Build Electronic Circuits

Electronics explained in a simple way

The Simplest Amplifier Circuit Diagram

By 130 Comments

I have been looking for a good stereo amplifier circuit diagram for a long time. I am not a HiFi geek, I just wanted to build a simple stereo amplifier that could drive some speakers for my desktop computer.

stereo-amplifier-board-layout

All the schematic diagrams that I could find seemed to involve lots of hard-to-find components or you had to use it together with a pre-amplifier or some other amplifier stage. It was always something that made me hesitate.

But recently I found this awesome little chip called TEA2025! You only need a few capacitors to make a decent stereo amplifier out of it. It is so simple to build that I put it together on a strip board in just a few hours.

2.5W * 2 Stereo Amplifier

The amplifier circuit diagram shows a 2.5W * 2 stereo amplifier. You can also make a 5W mono amplifier out of it. (Check out the TEA2025 datasheet for more information on that)

Stereo Amplifier Circuit Board

On the input side, you should use a dual potentiometer. A dual potmeter allows you to connect both left and right channel on one potentiometer.

This amplifier is great to use together with some speakers to get sound on your desktop computer. I am thinking of putting one in my kitchen and in my bathroom also. Then maybe hook them up to my home network and stream music from a server =) There are many possibilities when you can make such a cheap amplifier.

Amplifier circuit diagram and parts list

A Stereo Amplifier Circuit Diagram

Parts list

Part Value Description
C1 100µF POLARIZED CAPACITOR
C2 100µF POLARIZED CAPACITOR
C3 100µF POLARIZED CAPACITOR
C4 100µF POLARIZED CAPACITOR
C5 100µF POLARIZED CAPACITOR
C6 470µF POLARIZED CAPACITOR
C7 100µF POLARIZED CAPACITOR
C8 470µF POLARIZED CAPACITOR
C9 0.22µF NON-POLARIZED CAPACITOR
C10 0.22µF NON-POLARIZED CAPACITOR
C11 0.15µF NON-POLARIZED CAPACITOR
C12 0.15µF NON-POLARIZED CAPACITOR
TEA2025 TEA2025B Amplifier chip
SPKR1 4-8 Ohm speaker
SPKR2 4-8 Ohm speaker
R1+R2 10K DUAL Potentiometer

Total cost of the components (excluding speakers) is about $9. The most expensive component is the potentiometer (about $3-4).

Download Eagle schematics and board layout

Here is the schematics (Eagle), PCB board layout (Eagle) and Gerber files. This board was made to comply with the design rules of Seeed Studio (May 2013).

Stereo-Amplifier-TEA2025-(Eagle)

How Can I Help You?

I want more people to build better and cooler projects. Everyone can improve even if they are complete beginners or have built many circuits from before.

If you love building things with electronics (or would love to), check out Ohmify.

Return from Amplifier Circuit Diagram to Circuit Ideas

Reader Interactions

Comments

  1. Hello Oyvind,
    Thanks for this useful post. i tried this single chip stereo amp. and it worked. but the problem I faced is there is lots of noise also. first i thought it could be a problem with speaker I used (i got my speakers from toy cars,they lied in the said resistance range), so I moved to market available speakers. but the problem persist. Can u suggest me some solution to get get the rid of this noise. any help will be appreciated.
    Thanks and KEEP SOLDERING :)

    Reply

    • Hey Ravi!

      Cool to hear that you made the circuit =)

      If the input signal is too high, you will get clipping on the output. This will make the sound noisy.

      So first, check if you have the noise problem when the volume is turned down: (R1+R2) pot turned to a high resistance value.

      Cheers!
      Oyvind

      Reply

      • Thanks for your quick reply,
        I tried your suggested solution and yes the noise is still present at lower volumes.
        And then just for experiment I used higher range speakers(~15 ohm , 5 watt), and the problem was gone :).
        but i also doubt that using these higher higher range speakers ,in a continuous run, the circuit might get damaged. Right?
        And one more thing , i think i should add, I am using USB power supply. As I want to make it completely portable.
        Thanks. :)

        Reply

        • No it shouldn’t be a problem to use higher Ohm speakers. And higher Watt-rating of the speaker just means it can handle more power.

          Maybe your old speakers just had too low Watt-rating…

          Anyway, great that you got it working! =)

          Cheers!
          Oyvind

          Reply

        • That’s the issue. The IC is probably running out of power. Buy a tablet power supply (5V 2A, for fast charging) and check current consumption with a multimeter. Probably the USB port isn’t providing enough current (check if your motherboard has a port with a higher current limit, since most ports are limited to 300-500 mA). Or buy a 9V rechargeable battery (raising the voltage to get the same power from the supply will give you less current consumption, which is nice running on batteries).

          Reply

    • Check the input stage for bad solder joints (can act as diodes hence radio noise). Try a aluminum foil shield to check for external signals that show up as noise. Have an oscilloscope? Check for oscillations in your component layout etc.
      Good luck!

      Reply

  3. Hey, thanks for the great schematic, I was actually looking to make an audio amp and this one looks awesome! Although, I was looking for a way to turn this into a 5 Watt mono amp on the datasheet, but couldn’t find anything. :/
    Any help, or am i just being stupid? Should I just use a mono amplifier with similar specs as the tea2025?
    Thanks in advance!

    Reply

  4. Pls oyvind,help me here also(i will download your book sooner by grace)can you provide me with a schematic of 4 stage transistor 2.5w mono or stereo audio amp.pls spare the effort to send me the link to this.God bless.

    Reply

  5. i hav took this ic from my creative speaker and some other parts and made the circuit.but it is not working.i didn’t receive any response from speaker .can u make a video in makin this circuit in breadboard. plz help me

    Reply

  10. sorry
    ‘what is the output power ?’ this Que. was ask by mistake
    I know output power is 5watt

    I mean to ask what is current consumption of this circuit?
    or what is power consumption for this circuit?

    Reply

  15. i have only 10k 6pin potentiometer avaliable….
    so could you tell me how to wire it in above circiut…

    please!

    thanks in advance

    Reply

    • Hey,

      Check the datasheet of your potentiometer to find out the pin configuration, then match that with the diagram above.

      Cheers!
      Oyvind

      Reply

  18. i have a problem with my omega digital karaoke amplifier AV 9715 it make a noise on the speakers i cant hear the sound clearly and its screen dnt display but my main prblm is the sound. Is it the capacitors or can it be the ic 7812 or the sound ic’s on the aliminium plate but they dnt get hot and i also test the voltage on the 7812 input is +- 26v and out is 12v how can u help me i just want 2 knw what to change or replace 4get abt the display i just need the sound first i will appreciate it very much u can email me what 2 do 2 fix it myself on [email protected] please i really need help thanx

    Reply

  19. can i plot this circuit on proteous software? i made this circuit on proteous but it’s not working. pls help me

    Reply

    • Hi,
      I doubt that you find something that will simulate the chip, if that’s what you are trying to do… I would say just go ahead and build it. No need to simulate.

      Cheers!
      Oyvind

      Reply

  20. Hi Mr.Oyvind,
    I manage to make my amp work but the problem i am facing now is the output volume is too low ,can you please help me?
    I use 50v for all polarized capacitors and 100v for non-polarized ,20k potentiometer and powered by 3v rechargeable battery.Thanks in advance .

    Reply

    • Hi Andy,

      If the sound is very low, you can try to increase the volume of your input device. And make sure the potentiometer is at it’s lowest resistance.

      But don’t expect a really loud sound when you’re using only 3V for power.

      Cheers!
      Oyvind

      Reply

  23. Hey, I built this circuit but I’m facing a problem, I’m not getting output in the 2 channels only in one, why could this be?

    Reply

    • Hi, this could be because there are only inputs on one channel. Or it could be that there’s a short-circuit or something on one of the outputs. Try switching the inputs and see if this gives you an output on the other channel.

      Cheers!
      Oyvind

      Reply

  24. HI TO ALL AND GOOD NOON,

    IF ANY ONE CAN HELP OUT.

    ACTUALLY I AM LOOKING FOR READY MADE PRINTED CIRCUIT BOARD FOR KARAOKE SYSTEM (AMPLIFIER SPEAKER, IT HAVE USB TERMINAL AND 2 MICROPHONE + RECORDING FACILITY IN THAT SAME AS LIKE (PURE ACOUSTIC 1215 MODEL)
    NEED 2 SET OF AMP. IF ANY ONE IS HAVING THE SAME PLS SHARE THE DETAIL MY NO IS 9004049095.

    Reply

  27. I have just finished asembling the bridge version and I am impressed of the quality and the power of this IC!

    Reply

  28. Hi, im up to build this little amp for my desktop pc (the built-in speakers are just terrible)
    I haven’t seen the lay out yet (as i don’t own any software for that purpose) but there is a pic at the beginning of the topic that brought a simple question to me:

    Is the layout drsignes to be used with a double sided copper board .?

    Thank you :)

    Reply

    • Hey,

      The design I created was double-sided. But it shouldn’t be too hard to make a single-sided design if you want to do that.

      Best,
      Oyvind

      Reply

    • Hi,
      The incoming signal could be too high. The amplification could be too high. There could be noise in the incoming signal.

      Best,
      Oyvind

      Reply

  32. haai brother my name is sandeep from Kerala I made this amplifier, no any problems ,now I am using this amplifier to my headphones, brother you are great ,don’t damage ur health ,take care bro thanks sandeep

    Reply

  33. hello sir this tharun I just want to create tv signal jammer in that many circiuits are there I just want to solve and create a tv jammer or hotspot jammer I will buy what ever u say

    Reply

  35. Hey, how can I add the input to the speaker? I am a complete beginner to it and don’t know how to do it. Also, can you help me with the Potentiometer?

    Reply

    • For filtering or to avoid oscillations. You might be able to skip some of them, depending on your power source.

      Best,
      Oyvind

      Reply

  38. I have a transformer 230/12V , with this can I give supply power for the chip after converting it to DC? Is the circuit is able to withstand the power supply?

    Reply

  39. Hello Oyvind,

    Thanks for this website. It is very helpful. I want to try making a portable audio amplify for devices like cellphones, mp3 player, etc. with an SD card slot and a USB charging port for a 3.7 voltage battery.
    But I haven’t got a faintest idea where to start with a circuit. Any clue Oyvind would be really appreciated.

    Reply

    • Hi,

      Well, I guess this article is a start. Here you build the amplifier. For the other parts of the project I don’t have any articles unfortunately.

      Reply

    • Yes you can. But if you want more power, check the datasheet for how to connect the outputs in mono-setting.

      Best,
      Oyvind

      Reply

  42. I need to boost a signal sixfold before I divide it by 6 to send to 6 different destinations. Can this be done with an LM386? Also, I do not seem to be able to make the LM386 specs give me hints on how to do it.

    Reply

        • On page 5 you’ll find “Typical Applications” with several circuit diagrams. Connect the circuit diagram as in the one marked with “Amplifier with Gain = 20” and you get 20-fold the signal.

          If you need exactly 6, you can play a round with the resistance on the input.

          For splitting the signal, you can use resistors for basic splitting. Google “signal splitter circuit” to see some examples

          Reply

  43. Hello, I am facing a strange problem with this circuit. The whole circuit wired up this way results in one working speaker while the speaker connected to pin 2 and 3 doesn’t work. I am powering this circuit 12v just so you know. When I was tinkering with the circuit, I found that removing the 470uF capacitor connected to non working speaker and shorting the wire, the speaker starts receiving sound but now the output is way too noisy. I tried replacing the capacitor but nothing happened. Do you have any idea?

    Reply

  45. hlww..i made this circuit and it works great..thank a lot… :)
    i have a question..can i use two outputs in one speaker??
    if i can then how to add??

    Reply

  46. Hy guys my problem is i dont know where to buy those printed circuit boards i live at durban.so idnt know where to find those boards for soldering and how much is it?

    Reply

  47. This is a really cool thing! I am new to electronics so I have a stupid question. How can I connect the two inputs to my laptop if I build this on a breadboard?

    Reply

    • Hey Kirk,
      You need to use an audio mini jack to plug into your laptop. Mini jack on one side, loose wires on the other side to plug into your breadboard.

      Best,
      Oyvind

      Reply

      • Thank you so much for the reply! Another problem I encountered is the TEA2025 chip seems to be a pretty old version and many electronic shops are out of stock. Could you tell me where I can buy it since I wanna start building it in a week? Thanks!

        Reply

  48. I made this circuit and worked perfectly well with only one input and output ,the other output produced noice ,i also made a pre amp ad on it and i made à microphone loud speaker .thanks

    Reply

  49. hi
    This is a great little amp, but im working on a pet project for sound in my car involving, among others, this TEA circuit.

    Here is my idea for ‘poorman’s’ radio:

    I found various completed circuits out of hi-fi systems and portable radios. Im trying to use them all in my car as a complete built in system, without using a radio that can easily be stolen.

    I have wireless bluetooth speakers that came with my phone that i want to put front in-dash, a TEA2025D circuit from an old treadmill and a TEA2025 that i got from an old hi-fi.

    Individually, each one has great power, but i want to make them work together from one source, an auxilliary input and/or, the bluetooth link. Im only using my phone as the music player.

    When i connect the one with the other, a lot of sound disipates or alot of static comes through, giving me the idea that one or the other is getting too much power or drawing too much.

    i can give easch one its own input from the potentiometer, but that o lot of extra wiring in the car as the layout requires the one circuit to be in the back, powering those speakers.

    Is there a way i can link them up together?

    Please give me some advice. Youre welcome to have a good long laugh at my expence first, but my reasons for this idea is not to spend any money on the system and still get powerfull sound, while making sure nobody is tempted to break into my car when they see a radio in the dash. FYI, ive lost 4 radios in 3 months through crime and im done buying new radios.

    Keep in mind, ive collected the proper size speakers for every amp circuit’s rated output.

    Hope you can help

    Thank you

    Reply

  51. Pls my problem is with the schematic,
    Between C5 and C11 you made C6 to pin 15 pass through. Same thing applies to C7, C12 and C8. The question is; are they interconnected on those points. I am soldering but when I reached there I’m confused, so please help me now.
    Thanks for your effort

    Reply

    • Hi,

      Yes they are all connected. If you look closely there is a little dot where they all intersect. This dot means that they should be connected.

      Best,
      Oyvind

      Reply

  52. Thanks for your help. I’m able to make it…but I want you to help me build one that has two TEA2025B. Pls help me with the schematic or circuit. Thanks

    Reply

  53. Please iam okonwo peter obinna a Nigerian I love electronics but don’t know how to follow it up . I enjoy seeing constructed circuits .initially I thought they were been made by ghosts I never knew one can make something wonderful like that . please admin is there a way I can start making circuit’s and see it work PLEASE although iam a higher institution student but academics in my country is very hard because one has to combine so many hustles just to make ends meet

    Reply

  59. It is a good circuit for amplifier, but you have not mentioned the voltage of capacitors (Polarized) from C1 to C8. Please mentioned voltage of capacitors to make the circuit useful for beginners….
    Thanks..

    Reply

  60. I am happy to come across this site, I am somebody who like electronic but don’t have someone to teach me, please I need your help. Thank you.

    Reply

Trackbacks

Leave a Reply

Your email address will not be published. Required fields are marked *