Circuit power audio amplifier with TDA7377 2.1

Circuit power audio amplifier with TDA7377 2.1


Complete circuit power amplifier 2.1, 3 channel with TDa7377, include in the layout, power supply, bass filter as well as the full PCB layout. Project amplifier ideal for various applications. includes in the board, Power Supply, Preamplifier, bass filter, volume and tone control.

About designing amplifier with TDA7377 Stereo 2.1 + bass channel

Circuit to use the possibilities of the TDA7377 which has 4 outputs, 2 simple for satellites and the other two bridged for the subwoofer.
The circuit has balance control (P2), if not just need to connect the jumpers. Adjust overall volume (p1), tone control and volume adjustment of the subwoofer.
We have a pre amp (IC1) and bass filter (IC3) with bandwidth of 20-150Hz.
The circuit already has power supply by simply connecting a transformer (AC) simple 9-12 Volts / 3 Amps or more, can also be connected a source (DC) 12-18 volts / 3 amps. Can be a source of computer or notebook, battery car , etc.

This circuit is not the same as traditional circuit which adopts RC to control Bass/Treble via potentiometers, its Bass circuit adopts Low Pass Filter,doesn’t need additional Treble potentiometer, so it is quite suitable to be used for the power supply refitting for automobile, motorcycle, electric vehicles and multimedia audios, it can help a lot for promoting your sound quality.

Schematic of the audio power amplifier with TDA7377 2.1 – Stereo + Subwoofer


Suggested PCB design for audio amplifier 2.1

PCB copper side
PCB Silk
PCB Silk
PCB component side
PCB component side
Part Value
Resistor 1/4W 5%
R1, R3, 2.7K – Red, Violet, Red, Gold
R2 3.3K – Orange, Orange, Red, Gold
R4, R11, R13 47K – Yellow, Violet, Orange, Gold
R5, R12, R15, R19, R20 8.2K – Gray, Red, Red, Gold
R6, R7 1k – Brown, Black, Red, Gold
R8 68K – Blue, Gray, Orange, Gold
R9, R10, R14, R18, R23, R26 10K – Brown, Black, Orange, Gold
R16, R17 22K – Red, Red, Orange, Gold
R21, R23 1.8K – Brown, Gray, Red, Gold
R22, R24 6.8K – Blue, Gray, Red, Gold
P1, P3 47K or 50K – Dual Potentiometer logarithmic
P2 100k – Dual Potentiometer
P4 47K or 50K – Single Potentiometer logarithmic
Capacitors electrolytic
C1 6800µF
C3, C4,C14, C19, C30 10µF
C5, C7, C8, C9, C10 4.7µF
C6, C28, C31 100µF
C22 0.47µF or Polyester
C33, C34 1000µF
Capacitors Polyester and ceramic
C2, C15, C20, C32 100nF (104) – Ceramic or Polyester
C11, C12 100pF (101) – Ceramic
C13 220nF (224) – Polyester
C16, C26, C27 100nF (104) – Polyester
C17, C18 6.8nF (682) – Polyester
C21, C23 4,7nF (472) – Polyester
C24, C25 33nF (333) – Polyester
C29 1nF (102) – Polyester
B1 Bridge Rectifier FBU8K or equivalent 200V / 2A
IC1 7812 – positive voltage regulator 12 Volts
IC2, IC3 LM4558N or equivalent – Dual Operational Amplifier
IC4 TDA7379 or equivalent – see table in the text
LED1 Red Led 5mm
ST1, ST2 Connector 9-way (Optional)
X1 Connector Terminal Block 2 pin – AC
X2 Connector Terminal Block 2 pin – DC Power
X3 Connector Terminal Block 2 pin – Input right channel
X4 Connector Terminal Block 2 pin – Input Left Channel
X5 Connector Terminal Block 2 pin – Audio output Left channel
X6 Connector Terminal Block 2 pin – Audio output Right channel
X7 Connector Terminal Block 2 pin – Audio Output Subwoofer
Welding, Wire, Box to accommodate circuit, printed circuit board heatsink to the TDA7377, Transformer, Sockets for Op Amp, etc..

Download the PDF files for this assembly – Board, Copper Side, components Side, pads, Silk, Schematic, TDA7377, Datasheet.
Download PDF

Buy kits or Assembled board for this circuit TDA7377 2.1 direct from china to worldwide via Aliexpress.

Free-shipping-DIY-Kits-subwoofer-2-1-TDA7377-power-amplifier-3-Channel-power-ampNE5532-pre-ampError in previous version:

  • The capacitor C27 (100µF) inverted.
  • Remove C26 de 10nF or change to 6.8nF.
  • Change the resistors R8, R10 and R18 47K, from GND reference to + 12V. Pull up terminal of each resistor connected to GND and solder a wire to the jumper after 7812 or pin 8 of the op amp.amplificador-subwoofer-tda7379-potencia-errata-2

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  1. can anybody pls tell me the volts of all capacitors used in this amp because i don’t which capacitor is of which volts to be use in this amp because i am a newbie in this electronic world// pls pls pls

  2. Good day can i ask something deffernt.? It is ok if i install a bluetooth for input for x3 and x4 instead of audio wire.?and How ..?

    Hope can someone answer my queation sorry for begenner question

  3. There is an error on downloading the pdf files. I loved your work and I am new to this field. I am hoping i could use you work for my own personal use. Please email me good sir! Keep up the good work.

  4. He terminado el circuito, 🙂 funcionó muy bien haciendo unas modificaciones. He sustituido las resistencias R6 y R10 por unas de 100K y, ubicándonos el en esquema, conecte el pin 3 del IC1A y pin 5 del IC1B a la salida 12v del regulador 7812 mediante una resistencia también de 100K, y el pin 3 del IC3A también lo he conectado con una resistencia de 100k a la salida 12v del regulador 7812. Suena muy bien en mi equipo.

    Leia mais:

  5. Publicado em 7 de novembro de 2014 às 3:07 pm
    Estou construindo o circuito e eu notei várias coisas:
    Que a lista de componentes para 100uF capasitores a 2, C1 e C26, ea imagem componente obter 3 capasitores acrescentando c12 que está na lista e disse que, para 100nF O Stand?
    Esse pino 9 não está conectado fazer eu deixo bem ou ligar para a terra?
    Eu estou usando um tradutor

  6. Thank you for shairing a nice projec.I’m so intrested about developing this. Since I’m new to fiel please be kind wnough to e-mail me the all details/documents relaeted to above project. Thanks again.

  7. I think this project was only meant to be used with a car battery and the power supply section was just an after thought, you would have to make a separate board for the supply. I will post a schematic later on.

  8. Hello guys,

    circuit is okey and the PCB. After making PCB, fix the IC in their respective place and check its pins are matching with circuit. I had this similar problem. If IC pins are not matching, it will not work. Only solution, during printing the PCB outline, take the mirror image of PCB outline and take print.

  9. hi everyone i build tda7377 sub amp but it is distorting at low and high volume but if i test a power amp with no preamp it sound fine where is da ze problem

  10. Hii… I have installed this circuit. But I am unable to get output volume. Also there is noise in output. Sound is anyway not coming. Please help. Some values and components are missing in part list. Please update and reply for solution.

    • basta ligar 3 resistores de 47k cada entre os pinos 8 e 3 e 8 e 5 do IC 1 (4558) e entre os pinos 8 e 3 do IC 3 (4558). Solde os resistores em cima dos IC’s. Funciona ok.

      • Muito obrigado amigo, estava quebrando a cabeça com esse projeto há 2 semanas, já estava quase desistindo desse amplificador. Agora funcionou perfeitamente!

  11. i build this project but its not working.
    my question is:
    > what is the right resistor? because in your parts list the R21 is 68k but in the component side its 6.8k.

    > Is it ok if i use mylar capacitor?

    hope for your rply

  12. This project is actually a new half level …. I’m getting a
    problem in ic lm4558, if I give the
    current at this power, that happens no
    sound at all who came out in speeker …
    please its support on issues that I’m dealing with this takz….(sory my english is suck)

  13. firstly, thank you for sending me this project. I bought all the materials for this project but I can not get capacitor 100nf(polyester) in my local area. is there any similar capacitor I can use.
    Thank you.

  14. First i am thanking you to give a nice project. It is very useful for a beginner like me.Can you please upload a pdf for pcb copper side ? Which type of speaker and sub woofer i have to use (rating also)?