DIY Amplified Speakers for your MP3 player

There are quite a few instructables out there on making your own speakers for your mp3 player... and most of them don't use an amplifier! Without an amplifier you will barely be able to hear the music coming out of the speakers.

Here I will show you how to make your own stero speakers with amplification!

Video here:
http://www.youtube.com/watch?v=C4d4_k0mwWo

Step 1 Gather materials

Here are the materials used:

Cardboard box - used as speaker housing, you can choose something more elegant
Drill bits - used to drill some holes
Two speakers - I chose a pair of generic 8 ohm ones lying around
Soldering equipment
Hot glue

Here are the parts for the amplifier circuit:
1x protoboard
1x TDA2822M amplifier IC
2x 100uF capacitors
2x 470uF capacitors
2x 0.1uF capacitors
2x10K ohm resistors
2x 4.7 ohm resistors (I used 3.3K and it worked fine)
IC socket
Misc. connectors

Comments

[argil]

if it is ok if i plug this amp with a 220v?

[ivanjacob]

wutlol?!

[Glenn781]

no it runs on 18 to 4.8 v

[Elitekilla117]

Ok, I need help from someone with experience. I bought a cheap PA system with a speaker on Ebay for $25 dollars. I got it a month later from China. It's pretty cheap. I like the simplicity and cost efficiency, but hate the loudness. They claim it's rated at 60 Watts and 115 dB but I find that hard to believe. So, I walk nonchalantly into Radioshack to purchase myself a 50W Powerhorn. Man this thing can get loud! But, only if I have a good amp. I want my PA system on my car to be loud, not as loud as a Police or Firetruck siren, but pretty close.

From my research, I need to get somewhere around 110 dB. I used the amp off the crappy Chinese speaker and hooked it up to the new powerhorn. It worked fine but still not loud enough. The new powerhorn from Radioshack was better than the Chinese speaker. But I still need a better amp.

On the box, it says it's a 25W/ 50W MAX 8 ohm speaker with a output of 102 dB. It needs a 8-50W RMS amp. Me being broke, but knowing a good amount about electronics, I thought I'd give myself a shot at building an amp. Unfortunately, Speakers are the one field I am terrible at. But I don't have a lot of money to spend to buy a nice amp. So I ask anyone with experience or an idea to please advise. Thank you

**PLEASE NOTE, I AM NOT ONE OF THOSE MORONS THAT USE A PA SYSTEM TO PRETEND TO BE A POLICE OFFICER. IN FACT I PLAN ON BEING A POLICE OFFICER IN THE FUTURE. I DO NOT USE THIS DESTRUCTIVELY. PLEASE KEEP THIS IN MIND.

[techboy411]

hasnainahmed101 is right¸

[techboy411]

OP-AMPS,COOL

[ajervis]

will the amp still play clear if i dt use a 10k on one of the input? BTW i hooked up everything right and the quality was terrible...

[ajervis]

how i make the input go to one audio jack since they have 2 input and output parts for the amp.

[Blak Wolf]

The triangles are just parts inside the IC right?

[ajervis]

the bold lines are ground, triangles belong to the IC

[Blak Wolf]

and do the thick black lines at the ends there mean they go to ground?

[Blak Wolf]

This may be a totally dumb question, but what are the triangles in the diagram representative of?

[Reki3]

Please excuse me for being s bit uninformed on this, but what do you mean by 'RL'? What resistors can we put in, and is it still necessary with small voltages?

[kostya]

I have built a few amplifiers around TDA2822M and can say that this chip is an inexpensive option for handheld devices. The schematic you chose is used for earphones (32 Ohm) and isn't optimal for speakers. I would recommend to use 2 chips (bridge schematic), each drives a speaker(8 Ohm). In this case you will get over 1 W in each channel with 9V adapter. To obtain stereo effect place speakers on the sides of the box.

[xaenon]

I just wanted to point out that if you want to get an amplifier module already assembled and ready to work with approx 6-9V, you could buy a set of ultra-cheapie computer speakers. Many of the ultra-cheapies use this very same amplifier, right down to the TDA2822 integrated circuit. In addition, they'll come with an AC adapter, but most of the amp boards in cheapie computer speakers have a built-in bridge rectifier assembly, and it isn't hard to adapt the circuit for DC power.

It might seem counter productive to hack up a set of computer speakers to make another set of speakers, but one of the greatest limitations of cheapie computer speakers is their chintzy little drivers and tiny enclosures. Better speakers in an acoustically-better enclosure goes a long way toward better sound, even with a micro-amp like the TDA2822.

[SpEcIeS8472]

Could you post a pic of your schematic?

[hasnainahmed101]

nice work !!

[dasimpson1981]

just built this amp my self with a few changes.
i changed the 470uf and 100uf caps to 220uf caps
just got to build another 2 then so i have a 6 channel ampf for my 5.1 set up

[talha91]

Hi,

I am just a Beginner with this from Pakistan so the thing is that I cant understand this one step 2... The graphical Diagram of the circuit can u just make it rough like by Hand so I can better understand this step...

I know i can manage to understand it latter on by reading some articles on Google about electronic Circuits but if u can just share one more picture using pen and paper without straight lines....

[bmxlive]

hi, at this step are you trying to say that i can build the same circuit but with other IC amp chip? i saw in differents instructables that every different amp circuit has differents components with some exeption like 0.1 uF capacitor. I would like to use a LMN386 that i can find in my local store but im not shure if i choose to use others components like this structables it will work. I hope you can help me

[RazorConcepts]

This schematic won't work with the lm386, you will have to use the schematic from the lm386 datasheet.

[zachzach]

i need more specific instructions on what to connect to the IC, and where did you get your IC (TDA2822M)

[RazorConcepts]

I got the IC as a free sample from the manufacturer.

Here is the datasheet:
http://www.st.com/stonline/products/literature/ds/1464.pdf

[zachzach]

who's the manufacturer and how could i get a free sample?

[chriskarr]

You could get a free sample by becoming an R&D department manager for a major corporation. It is illegal to sample from companies when you claim to be something you're not - i.e. an interested company, or student when you are not the one you said - and to sell a sample (whether as a part of a larger end-circuit, or as a single component) or barter with it, since it is meant for research and is meant to be used and discarded.

[Deus Tempestas]

It is not illegal for a company to send you a free sample, I have requested and was sent everything from IC sockets, op amps, audio amps, even three axis acceleration ICs. On every request for I stated I was a hobbyist and wanted the samples for personal use. Of the 30 odd samples I've requested, only 2 were not granted, one for LCD switches, the rep said they were too expensive at the time for non-comercial requests. The other was denied because I did not have a .com email address. If you are honest and polite you should have no problems getting free samples. Hobbyist have created many inovative uses for products the manufactures never thought of, opening new markets for existing products. A Win-Win for both companies and Hobbyists.

[Ar4]

Could you tell me where are some class AB amplifier ICs available for sampling. I know NS, STmicroelectronics and Texas Instruments, but these ones doesn't suits for me. I would like to make some 50W+ amp

[Da Nugesta]

good instructable, but u got one of them cheapo knock off itouches

[RazorConcepts]

For $40 its not a bad deal! Radio, voice recorder, touchscreen, camera with pics and video, text viewer, etc etc. I am not really the person to spend over $150 on an ipod touch when a $40 thing works pretty well.

[zack247]

where can i get one of those! it sounds a lot better than a palm zire 31 for a mp3 player

[Da Nugesta]

good point! see ya

[odysseusesperson]

 i just wanna find  the amp on my radio to try to plug the  the wires from my jack to play my ipod louder

[tinkertoyboy]

what do u conect to the end of the 100uf capasitors

[1nstru]

actually, a bass reflex system with a chassis this small might not be the most feasable choice. when you make a new case to replace the cardboard one - probably from wood - try it out as an airtight chassis first. it might get you way better bass response. there are battery compartments available that are airtight on one side and have a flap on the other to change the batteries. double sided foam adhesive tape is ideal to seal the joints for the bat. case and the speakers. also, one large speaker instead of two small ones will give you a better boom for the buck (read: bass audio for amp output power ;)

[Quercus austrina]

I agree with 1nstru, you won't need a bass reflex design for those speakers. Bass reflex is for speakers that can move large volumes of air. A Sealed Box would be the best for those little speakers. How big are they, 2"?

Actually, the cardboard acts as a resonant surface that enhances the bass output, and in your case is probably the best you can do for those speakers. Maybe in the future you could build a small wooden box and have a cardboard panel on the front, at least as big as the 2 speakers when mounted.

Good build, hope it performed well during camp.

Qa

[SpEcIeS8472]

Hi, sure you remember me from the little problem with the parts list ;) Well, in the meantime I got my parts and found time to build it. And I really was surprised. It works FANTASTIC! Thanks for this great instructable! :D

[bo-jangles]

would this amp be okay for a: •400 Watt Total Pick Power Handling (200 Watt Each) •Impedance: 4 ohms Each

[qnzfinest]

question, i have two speakers with an impedance of 8ohms and a maximum input of 60 watts. Can i use these speakers for this circuit????

[RazorConcepts]

Yes they will be fine, although for a better sound look in the datasheet for the proper circuit as a previous commenter has posted.

[zachzach]

woohoo! yes! i was amazed when i plugged in my mp3, hit the switch, and heard music! :). if i shift the circuit board i get some serious static but i figure its just two wires that bump each other, hopefully easy to fix. thanks for the instructions!