,then start cutting and move towards the brim. Once you reach the brim, follow the 8. Drill these holes using 3 mm bit. circle. 9. File and smoothene the holes made for the switch 4. Cut out both the 3 inch holes like this. and the decoder using triangular file.
5. 1 inch holes for the tweeters can be drilled out
DIY HANDBUILT PORTABLE BOOMBOX: Page 13 DIY HANDBUILT PORTABLE BOOMBOX: Page 14 DIY HANDBUILT PORTABLE BOOMBOX: Page 15 DIY HANDBUILT PORTABLE BOOMBOX: Page 16 DIY HANDBUILT PORTABLE BOOMBOX: Page 17 DIY HANDBUILT PORTABLE BOOMBOX: Page 18 DIY HANDBUILT PORTABLE BOOMBOX: Page 19 DIY HANDBUILT PORTABLE BOOMBOX: Page 20 Step 6: CUTTING OUT PLYWOOD RINGS FOR THE FRAME:-
1. Place the front panel on a sheet of 18 mm plywood start cutting with the Jig saw and it also helps when and draw the outline cutting curves.
2. Draw the second outline inside the first leaving 8 4. Place the jig saw in one of the holes and start mm gap between the both . This 8 mm is going to be cutting out the ring. Cut the inner outline first and then our wall thickness cut the outer piece off
3. Drill four 1 inch holes on each corner touching the 5. Similarly cut out 3 such rings. inner outline . This is done so that we get a point to
DIY HANDBUILT PORTABLE BOOMBOX: Page 21 DIY HANDBUILT PORTABLE BOOMBOX: Page 22 DIY HANDBUILT PORTABLE BOOMBOX: Page 23 DIY HANDBUILT PORTABLE BOOMBOX: Page 24 Step 7: LAYERING THE PLYWOOD RINGS:-
1. Applying wood glue on both the surfaces stick all 3. Wood glues work best when a load is applied the rings together as seen in the pictures.Wipe off the during the drying period . People usually do this using excess glue using a cloth. clamps , but since I didn't have any I used a huge bucket filled with water to act as the compressing 2. You don't have to worry if the rings are not aligning load. perfectly as we will sand everything down to perfection in the following steps. 4. Let the glue dry overnight.
DIY HANDBUILT PORTABLE BOOMBOX: Page 25 DIY HANDBUILT PORTABLE BOOMBOX: Page 26 Step 8: SMOOTHENING THE FRAME:-
1. All the major imperfections are sanded down easily using the rotary tool and a sanding bit
2. The remaining sanding was done using different grades of sand paper by hand moving from rough to super smooth sand paper
3. Sand it until you are satisfies with the finish.
DIY HANDBUILT PORTABLE BOOMBOX: Page 27 DIY HANDBUILT PORTABLE BOOMBOX: Page 28 DIY HANDBUILT PORTABLE BOOMBOX: Page 29 DIY HANDBUILT PORTABLE BOOMBOX: Page 30 Step 9: MAKING SURE THE FRAME WILL BE AIRTIGHT:-
For the passive radiators to function properly , it is really important that the enclosure is completely airtight.
1. Coat the inside of the frame with 3 layers of wood glue.
2. There are usually small holes on the cross section of plywoods . If such holes are present on your frame, fill them with wood glue or some other sealant like Mseal , let it dry , and then sand off the excess.
DIY HANDBUILT PORTABLE BOOMBOX: Page 31 DIY HANDBUILT PORTABLE BOOMBOX: Page 32 Step 10: PREPARING THE BACK PANEL:-
1. Place the frame on a sheet of 5 mm plywood or files. laminated MDF. 5. Drill a hole for the DC charging jack. 2. Trace out the outline onto the sheet. 6. Drill screw holes around the panel for attaching it to 3. Cut out the back panel using a jig saw the same the frame. way we did with the front panel. 7. Counter sink these holes using a larger bit so that 4. Cut out the holes for the passive radiators using a the screw head would fit flat with the surface jig saw and make them perfect and smooth using
DIY HANDBUILT PORTABLE BOOMBOX: Page 33 DIY HANDBUILT PORTABLE BOOMBOX: Page 34 DIY HANDBUILT PORTABLE BOOMBOX: Page 35 DIY HANDBUILT PORTABLE BOOMBOX: Page 36 Step 11: THE HANDLE:-
Here I used a small stainless steel cupboard door handle.
1. Holes for the handle are drilled on to the middle ring of the frame
2. I used a rectangular piece of MDF inside so that the load would be equally distributed over all 3 layers instead of just one.
3. Tighten the bolts with steel washers in between.
DIY HANDBUILT PORTABLE BOOMBOX: Page 37 DIY HANDBUILT PORTABLE BOOMBOX: Page 38 Step 12: ATTACHING THE COMPONENTS TO THE FRONT PANEL:-
1. The first thing I attached was the power LED with a attached it to the front panel. 10 k resistor 4. Both the tweeters were glued on to prevent nuts 2. Then I attached the audio decoder and the power and bolts switch followed by speakers. 5. All the areas where there is a chance of air leak 3. I decided to use only the high pass section of the was covered with hot glue. frequency cross over . So I removed that section and
DIY HANDBUILT PORTABLE BOOMBOX: Page 39 DIY HANDBUILT PORTABLE BOOMBOX: Page 40 DIY HANDBUILT PORTABLE BOOMBOX: Page 41 DIY HANDBUILT PORTABLE BOOMBOX: Page 42 DIY HANDBUILT PORTABLE BOOMBOX: Page 43 DIY HANDBUILT PORTABLE BOOMBOX: Page 44 Step 13: ATTACHING BACK PANEL TO THE FRAME:-
1. Matching holes were also drilled to the frame . These holes should be slightly smaller in width than the screw you are planning to use.
2. A layer of thick double sided tape is applied on the frame as seen in the picture and the excess is cut off using a razor.This layer acts as a padding which helps in making the enclosure airtight.
3. Without removing the yellow film , the back panel is screwed on to the frame.
DIY HANDBUILT PORTABLE BOOMBOX: Page 45 DIY HANDBUILT PORTABLE BOOMBOX: Page 46 DIY HANDBUILT PORTABLE BOOMBOX: Page 47 DIY HANDBUILT PORTABLE BOOMBOX: Page 48 Step 14: PREPARING THE BATTERY PACK:-
1. Make sure all 3 cells have the same voltage
2. Connect the cells to the BMS according to the circuit diagram.
3. The BMS will reset and start functioning for the first time only after the charger is connected to the output.
DIY HANDBUILT PORTABLE BOOMBOX: Page 49 DIY HANDBUILT PORTABLE BOOMBOX: Page 50 Step 15: ADJUSTING THE BUCK AND BOOST CONVERTER:-
1. Connect the input of the buck and boost converter to the output of the Battery pack .(Be careful with the polarity)
2. Connect the output of the boost converter to the multimeter and turn the golden screw until the output voltage shows 12.6 volts.
3. Similarly connect the output of the buck converter to the multimeter and turn the small potentiometer until the output voltage shows 5 volts.
Step 16: THE CIRCUIT:-
DIY HANDBUILT PORTABLE BOOMBOX: Page 51 Step 17: COMPONENT PLACEMENT AND CONNECTION:-
1. The switch and the DC jack is connected to the are pressed on and stuck in its required position. back panel. 4. The remaining components are also placed using 2. A 4700 uf capacitor is connected to the output of this glue and connected to each other using wires the boost converter. according to the circuit diagram.
3. Rubber based adhesive(fevi bond) is applied on 5. Hot glue is also applied just as insurance. the brim of the passive radiators as well as around its cutout hole . After waiting for 10 min , the radiators
DIY HANDBUILT PORTABLE BOOMBOX: Page 52 DIY HANDBUILT PORTABLE BOOMBOX: Page 53 DIY HANDBUILT PORTABLE BOOMBOX: Page 54 DIY HANDBUILT PORTABLE BOOMBOX: Page 55 DIY HANDBUILT PORTABLE BOOMBOX: Page 56 Step 18: CLOSING UP THE ENCLOSURE:-
1. All the wires from the front panel are connected to their respective points on the amplifier and and power supply according to the circuit diagram.
2. Wood glue is applied ,the frame and the front panel is joined and a load is placed on top as seen in the pictures. (be careful not to damage the speakers while doing this)
DIY HANDBUILT PORTABLE BOOMBOX: Page 57 DIY HANDBUILT PORTABLE BOOMBOX: Page 58 Step 19: FINAL FINISHING:-
1. Cover the whole front panel , Back panel and the 5. Hang the boombox by its handle in an open area steel handle using plastic tape and news paper. and start spraying the gloss varnish evenly without forming drops. Apply 3 coats of varnish. 2. Sand the edges and the corners of the front and rear panel so that it aligns flat with the main frame. 6. Add 4 rubber foot so that the speaker wont move around due to vibration while playing music. 3. Do the final sanding using smooth sand paper. AND THAT'S IT , YOU ARE DONE :-) 4. Coat the frame with 2 layers of wood sealer and sand again.This is done to prevent the wood from absorbing the varnish when its sprayed on.
DIY HANDBUILT PORTABLE BOOMBOX: Page 59 DIY HANDBUILT PORTABLE BOOMBOX: Page 60 DIY HANDBUILT PORTABLE BOOMBOX: Page 61 DIY HANDBUILT PORTABLE BOOMBOX: Page 62 Step 20: MORE PICTURES:-
I hope I wrote the instructions clearly . Do let me If you guys like my instructable pleas do vote for me know your opinions about my boombox on the in The Audio Contest comments section .I had to build the boombox using the only tools I had , so some of my methods of THANKYOU :-) working with plywood wont be right, pleas do let me know where I have to improve. Meanwhile if anyone has any doubts with the built feel free to ask me .
In the supply list the tweeters are the same but in the assembly photos they look different. Why is that? This thing is really cool and I want one! Thanks. I just swapped one of the tweeters with a piezoelectric tweeter . The other one is the same as in the supply list . I have mentioned why I did this in the introduction and also among one of the comments . The different tweeter I used is just a low cost automobile tweeter which is awailable almost in any automobile accessories shop . So you won't have any trouble finding those Thankyou:)
DIY HANDBUILT PORTABLE BOOMBOX: Page 63 A masterpiece in itself great!!!!! Thankyou so much :-)
I like the way it looks, also interesting to see how you build it, thanks!
Thankyou :-)
Just curious, what's the total amp draw off the batteries and how much run time do you get? Not sure about the current drawn . But I am getting 4 to 6 hours of play time depending upon the type of music and volume. This looks really good. Thank you for sharing :-) Thankyou:-)
Nice design and execution. I see you used Aliexpress for most of your parts including the speakers. Have you ever looked at Parts Express? The sell tons of quality speakers with all the data of each speaker one could ask for. I built shop speakers using their products and they sound amazing. Your wood box enclosure looks very nice. Have you disconnected one of the tweeters at a time to see if you could hear any difference? Just wondering. Thanks I am from India , so I guess the parts would get really expensive once the shipping charges are added if I order stuff through parts express
And yup , first I used 2 magnetic tweeters , but I was not satisfied.So before finally closing everything up ,I just swapped one of the magnetic tweeter with a piezoelectric one . And There was a huge difference . Usually magnetic tweeters are the best , but I don't know what happened in this case , I guess the ones I had was not of good quality.
DIY HANDBUILT PORTABLE BOOMBOX: Page 64