Introduction: Make a Speaker and Amplifier Without Complicated Electonics

Picture of Make a Speaker and Amplifier Without Complicated Electonics
For a while now I have wanted to make an audio amplifier, but I haven't really had any good opportunities or means to the end. When I found out about the Mono Audio Amp Breakout from Sparkfun, I started to get exited. Its perfect for what I wanted. It's effective and soldering in the right wire is no more difficult than setting up a regular sound system. Not to mention how great it looks in that laser cut mirrored acrylic case. Enough Talk. What does it sound like?

Step 1: Materials and Tools

Picture of Materials and Tools

1 USB  micro jack
2 Potentiometers, not logarithmic, mine are logarithmic and there is a narrow range of control now
2 Mono Audio Amp Breakout Boards
1 Switch
1 3.5 mm jack
8 bolts and nuts of appropriate sizes

Tools(This is what I used, you could probably get away with less)
Soldering Iron
JB weld
Sand paper
Helping hands are practically a necessity, but if you are dextrus enough you might slide by without them
Chisel and hammer, Theses come in really handy when I find out my laser cut design wast good enough, which is often.

Step 2: Design.

Picture of Design.

There is a great Google Sketchup Plugin by flightsofideas which makes an SVG file from 3D designs in Google sketchup. You can find the Instructable here
Anyway, I designed how I wanted the box to be using sketchup and then transferred the faces to an SVG file and put them on the Ponoko P2 laser cutting template.

Step 3: Prepare the Laser Cut Acrylic

Picture of Prepare the Laser Cut Acrylic

I got it the acrylic laser cut at Ponoko. After it came I removed it from its protective layers and tested them for fit.

Step 4: Soldering Most of It

Picture of Soldering Most of It

I connect a wire running from the ground wire on the USB jack to the ground pins of the mono Amp and the negative pin of the switch. Don't forget to put the switch through the hole before soldering.
Next I connected the positive voltage to the opposite end of switch.
I then connected the potentiometers to the appropriate holes on the mono amps, that is either edge pin to either edge hole, and the middle pin to the middle hole.
I connected the pins of the audio jack to the appropriated pins of the mono amps. That is the pin the pin with the hole is the negative wire, and the two pins that comes up and bends are positive (look at the pictures for help). Connect the different positive pins to different mono amps but connect the negative pin to both.
I fed the speaker wires through both of the holes, and then soldered them into the audio out pins.
Makes sure everything is connected and makes sense.
We are ready to test!

Step 5: Test 1

Picture of Test 1
Check everything one more time, than plug the USB into a computer USB port and the speaker into a speaker output. Look for a headphones output. Then play some audio!

Step 6: Shrinkify

Picture of Shrinkify

And now, because I have A LOT of extra wire, I needed to get less of it to fit it inside the box, so I cut the wire in two places, striped it, twisted it together and soldered. Then I covered it with electrical tape to keep it from shorting out. Repeat for all the long wires.

Step 7: Second Test

And now, another test of the speakers before it it all put together.

Step 8: Adjust and Glue

Picture of Adjust and Glue

There are little pins on the potentiometers that keep them from spinning behind the acrylic. I put them into the appropriate laser cut holes and where the pin hit the acrylic, I made a mark with a sharpie. Then I drilled part of the way into the acrylic from the back, and tested it to make sure it fit.
Then I cut some necessary slots for the USB, and drilled partway from the front into the audio jack hole, this is for the little provided bolt. Be sure to drill in far enough or else the jack wont go in all the way, but not to far, or else it is much harder to affix to the acrylic.
Now start gluing! only glue the USB, audio jack and on/off jack. I used JB weld for all the parts going into the hole, and then I used hot glue for putting the box together. When there is one side left, put glue on the joints and push them together. After the glue dries, use a hobby knife to clean it up. When both boxes are glued, put glue on the side of the smaller box with the hole and push it onto the bigger box so that the holes of the speaker wires line up.

Step 9: Make It Look Nice.

Picture of Make It Look Nice.

If the light on the switch doesn't work 100 percent of the time (like with mine) you can put Sugru on the switch. Changes are you probably have some extra Sugru. May I suggest mending your 100% penguin Sugru phone case, or a wire holder. 

Now time for a cable holder. Make some holes at each corner, and a trapezoid piece from the top. Then cut some slits into the holes. look at the pictures to see how to use it.

Step 10: Done!

Picture of Done!
now enjoy the marvelous awesomeness of the speaker!


Fahad Nadeem (author)2015-01-04

can you add more watts and speakers.but the ohms will be the same right.8ohms

i want to 5 speakers with bass

can i build them

Sameer Don (author)Fahad Nadeem2015-10-31

yes Fahad you can make but u can make your amp with lm386 ic and it gives 10w power at 12v dc. circuit diagram build yourr own

manuelg93 (author)Sameer Don2016-08-20

I got a tda 7784 can i make an amp

Of course u can build it. But u have to use high powered amplifier and it is better to use stereo amplifier to mono..

manuelg93 (author)2016-08-20

I got tda 7784 can i make an amp for my phone

psycho8714 (author)2016-05-10

how to make the board, i have speakers taken from an old radio (2big and 2 small radio has treble,bass,and one other thing) so how can i make a speaker set out of it which i can connect my mobile

kimdats (author)2015-12-07

how about if i dont have a matherboard

ZarnabQ (author)2015-11-28

Where did you buy that mono amp breakout board from because i have searched many sites online and cant seem to find the same one or one that has as many inputs/outputs as yours

abdoulsani (author)2015-06-03

wow! nice one dude.

coolbestman1 made it! (author)2015-02-15

I had made the amplifier with stereo board which makes me easier to control the sound for the both the speakers at once. The acrylic housing is good. the stuffs i used are 4 ohm speakers and plywood for housing. even then it looks awesome...

Wrynsky169 (author)2014-09-08

Hello, I was wondering if you had a link to the sketch-up design, or details on how to make it. I will get the plugin for Ponoko, but I don't know how to recreate the design.

Nice 'ible, I'm using it as inspiration for a school project!

Ploae Ionut (author)2014-02-20

too complicated!!!!!

nerd7473 (author)2014-02-13

I need help, how do I wire this to two AA batteries and a headphone jack to go to a 3" 2.5W speaker?

I am wanting to make a mini mono amp with input for phone or guitar.

nerd7473 (author)nerd74732014-02-13

The link is to a stereo 2.8W Amplifier breakout

GenAap (author)nerd74732014-02-13

Adafruit has a great tutorial for this.

Here is the page you are probably looking for.

Happy Making!

nerd7473 (author)GenAap2014-02-13

thanks for the link I will buy this soon

doosantech (author)2014-01-19

BRAVO.... I've been wanting to build one for my car for a few years now but I lack the knowledge of electronic components to do so... hints this question I'm about to a I'm trying to add a remote bass knob to my amp that was soupossed to just plug in via a phone jack...but my amp lacks the jack... I want to replace the potentiometer on the amp with a phone jack, any chance you could be of any assistance if you have the time?

purple people (author)2013-06-18

for future reference, you would get more bass and better sound out of it if you cut a vent about 1-1.5" circle in the back.

GenAap (author)purple people2013-06-18

Thanks! I'll remember that.

Fozzibehr (author)2013-03-30

I Like Your instructable, but I was wondering if there was something like this for a higher powered boombox?

wdsims63 (author)2013-02-21

Next time, grab some heat shrink tubing and slip it on the wire before you put it back together. Looks better and won't slip off accidentally.

GenAap (author)wdsims632013-02-21

If only I had the money to buy heat shrink and a heat gun. :'(
Maybe someday...

smoak (author)GenAap2013-03-15

Heat shrink isn't that much and a quick passby with a lighter and you can shrink the tube. Or if you have a variable temperature soldering iron use that at the lowest possible heat to shrink it.

GenAap (author)smoak2013-03-19

I was actually just watching some Adafruit videos and saw them use the back of the soldering iron. Brilliant! I'm definitely going to buy some as soon as I can get to the store.

marksstudio (author)2013-02-21

Outstanding tutorial! Timely as well. I am building small speakers for a workstation as I have some perfectly suited drivers laying around. Since viewing your excellent tutorial, I am contemplating a few changes to the plan; Why not attempt an amp?
Thanks and regards.

GenAap (author)marksstudio2013-02-22

This is and amp, as far as my understanding of an amp goes (quite signal goes in, less quite signal comes out), but there are certainly better (and louder) options out there that offer way more control over what comes out of them. But my goal was to amplify speakers for a laptop, so anything that required more than the 5 volts would not have worked out well for this project.

smoak (author)GenAap2013-03-15

Firstly, I think him saying "I am contemplating a few changes to the plan; Why not attempt an amp?" was about his plan. Since he already had a plan to do basically this but without an amp, you're 'ible made him want to add an amp.

Secondly, I decided the other night I was going to make an old set of computer speakers USB instead of wall-wart. With one of the speakers having the amp inside and the other just the speaker (as it already was done that way). So this made me think, why not move the amp to a separate box and then have to plug the speakers into the amp, that way I can add more sockets for speakers (maybe boosting the amp a little prior) and can have as few or as many (within reason) speakers as I want! So thanks for the 'ible. Gave me some ideas on how to change things about.

techhobbit (author)2013-03-09

You are a genius! This is a beautiful piece; the extra care in size comparisons brought tears to my eyes. The combination of SparkFun, a SketchUp designed/Ponoko cut, morror finished acrylic case, and Sugru, puts this ible in the top 1%! (IMHO)
And, its a well done, and thorough instructable! Great job!

tseay (author)2013-02-22

I really like your style. And here is a little suggestion. All that nice plastic will direct LED lights to the edge giving a nice glow on those awesome laser cuts. It will take a bit more power, but a LED glow, would give your project more awe points.

GenAap (author)tseay2013-02-22

I wish that would happen, but to get the mirrored effect on this acrylic it has an opaque backing on it. But I like that idea a lot. Diffused acrylic plus the LED's would really make this amp super awesome. I'll remember that for a future project.

Thanks for the complements!

Trickynekro (author)2013-02-21

Personally I would refrain from using the USB as a means of power, unless it´s a must like these being laptop speakers or something like this, I would also have included a power jack for a cheap switching power supply, pretty small these days and light, not making themselves a problem carrying around. So if the USB power supply is a must you might think of adding an electrolytic capacitor at the input rail, helps with the bass frequencies.
Apart from that that´s a really nice project, I love the case! Keep it up mate!

GenAap (author)Trickynekro2013-02-22

Yes, this is for a laptop. Naturally I would have chosen better amps if I didn't need this to be small(ish) and powered solely off a laptop.

cody305 (author)2013-02-21

This looks very useful and easy to do! Does this one (or do you know of one) that also has a "tone" or "bass and treble" controls? On a related note, I have been wanting to make a preamp for my main audio amp that has AVC (automatic volume control) to help limit the volume excursions on movies or music that can really overwhelm folks with delicate hearing. Do you know where to get something like that? Thanks for a great "ible"

GenAap (author)cody3052013-02-22

No, this one only has volume control. From what I've seen on his web site (here) you would be better off talking to this guy for almost anything dealing with audio.

wdsims63 (author)2013-02-21

So, you have a volume knob for each channel? Did you know that you can get stereo volume knobs?
I like the look of those knobs though.

GenAap (author)wdsims632013-02-22

Yes, for the knob for each channel, and no to the stereo volume knobs, but thanks for sharing. Looking back I really should have done more research before starting oh the project. Oh well, at least it works. That's more than I could ask for for many of the other projects.

GenAap (author)2013-02-22

That's nice! Do they sell the connectors that go with it, or would one just solder wires onto the pins?

DustySeven7 (author)2013-02-21

or you can crazy and use TDA 2050 chips and build completly from the ground up

GenAap (author)DustySeven72013-02-22

That kind of defeats the purpose of the "without complicated electronics" part of this instructable, which was kind of the main purpose here. But the plus side of your method is I would get more control over my the amp, which for some people is a must. For anyone else reading this comment, there is a great tutorial on making an audio amp with the TDA 2050 chips here.

nerd7473 (author)2013-02-19

did you get all of the boards from sparkfun?

GenAap (author)nerd74732013-02-19

Yes indeed!

nerd7473 (author)GenAap2013-02-22

that is cool

MartyMart (author)2013-02-21

Nice ible! However, this will save you time and money. DealExtreme has a DUAL channel 3 x 3 watt amp for $3 :) It even has the wire leads w/ plugs attached! See here:

Mini Digital 3W+3W Amplifier Module Board

They also have some sweet tiny 3 watt speakers

I just built a guitar amp with these and let me tell you they are awesome! 

GenAap (author)MartyMart2013-02-21

Those are amazing! If I ever do this again I will definitely be using those.
This is the reason I love instructables. Those with another way are always happy to share. 

MartyMart (author)GenAap2013-02-21

I hear you bro! This site has fueled my fire too! I've done a lot of research on battery powered amps and somehow stumbled on that DX 3x3. Good find to say the least.

That said, nothing wrong with going old school and building one!!!

netgrazer (author)2013-02-21

Nice 'ible!
One remark though:
For size comparison neither a "270 shell", or a Sugru sachet, or that coin thingie make a lot of sense to people who have never seen them. A match or a CD/DVD/BR for example are ubiquitous in all cultures and will probably still be around in a couple of years. A ruler (with both imperial and metric? :) ) works well, too.

GenAap (author)netgrazer2013-02-21

Its about the size (looking at the Sparkfun website) of a US quarter dollar, which is (looking at Wikipedia) about 24 mm (that is a little under an inch) in diameter and (again Wikipedia) 1.7 mm in thickness. If you aren't close to a ruler, or don't feel like searching for one online, the mono amp is about half the length of a AA battery, 2 times bigger than minimal wavelength of the super high frequency band and about the length of a microwave (that is the electromagnetic wave, not the appliance). It takes light roughly 80 picoseconds (that is 1/12500000000 of a second) for light to travel the length of the mono amp in a vacuum, naturally not in Bose-Einstein condensate, in which it takes about 1413/1000000 seconds, which is sufficiently slower. By the way I sure hope the speed of light stays constant from today to tomorrow and from society to society. I don't want to know what would happen if it suddenly changed.
That second link to society is mouthwatering don't you think?
Enjoy :)

P.S. As a matter of fact I do like Wikipedia. I use it all the time. AndasyoucanprobablytellIalsolikeHyperlinks.

GenAap (author)GenAap2013-02-21

Sorry. The second link to society was suppose to be this and the smiley face this.

Insonicbloom (author)2013-02-21

there are some good stripboard layouts for amps/stereo amps and a lot of other stuff here

GenAap (author)Insonicbloom2013-02-21

Oooo. Nice. I'm eyeing that 9v battery charger and devils triangle drone synth.

About This Instructable




Bio: I enjoy electronics and like to build things through whatever medium I need to in order to get to an end.
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