150 Watt amplifier circuit

admin November 2, 2017 1,069 Comments

Low Cost 150 Watt Amplifier Circuit

Description

This is the cheapest 150 Watt amplifier circuit you can make,I think.Based on two Darlington power transistors TIP 142 and TIP 147 ,this circuit can deliver a blasting 150 W Rms to a 4 Ohm speaker.Enough for you to get rocked?;then try out this.

TIP 147 and 142 are complementary Darlington pair transistors which can handle 5 A current and 100V ,famous for their ruggedness. Here two BC 558 transistors Q5 and Q4 are wired as pre amplifier and TIP 142 ,TIP 147 together with TIP41  (Q1,Q2,Q3) is used for driving the speaker.This circuit is designed so rugged that this can be assembled even on a perf board or even by pin to pin soldering.The circuit can be powered from a +/-45V, 5A  dual power supply.You must try this circuit.Its working great!

The preamplifier section of this circuit is based around Q4 and Q5 which forms a differential amplifier. The use of a differential amplifier in the input stage reduces noise and also provides a means for applying negative feedback. Thus overall performance of the amplifier is improved. Input signal is applied to the base of Q5 through the DC decoupling capacitor C2. Feedback voltage is applied to the base of Q4 from the junction of 0.33 ohm resistors through the 22K resistor. A complementary Class AB push-pull stage is built around the transistors Q1 and Q2 for driving the loud speaker. Diodes D1 and D2 biases the complementary pair and ensures Class AB operation. Transistor Q3 drives the push-pull pair and its base is directly coupled to the collector of Q5.

Circuit Diagram & Parts List .

150 watt amplifier

150 watt amplifier circuit diagram

Notes.

  • Remember TIP 142 and 147 are Darlington pairs  .They are shown as conventional transistors in figure for ease.So don’t get confused.Even though each of them have 2 transistors ,2 resistors and 1 diode inside ,only three pins ,base emitter and collector are coming out.Rest are connected internally.So its quite OK to assume each of them as transistor for ease.
  • Use a well regulated and filtered power supply.
  • Connect a 10K POT in series with the input as volume control if you need.Not shown in circuit diagram.
  • All electrolytic capacitors must be rated at least 50volts.

Power supply for this circuit.

A  +40/-40 unregulated dual supply for powering this amplifier project is shown below.  This power supply is only enough for powering one channel and for stereo applications double the current ratings of  the transformer, diodes and fuses.

amp supply

Power supply for this project

TIP 142 & 147 Internal diagram and pin out.

TIP 142-TIP 147 Pin Out Diagram and Schematics

TIP 142-TIP 147 Pin Out Diagram with Schematics

Note:- We have explained how to create a schematic of this circuit and its PCB using an online EDA tool – EasyEDA.  You may read the article to understand how to draw and develop a PCB of this circuit.

We have more related list of  Amplifier Circuits that you may like to visit;

1. 2 X 60 Watts Stereo Amplifier Circuitis designed using LM4780, an audio amplifier IC that can deliver 60 Watt RMS output power per channel to  8 Ohms speakers.  Advantages of using this IC are low harmonic distortion compared to other IC amplifiers of similar category and a power supply rejection rate of 85db. In addition it require minimum components and a built in mute function.

2. Headphone Amplifier CircuitThis is a simple circuit which uses only 3 transistors, that can be used to drive your headphone. It can be easily built by any one and can be powered using a 3 volts battery.

3. Mosfet Amplifier Circuit This circuit is designed using two Mosfet’s and one transistor; which makes it an easy to build circuit. It can deliver 18 Watts output power to 8 ohms speaker or 30 watts to 4 ohms speaker; you can do it the way you like it. Another advantage of this circuit is the minimal use of components.

4. 40 Watts Amplifier using TDA1514 TDA1514 is a high performance hi – fi amplifier from Philips. It requires a dual +25/-25 volts supply. Advantages of using TDA1514 are low THD, mute standby feature, thermal protection and other features. It can deliver 40 watts of output power to an 8 ohm speaker. You need a proper heat sink for the desired reliability of this circuit.

5. 2 X 32 Watts Stereo Amplifier CircuitThis circuit is built using TDA2050 which is a 32 Watts Class AB Audio amplifier IC (monolithic) . This IC has many features like thermal shut down, low THD, short circuit protection etc. This circuit uses Two of these IC TDA205o; one for each channel.  An 18 volts dual power supply is required to power this circuit.

Comments
  • Jonathan
    May 4, 2013

    Pls sir can dis cct be used as a subwoofer amp? if yes den how…?

    • Seetharaman
      May 4, 2013

      Hi you can use this amp as subwoofer amplifier. feed audio input to the amplifier through the sub woofer filter, appeared earlier as a project in circuitstoday.(sub woofer frequency will be in the range of 80 to 120Hz).

  • Evans
    May 2, 2013

    I have try this circuit and it works effectively.

  • Soumadeep Saha
    April 18, 2013

    We made the whole circuit.. And did the modifications as suggested in the link… http://pcb.jspayne.com/150wattamp.html But even with or without the modifications it is not working… We are getting 40 volts DC at the output of the amplifier… What do you suggest … And how do I check to see if the TIP 142 and TIP 147 is working… Please help!!!

  • youngest C
    April 13, 2013

    Pls sir does the circuit need a heatsink?

    • omer
      April 15, 2013

      yes the two power transistors TIP 142 / 147 need a proper heat sink…

      TIP 41 does’nt need it

      • youngest C
        April 18, 2013

        I used a 450watts-8 ohms speaker bt it rather got blown out. pls wat is the problem?

        • Omer
          April 25, 2013

          hi youngest C ……
          We have built this circuit about more than 1000 times this works well and perfect..
          If you are facing any type of problems regarding this circuit then you can contact us any time….. we are here for your assistance

          We have a complete tutorial ( images as well as videos ) of this circuit’s building procedure…

          If you are realy willing to built this circuit with perfection then contact us below given mail…. we are here to solve your problems… thanks , have a good day

          • October 14, 2013

            dear sir
            can we usded this circut as a stereo with the same power supply +45_45 volt ,or any other changes required .please advise in details .

    • June 2, 2013

      Ofcourse u need to use passive heatsinks b’se thoz are high power transistors

  • youngest C
    April 12, 2013

    Pls sir, its just 1 output of the amp, what abt d other speaker? tanks

    • Omer
      April 25, 2013

      hi ……
      We have built this circuit about more than 1000 times this works well and perfect..
      If you are facing any type of problems regarding this circuit then you can contact us any time….. we are here for your assistance

      We have a complete tutorial ( images as well as videos ) of this circuit’s building procedure…

      If you are realy willing to built this circuit with perfection then contact us below given mail…. we are here to solve your problems… thanks , have a good day

  • youngest C
    April 12, 2013

    Pls, need a pcb layout for 150w amp

  • Seetharaman
    April 9, 2013

    Use the following link and use the pcb design. you can also incorporate the improvements shown to the circuit, which are useful and also incorporated in the PCB.
    http://pcb.jspayne.com/150wattamp.html

  • Peter
    April 8, 2013

    sir pls share PCB lay out and the analysis of this circuit 150 watts.

  • Soumadeep Saha
    April 7, 2013

    The 33 ohm resistance in the circuit where -45 volts is applied is burning out and glowing red hot… What seems to be the problem…

    • Seetharaman
      April 8, 2013

      Hi Saha It looks like your TIP142 is dead short. Kindly do a cold check of TIP142 between collector and emitter. Anyway check all the connection ensure you start with a DC voltage of plus minus 30volt DC and an 8ohms speaker. If every thing is in order use 45 volt DC supply with 8 ohms speaker. Since this circuit doesn’t have output short circuit protection circuit built in, (as we have maintain least component count)hence use 3amp fast blow fuse initially in positive and negative dc supply line to protect the output transistors. Once the system is healthy replace the fuses with 5amps.

      • Soumadeep Saha
        April 12, 2013

        Thank but there seems to be another problem… I was using another pre amplifier with this circuit and I accidentally opened the connection for negative feedback thus increasing gain and bursting the 100 uF cap…Since then I am getting a voltage from ground…(i.e ground is at a higher potential)

      • Soumadeep Saha
        April 13, 2013

        And can you tell me a test to know if BC558 is fine and also can you suggest an alternative…

    • omer
      April 15, 2013

      recheck the circuit if its on PCB …..

  • sagar
    April 2, 2013

    Hello every one i have made this circuit it is eorking but the output of this amp is very low even when i onnected a 12″ 150 watt speaker with 30-0-30 l5 amp transformer so could any one tell me how should i get full 150 watt output frm my speaker plzzz

    • sagar
      April 2, 2013

      sorry in the above comment i have typed 15 amp transformer but it is only a 5 amp transformer sorry for my bad typing

    • Seetharaman
      April 8, 2013

      Hi Sagar what is the impedance of the speaker. it should be 4 ohms with 30volt supply to get 150 watts. input signal to the amplifier should be at least 600mV rms (line level) if it is less add a simple 10 gain pre-amplifier between source and the amplifier.

    • Omer
      April 25, 2013

      hi ……
      We have built this circuit about more than 1000 times this works well and perfect..
      If you are facing any type of problems regarding this circuit then you can contact us any time….. we are here for your assistance

      We have a complete tutorial ( images as well as videos ) of this circuit’s building procedure…

      If you are realy willing to built this circuit with perfection then contact us below given mail…. we are here to solve your problems… thanks , have a good day

  • kobena
    April 1, 2013

    i tried this 150w amp the first time with tip 142,147 and 41c it worked well but it is over heating.however i discovered that tip 41 and 41c are different in value so i am working on that now.

  • March 20, 2013

    thinks its vry nice and helpfull circukts

  • Ricochet
    March 13, 2013

    Is this circuit gonna work even the other components here http://pcb.jspayne.com/150wattamp.html are not placed? Thanks in advance!

  • March 12, 2013

    i also want to know if it can work even if the supply is less than 40. tnx

  • March 12, 2013

    sir , i just want to ask if this circuit can amplify inputs coming form mp3. and if this is mono-channeled
    tnx

  • March 11, 2013

    HI NEED TV CIRCUIT

  • CHANDRASHEKAR
    March 11, 2013

    Sir, Assembled the circuit for 150w power amp,it did not work.we are getting only humming noise. Initially DC supply connected was 17V dc dual supply for try out.is it necessary that max volt to be connected.what may be the reason,out put base voltage is max(13v) on both 142 &147 power transistors.would you kindly let me know the reason also please forward ref.voltages.
    Regards kindly reply\Chandrashekar

  • Ismael Issah
    March 9, 2013

    Thanks to u guys for the education. l want to try my hands on this Amp (150 W) and want to ask, does TIP141 transistor the same as the TIP142 transistor in this circuit? And therfore can l replace TIP142 with TIP141?

  • March 8, 2013

    plias tell me nomber transistor sacet 207

  • March 8, 2013

    pls mr i need to sarcet diagram sherwood amplifer model no ra-11114t prias help

  • omer
    March 3, 2013

    hi can any one tell me that if i use this amplifier with 4ohm load then ???

    • rohin
      March 4, 2013

      hi, this amp cannot support the 4 ohm load because it has only two transistor at output.it will overheat on 4 ohm load and will burn.at low bass it will be ok.

  • Christian
    March 2, 2013

    First of all, sorry if this is a stupid question. But I’m total newbie on audio amplifiers! With that said, now to the question:

    I have a couple IRFR2497, can I use this layout and replace Q1 to Q5 with those? I understand that I might need to have different values on resistors and such.

    Kind Regards
    Christian

  • Soumadeep Saha
    February 18, 2013

    i would like to know the wattage of the other resistors

  • Jyo
    February 13, 2013

    please share the information related to digital storage oscilloscope….

  • omer
    February 1, 2013

    https://www.facebook.com/auxtics

    see this amplifier working in stereo mode.

    sound is amazing and mirror cracking…

    Questions related to this design will be answered here. thnx

  • Vijay
    January 23, 2013

    Hi Seetharaman,

    I’m planning to build this circuit. Since I’m going to make a stereo, I need to double the power rating of the transformer. I’m planning to order a 30-0-30 10 or 12A transformer. Could you please let me know if that will be enough? If that’s the case, more importantly, I would also like to know which diode I should use for the bridge rectifier. Can I use two P600A in parallel? what would be the voltage drop?

  • January 23, 2013

    hi all, i have built this amp 7 times, each time i am left with an amp that has fail each time with +v rising to full psu volts the neg supply dies to 0v. the speaker 0 volts has half volts at this point. the – supply falls to zero. the npn o/p device has on, 3 times blown its guts out. i found a circuit by vellman 100w 200wmp kit and noticed that the 150w amp is a stripped down version of the 150w one. i am a electronic design engineer in the u.k. and notice that using a scope i have found that this design is as stable as a brick in custard, sorry guys, but with all the mistakes in and on the circuit it shoud have been fully noted with corrections and fully tested BEFORE it was issued to the net. i have never found a circuit to SO DODGIE. and released to the public.
    Unless someone can save this amp from distruction each time i conect it to a power supply i would all avvid builders to not to bother with this design. i have used a power supply (dual) +/- 2v to 100v this amp has failed at +/- 15v @6a and it still blow up ? my fear is regardless of layout(s) and i have tried 4 different methods and layouts including one from the original pictures AND IT STILL BLOWS UP?
    THANKS TO ALL FOR READING THIS AND IF THERE IS A CURE FOR IT PLEASE LET ME KNOW

  • Hallotje
    January 11, 2013

    can i use a 30-0-30 v 8amps trafo for a stereo amplifier?

    • Seetharaman
      February 11, 2013

      you can use but ensure that for each channel positive and negative bus add a 3A fast acting fuse to protect the output transistors against load short circuit as there is no protection circuit included in this simple design.

      • March 8, 2013

        plias tell me oll transistor use for this amplifier

  • sina
    January 8, 2013

    Hi, I’m here to find transistor tip 147!
    The type of transistor, the transistor, which is the same.
    I am Iran
    Two’m Goodbye
    This is just a quick answer.
    **
    Similar tip147 transistor is?

  • prudencio g.peritos jr.
    January 6, 2013

    I had been adding BD 139 and 140 to my second amplifier with TIP 2955 and TIP 3055 AND ITS WORKING GREAT when i convert to stereo its working great,thank you for this site,I learned and gained more knowledge about amplifier…

  • dioniz edward
    January 2, 2013

    can i have the data analysis of the circuit because my friend asked me why did i use BC 558 and not other kind of transistor i didn’t find an answer can you help please?

    • rohin
      January 5, 2013

      you can use other transistor but this is good and cheap.if your friend is intelligent then you can ask to him for other transistor.

  • neimat
    December 28, 2012

    Dear sir,I did ​​this ampli but I have a problem, that in the entrance of audio I have a wave signal (12V, f = 1Hz), but I obteint in the output of the amplifier square signal ? why? it’s logic? please advice

  • prudencio g. peritos jr.
    December 28, 2012

    Atlast i had been enjoy my amplifier using BDW 83c and 84c with Passive Baxandall Tone control its working great. Now i assembled another amplifier using TIP 3055 and TIP 2955 its working great also,,,and i plan to add another transistor using BD 140 and BD 139.,,hoping it will work soon

    • sagar
      April 2, 2013

      well hello Mr.prudencio g. peritos jr could you post your amp ckt video plzz , i have done this amp ckt but it’s output sound is very low could you plzz guide me( i have used 30-0-30 ,5 amp transformer also but it’s output is less)

  • soumen
    December 21, 2012

    i want high bass audio circuit board.

  • rohin
    December 15, 2012
  • ermsk8er
    December 14, 2012

    Hello again! My TIP41 is overheating and suddenly my R10 (33 ohm) fried/busted. Please help me. 🙁 tnx!

    • rohin
      December 15, 2012

      change your tip 41 and r 10.check your all connection.for help contact me by email .rohin.sharma83@yahoo.com

      • ermsk8er
        December 18, 2012

        Thank you very much, sir! The base and collector of my tip41 was shorted 😀 Sorry for late reply. Now its working! Thanks again!

  • rohin
    December 14, 2012
  • rohin
    December 14, 2012

    hi to everyone,For pcb of this nice amplifier is available. http://pcb.jspayne.com/150wattamp.html.Don't use update version.

  • ermsk8er
    December 13, 2012

    Can i use 1 heatsink to transistors; tip41, tip142 and tip147?

  • December 11, 2012

    sir robin just a little bit correction to my email add and this regards with the PCB of the 150 watt power amplifier circuit i am asking to please send me a layout, thank u & more power
    jsl_7458@yahoo.com

  • December 11, 2012

    12 December 2010 at 1240H
    a very nice circuit and thank u so much for sharing! by the way sir robin can u pls share me a PCB layout of the 150 Watt amplifier circuit. Thank and please, more power and GOD Bless…

  • jay
    December 11, 2012

    sir pls share PCB lay out and the analysis of this circuit 150 watts,., nusoncar@yahoo.com

  • ermsk8er
    December 11, 2012

    Nice one circuit, thanks for sharing it! By the way cAn anyone send me the pcB layout for this circuit.. Thanks again.! God bless!
    My email – erm.sk8er@yahoo.com

  • December 9, 2012

    Im having a hard time looking for a 120V to 30V step down transformer for this circuit. Can somone please tell me where I can find these components? Post or send a link if possible please

  • nitin khandelwal
    December 2, 2012

    what is the basics theory to design such type of circuit?how shall we start to think to built such circuit if we beginer of electronics?…which comp. is required or not?..how can we justify which comp. is connected at perticular place.if i use 4 darlington then what happen if any link there to know about these plz tell me.

  • AKANINYENE IKOEDEM ESSIEN
    November 29, 2012

    pls sir i need a circuit diagram of audio receive,

  • harssh
    November 27, 2012

    hello Mr. Seetharaman
    well i have gone through your circuit and its quiet intresting so i have done it on a pcb but it aint working so could you help me how to check it or what to do plz….

  • November 19, 2012

    Hello Seetharaman sir!
    it very interesting working on this circuit.
    Sir i have used 32v-0-32v 8amps transformer for this circuit you have mentioned to use 30v-0-30 3amps transformer but i am using 8amps wil it create any problem?
    and in this circuit the output terminals from pcb is having 46v when checked with voltmeter when checked with no input,

    • rohin
      November 20, 2012

      your transformer is ideal for this circuit.after rectification you will get 45v which is good for this amplifier.

  • Prudencio G. Peritos Jr.
    November 12, 2012

    thanx bro i sent you an email with the link which i got the PCB layout,,,hoping your reply soon with you suggestion or advise

  • Prudencio G. Peritos Jr.
    November 11, 2012

    You are right Rohin,,when i checked the output with the tester ,i put it at 250 volts,,and i found out that there’s a voltage came out…that,s why the music is not clear…I add some 2 resistors and now the diction is clear alredy..i used 16 sqr inch heatsink because the Q1 is so hot,but the Q2 and Q3 is normal,..can you suggest me regarding this problem, please,.
    I used TURKISH PCB Layout,,,using BDW83C and 84C,,with TIP 41 and BC556…with POWER supply of 24-0-24v,6A…Please suggest me regarding the Q1 is so hot…Longing you reply soon.

    • rohin
      November 11, 2012

      hi bro, as you said that there is some volt on output so there is some fault in you design. you used good alternative transistor so problem is not due to alternatives transistor.if your q1 is going hot n hot it will blow after some hour.first wash it with thinner then check polarity of all capacitor and good look at ground pin.you please give me link of pcb layout and component list that you used in your circuit because my guess is that you didn’t wrong anything problem due to any wrong component and wrong value resistance.my email id is rohin.sharma83@yahoo.com.

  • Prudencio G. Peritos Jr.
    November 7, 2012

    Thanks rohin ill check it…and you will know further

  • S.alam
    November 6, 2012

    can any one please send me pcb layout of this circuit
    at
    alamisdecent@gmail.com

  • Prudencio G. Peritos Jr.
    November 4, 2012

    Sir, i have done already assembled this amplifier, using BDW83c and 84c, it is very loud but the diction or wording of the music is not clear..and Q1 is very hot even I am using 3″ x 3″ heatsink…please help me, what shall I do regarding my amplifier..
    Hoping your reply soon. Thanx.

    • rohin
      November 5, 2012

      dear bro ,i already made this amp. amplifier is beautiful and clear sound and loud too.it seems that there is something wrong in your amp. R2 should be 220 ohm.if everything is fine then problem is due to alternative transistor.and made this amp as it is.don,t use its updated version where some one put more components like pf and resistance. check the output of amp with multimeter put the scale to dc 200v plus and it should be zero.if there is some volt then you did something wrong.

  • S.alam
    October 15, 2012

    hello sir i have build this amplifeier with 24v &1amp transformer and there is too much distortion i use speakers of 35 watt 6ohm
    please answer what should i do?

  • miloh
    October 13, 2012

    sir why does the sound not amplified?? i change all the transistors that i use. what should i do???

    • rohin
      October 17, 2012

      if you made it on pcb then pcb may be short one track to another or your flux is not removed on pcb .wash it with thinner or if you made this amp with additional component like pf and resistance then remove them.their is minor fault in your circuit or you fit wrong way any component.

  • ALams
    October 11, 2012

    hi sir
    can you please tell me how to convert this amplifier into stereo?

  • Prudencio G. Peritos Jr.
    September 30, 2012

    hello sir,
    what transistor can i replace TIP 142 and TIP 147?can i replace also

    TIP 41? for matching Q1, Q2 and Q3

  • normzhie
    September 25, 2012

    i used 45v vdc and i have a pre amplifier connected in a 150 watts amplifier. then i try, the circuit is good and theirs no problem on it . but i confused i try to volume at 50% with a load at input at no power then i turn on the fused blow out together wid tip 142,147 whats the problem on it sir?

  • August 25, 2012

    HI sir i have a 142 & 147 with amplifier,when i playing this its too hot.can i chenge 142 & 147 to tv’s power horizental transisters like sd1410,sd1550.Please reply.

    • Dissanayake
      September 23, 2012

      TVH-out is not a darlington transistor and it is low current and high voltage drive transistor. You have to try with larger heat sync and cooling fan can apply. in other hand you have to replace 142 & 147 only with darlington types.

    • Seetharaman
      September 25, 2012

      Hi Chhotu The power is RMS voltage available across speaker terminal, V square / speaker impedance. It is clear that for higher power you have to raise the voltage or reduce the speaker impedance. your heating up may be due to higher no signal current for the output transistors, chech the D1 and D2 loop.

  • ashish
    August 22, 2012

    sir please tell me how you decide the output power as here you have said its cheapest 150 watt amplifier circuit.

    • Dissanayake
      September 23, 2012

      Basically output power is depending on the supply voltage and impedance of the speaker. P(out) = sqr(V-10)/R.
      V: supply voltage (45v)
      R: impedance of the speaker (8Ohms)
      here 10 is the voltage drop by the darlington.

      you can increase the output power by reducing the R or 10.V
      to reduce the 10V drop you can apply more output darlington in parallely with 0.33/7W resistors.

  • Boogie
    August 13, 2012

    Good day sir, I built 3 of this wonderful amp without any problem, except for the “excessive heat” of the Darlington pair. I used a fin type 3″x5″ heatsink for each transistor. I know I can use a bigger heatsink but my question is, what causes the Darlington pair to “overheat”.
    Pls. reply to my e-mail…..

    Thanks and more power…

  • prithvi
    August 10, 2012

    sir i have a 44v-0-44v 5a tranformer . After using capacitor 60v-0-60v is available ,i can use this circuit for this psu?

    • September 23, 2012

      hey prithvi, go ahead do not worry about supply. you can use this t/r. but take care that you have to use filer condencer of 75 workig volt.do not forget it.it is better to use instead of 63 woring volt cond.and one more thing ,use 33 ohm one watt resistences as a current limiting resistences to connect positive and negative supply of an amplifier.if you do not use these resistences then both the tr, tip 142 and tip 147 blown off in less than a second. because i have tested this amplifier today.it works well.

      • Dissanayake
        September 23, 2012

        Manohara, applying 33 ohms resistors is not recommended. because the power amplifier is consuming variable current while it is working. so voltage drop across the 33 ohms is variable. Think the amplifier consuming about 1Amp current. so voltage drop across the 33 ohms is (V=IR) 33Volts. the power supply is about 40V the voltage of the amplifier is about 10V. So this is not the right way. Prithvi, I recomended you to increased voltage of all the capacitors up to 70 volts or more. and Vce of all the darlington transistors should be at-least 80V. Vce of all the other transistors should be at-least 120V.

      • prithvi
        September 30, 2012

        thank you for reply .i was waiting for the reply for 3 days after that i tried it from 32vac to 56vac(45vdc-79vdc) from a 550va 8 kg transformer and i used 4 transistor per channel, my two 120mm 8” speaker’s blown . But transistors are fine ,this amp pays back every thing with less hifi quality.

    • Seetharaman
      September 25, 2012

      Hi prithvi all the transistors may blow up. Never use higher than 30 – 0 – 30 Volt RMS @ 3 amps transformer.

      • prithvi
        September 30, 2012

        sir i have asked tis que. bcos i have spent time and inr 2k for making 44-0-44 5a with auxilarary winding 12v 2a transformer . I have used parallel 142 and 147 with no problem or blowing of transistor and i used bc 556 for pre amp.

  • rey?
    July 30, 2012

    sir? if rectifier diode in the power supply is 6A05. its okay sir? tnx sir and God bless always^^

    • seetharaman
      August 15, 2012

      Hi Rey use 6A10 6amps 100piv rectifier

  • July 18, 2012

    Hi samshith,in reply to your request.I am happy to announce to you that i can give you all necessary information you need on this amplifier circuit and other audio system information.I am the MD/CEO of my own electronic fabrication centre,I have trained alot of people and also written some book on sound system and electrical gadget.Should you are interested contact me via my email.

    • August 6, 2012

      statement: design an audio systm f a fitnes clb f an area 700 sq.feet with glass windows and conseald sealing with following specifications
      instruction mikes,cd/dvd player,appropriate signal conditioning ckt,suitable pre and power amplifier ,7 band grafic equalizer,volume control,tone control,sound level indicator,distortion cancelling ckt,power supply with sht ckt protection and power on indicator,speaker should be column and sealing ,mixed arrangement.

      drawings:
      amplifier enclosure ,half schematic ,sample drawing of sealing and column speaker,connection diagram….

      please let us no it………..by tomorrow….it’s very urgent sir………..help us….it very urgent……….

  • prudencio g. peritos jr,
    July 16, 2012

    sir, as per power supply diagram c1 and c2 is 4700uf,,,c3 and c4 is 100nf,,,100nf is no available in our market,,,what capacitor shall we replace this 100nf capacitor? please confirm…thanx

    • Dissanayake
      September 23, 2012

      the minimum of C1 and C2 should be 4700uf electrolytic and c3 and c4 should be around 100nf and should be in Mylar type. (68oouf, 10000uf also better for steady current).

      c3 & c4 are acting as high-pass filter and reducing high frequency oscillations in the power supply. any value between 0.1uf (100nf) and 0.22uf (220nf) are ok for c3 & c4 (both c3 & c4 should be same)

  • prudencio g. peritos jr,
    July 16, 2012

    hi sir, 30-0-30 volts is not available in our market, can i used 24-0-24 volts transformer 6A ?,,thanx

    • Dissanayake
      September 23, 2012

      The supply voltage is important factor of output power of an amplifier. There is no doubt to apply this transformer to this amplifier. only thing is the output power will be low than the given value.

    • September 25, 2012

      YOU CAN,BUT IT WILL GIVE LESS AMOUNT OF 150 WATTS

  • Prudencio G. Peritos Jr.
    July 12, 2012

    Sir, thank you so much for answering my comments… Have a nice day,,,God bless you

  • Ljay
    July 12, 2012

    Hello sir Seetharaman, I’m from Philippines, Manila I would like to ask if what speaker should I provide building this amplifier using all same active and passive components except that I’m only using 4Amp 30 – 0 – 30 transformer.

    I’ve just build this right this morning and it seems working fine without smoke appears only that I don’t have a speakers yet. I’m a Student!

    Thank You Sir!

    • Seetharaman
      August 8, 2012

      Hi Ljay. You can use 100watts 8 Ohms 12″ full range speaker, in an air tight 65 litres inner capacity enclosure.
      Hi Ray use 6A10 to be on the safer side.

    • Dissanayake
      September 23, 2012

      I tried this circuit with several darlingtons and three way speaker system. also I applied integrated speaker protection circuit to the output of the amplifier. it is recommended to transistor amplifiers because to protect the valuable speakers. the amplifier has very good low frequency (bass) response and it is recommended to apply good low pass filter at the input of the amplifier was trying to oscillating at high frequencies. I thing it is good to apply two way or three way speaker system with good bass woofer rather than a full range speaker. you can also apply a good cross-over circuit for hi-quality music response.

      • Mano
        March 18, 2015

        Hi,

        Can you pl give the integrated speaker protection circuit diagram that you have added in this circuit so that i can make this circuit as a more efficient one.

        Appreciate your assistance.

  • Seetharaman
    July 10, 2012

    Hi Prudencio By keeping the flat surface dowm and ensuring that the pins are pointing to you. Left side pin is emitter center top is base and right is collector.

  • July 10, 2012

    i’m olso interested on constructions of amplifier circuit, but i dont have enough basic obout transistors. i’m doing electronic 2 in computer system engineering. so can you please help me to find more information by sending me some simple circuits to construct.

  • Togor
    July 9, 2012

    The designed is ok d output power is recommented.the heating effect is mush as power suply increases what could be done to use circuit at +70 & -70volt look forward to hear from you.mail me dialinton power transistor that can withstand 80volt

    • July 18, 2012

      Hi Togor,concerning your request contact me via my email.I promise to give you better power darlington transistor that can withstand 100 volt and 45 amp.Am MD/CEO of BODNIK TECHNOLOGIE VENTURE here in Nigeria.And i specialised on sound system fabrication.

  • prudencio g. peritos jr,
    July 8, 2012

    sir, can you give the pin out of this transistor BC 558,the store did not give the pin out,,,im beginner,,,thanx

    • September 25, 2012

      PRUDENCIO,YOU PIC THE TRANSISTER BC 558 ,UP SIDE THE CASE AND FLAT SIDE OF T/R IN FRONT OF YOU & LOWER THE SIDE THE PIN OF T/R, THEN THE RIGHT PIN IS EMMITER,THE CENTRE IS BASE AND THE LEFT ONE IS COLLECTOR.

  • Pankaj
    July 6, 2012

    thanks sir……

  • Seetharaman
    July 5, 2012

    Hi Pankaj 12″ 150 watts woofer is best suited in an air tight enclosure, with an internal volume of 45 to 60litres.

  • mustafa kuşcu
    July 4, 2012

    süpperrrrrrrrrrr power supply

  • Pankaj
    July 3, 2012

    sir can I use a 12inch 150 watt sub-woofer driver with this circuit?????

  • Pankaj
    July 3, 2012

    Thanks a lot sir for your support and help.

  • Seetharaman
    July 3, 2012

    Hi Samshith 63 volts or higher.
    Hi Pankaj why not? you can use with the sub woofer filter appeared earlier in circuits today
    http://www.circuitstoday.com/low-pass-filter-for-subwoofer

  • Bert
    July 3, 2012

    Hi sir if i build this amplifier in two channel it will work or not? Plz reply..,

    bert from mindanao, philippines..


    Via MebApp.com

  • samshith triprayar
    July 2, 2012

    sir, i would like to made it. So help me. I want to know capasitor4700uf volt?

  • Deogratia
    July 2, 2012

    Dear Sir.
    i am happy to get in contact with you, please i need your help concerning this amplifier, When i assemble the amplifier in Mono, it works well, but when i make it stereo, the left channel or right channel will not work, i inter changed all parts from left to right, one chanel still maintain this fault, Please what can be the solution to this? do i need to assemble a split power supply using the same transformer or two transformers for this amplifier, then my second question is that, can i bridge this amplifier to Mono to get more power out-put that can drive my 4 pieces of 21Inches speakers for commercial use? please my email address is(dnkwenti@gmail.com) any help from members here would be appreciated, i am happy to share with good hearth people.
    Thanks

  • Pankaj
    June 30, 2012

    sir please help me I want to use this circuit for subwoofer how can I use it??????
    Can I use a low pass filter??????
    if yes then please provide me the circuit diagram….

  • Seetharaman
    June 28, 2012

    Hi Spharow with 24-0-24 transformer with 8 ohms speaker the output power will be around 60 watts. You require an input of not less than a signal level of 250 mV. Use a pre amplifier with a gain of 10 to 25.

  • Spharow
    June 27, 2012

    But having this 24V 0V 24V is not loud enough for me to play my e.guitar?what’s the power of the speaker do I need to use?Or do I need to put preamp before it,plz repz…

  • Spharow
    June 27, 2012

    Thank you so much, I already found out the fault. The positive line of the of the speaker is shorted unto the ground..tanx..:)

  • Joerz
    June 27, 2012

    Hi sir, good day.
    If I build this amplifier in stereo it will work or not?
    please reply.
    thank you.


    Via MebApp.com

  • Benson githaiga
    June 3, 2012

    Hi Sir its my desire to work on this circuit very soon,please send me this page in my email to facilitate my study and reference as i work on the project.thanks God bless

  • joe
    May 29, 2012

    I have done this schamatic but went i combint the p.supply on power Ac…the
    Power ampl. Have sound sudenly for a second sound stop…just hear the voice tottt………

  • isaac hlengani
    May 20, 2012

    Thanks for the good work,
    Thats very powerful amplifier.
    I’l try to construct it coz it is visible and understandable,
    God bless you keep it up to assist us as student.

  • May 9, 2012

    hi! sir, can i ask? what is the wattage value of all the resistor and the voltage rating of all the capacitor’s?

  • Seetharaman
    May 4, 2012

    Hi Ramdas I have sent the email it had returned. send your letter to my email id seethasub@hotmail.com

  • ramdas
    May 4, 2012

    Dear Br. Seetharaman…I have 2 requests
    1)I want to assemble this 150W amplifier (TIP142/147)..But from where I can get the PCB layout or readymade PCB kit…
    2)Can u please sent me ur email address..cause I have one old Tone control PCB by Visha electronics..of the circuit published in Elektor India.long back..i think in 80s.I dont have the circuit diagram..if i have ur email address I can attach the photograph of the same for ur kind perusal…I tried a lot for this..pls help me out..
    With hope..
    Ramdas.(n.ramdas@yahoomail.com)

  • seetharaman
    May 2, 2012

    Hi Anbu please go through the following link
    http://pcb.jspayne.com/150wattamp.html

  • Anbu
    May 1, 2012

    how to assemling this cuit

  • Tosin
    April 24, 2012

    Thats very kind of you sir, you’ve been a blessing to us.

  • Seetharaman
    April 24, 2012

    Hi Tosin they are power Darlington transistors with freewheeling diodes and currnt limitting resistors. You can fabricate then by using TIP2955/ TIP3055 matched pair (Any High Voltage high power)output transistors with BD140/BD139 (any high voltage medium power)with IN5404 or IN5819 as freewheeling diodes .

  • Tosin
    April 23, 2012

    I want to know if there are other transistors which can replace tip142, tip147 in the diagram because these ones are not available in my area now. Thanks for the good work

  • Seetharaman
    April 19, 2012

    Hi John you can use 10KuF 63 volts in each supply line. (both positive and negative voltage). You can always use a higher power amplifier with a little lower power handling capacity speakers, nothing will happen. The other way, the distortion generated by the lower power amplifier can damage the voice coil of the higher power speakers.

  • prudencio g. peritos jr,
    April 19, 2012

    thanx a lot sir,,,MAY GOD BLESS U

  • john
    April 17, 2012

    is it ok if i used a 80 watts amplifier to 150-200watts speaker ??? thanks

  • john
    April 12, 2012

    can we use a 10k uf 63 volts capacitor in the power supply?

  • Seetharaman
    March 30, 2012

    Hi Rusty TIP41 is NPN, which is required here. TIP42 is PNP with which you will blow the output transistors.

    • August 19, 2012

      HELLO SIR this circuit work or not… plz

      • September 25, 2012

        THANASEKAR,I HAVE TESTED IT EARLIER,IT WORKS GOOD.

  • RUSTY HEARDER
    March 29, 2012

    MADE PC BOARD AND ASSEMBLED IS Q3 A TIP41 OR A TIP42. WHEN SWITCHED ON
    3WITH 25V SUPPLY Q4 AND Q5 BLEW ANY IDEAS PLEASE.REGARDS RUSTY.

  • Seetharaman
    March 29, 2012

    Hi John no need to use screws just slide on the clip.

  • john
    March 28, 2012

    what is clip on ?
    thanks a lot bro ..

  • Seetharaman
    March 28, 2012

    Hi John it is a must, for TIP142 & 147 you require a large extruded alloy heat sink. for TIP41 a clip on will do.

  • RUSTY HEARDER
    March 28, 2012

    Good day , I have Query, Ive biult the 150watt amplifier but have a problem. In the write up it calls for a TIP42, but in the diagram it calls for a Tip31. when I connected up with Tip42 r4 burnt up including Q4 & Q5. on replacing them it burnt Q2 ,Q3 Q4,Q5 R10, c2.
    I had a30volt supply. could you throw some light on this.
    Regards Rusty. rhearder@intehom.co.za

    • admin
      March 30, 2012

      its TIP 41

  • john
    March 27, 2012

    heatsink for the three TIP are needed??? please answer thanks

  • Seetharaman
    March 27, 2012

    Hi Prudencia please refer my earlier comments on this
    December 15, 2011 at 9:46 am

  • prudencio g. peritos jr,
    March 26, 2012

    hello sir. as per diagram Q1 is TIP 41? or TIP 141,,likewise the capacitors ,the volt was not given for every capacitor listed in diagram,,,

  • john
    March 26, 2012

    heatsink is needed for tip142 tip147 and tip41 ??what kind of heatsink is it??
    Thanks seetharaman..
    Pinoy ako

  • Seetharaman
    March 25, 2012

    Hi Many connect a 22k or higher value potentiometer for volume control. Connect one end to 0 volt line and the other end to input and potentiometer’s center pont(slider) to audio in of the amplifier.

  • March 25, 2012

    tnx seetharaman, i using for my mobile sound system big horn tweeter if you have more compatible amps for tweeter can i request more fabor.

    Tnx and more blessing to you and CT….

    Respectfully yours,
    GILBERT
    PHILIPPINENS

  • March 25, 2012

    how are you to connect the variabel resistors to vary the volume

  • Seetharaman
    March 23, 2012

    Hi Gilbert reduce C2 from 10uF to 1nF. Add a 47PF from Q3 collector to base. Why do you require so much for tweeter power?

  • March 22, 2012

    Sir Seetharaman
    A nice day, if I use for tweeter power amlifier this circuit what is the modification.
    Tnx alot Gilbert…

  • Seetharaman
    March 22, 2012

    Hi John with low value potentiometer while it is set at extreme ends will get burnt, hence a fixed resistance is preferred.

  • john
    March 22, 2012

    thanks seetharaman

    no potentiometer ?

  • Seetharaman
    March 21, 2012

    Hi John you can use 3nos 1 ohm 2 watts (which is standard and freely available)resistance in parallel to get 0.33 ohms 6 watts.

  • john
    March 21, 2012

    what if r8 and r9 is not available in the market ? what should be replacE ?thank !

    from the philippines PINOY !

  • Seetharaman
    March 19, 2012

    Hi all capacitors should be 50volts or higher

  • john
    March 19, 2012

    in this schamatic 150w ampl. the all capacitor did’t swo how much volt u can put?c1,c2,c3……including the power supply c1,c2,c3,c4…..all this capacitor did’t swo how much can put?pleeeseee…….imfom. me…this ergent!!t.Q…

    can i use 6A in transformer > the value of others will affect ? help me tnx

  • brian
    March 18, 2012

    what is the voltage of 100nf ?? thanks …

    • June 2, 2013

      The pins for the audio output of any audio system. E.g Radios, mp3 etc

  • brian
    March 18, 2012

    what should be in AUDIO IN ?? beginner thanks

  • brian
    March 18, 2012

    how many watts in R1 , r2 , r4, r6 , r7 and r10 ..thanks

    • September 25, 2012

      BRIAN,R1,R2,R4,R6,R7 CAN BE USED 1/4 OF WATT BUT R10 SHOULD BE OF 1WATT.

  • panos
    March 17, 2012

    seetharaman sory for asking you a lot of cuestions but i measured 75watts into 8 ohm load.if i use two pairs of tip14x conected in paralel i will take 150watts rms ito 8 ohms?thanks for your help!

  • March 8, 2012

    thanks circuittoday, I’ll try to my project..

  • krishna
    March 7, 2012

    Hello sir I am having some douts…….
    1. I am having a (24 w 4ohm)*2 speaker,is dis circuit suitable for powering it
    2. Normally in stereo circuit we hav 2 inputs (R&L)but in dis circuit i can find only one.. So do i hav to make 2 circuits for stereo output I.E (150w circuit * 2)?..

  • panos
    March 3, 2012

    thank you seetharaman!

  • Seetharaman
    March 1, 2012

    Hi Panos you can use any tone control which uses plus and minus supply similar to our Passive tone control, which is most suited for this project.
    http://www.circuitstoday.com/passive-tone-control-circuit

  • panos
    February 29, 2012

    hi sir i made this circuit.its working grest!!can you sugest me a tone control circuit for this amp?

  • seetharaman
    February 24, 2012

    Hi Rush you can use two capacitors in parallel. it will suit. you can use ceramic or polyester capacitor rated for 50volts or higher

  • February 23, 2012

    Hi sir,

    Plz suggest me about query posted on February 13, 2012 at 8:12 pm

    thanx a lot

  • Seetharaman
    February 23, 2012

    Hi Spharow check the bias diodes D1 & D2 direction, the end with a white band is cathode.
    Have you insulated Q1 & Q2 from heat sink with proper mounting kit.

  • February 22, 2012

    I’ve assembled it but the moment i run it, the wire from power supply(+) is melted and burn the wire..(0) is on the ground and (-) is on the collector of tip147..I’m just using 24v 0v 24v..what’s the problem?I’d rechecked it over and over again but the circuit is just rightly connected..

  • T0C
    February 20, 2012

    Hi Tmaxx226,
    The 300VA transformer should do just fine for the stereo application, but I recommend using the 500VA instead, having a little more power than recommended is always better in amplifiers.

  • February 17, 2012

    any circuit available which converts from 60 W audio o/p with 16 ohms res to 150 Watts 16 ohms.

  • Tmaxx226
    February 14, 2012

    seetharaman,

    Will a 300VA 30-0-30 toroid transformer produce enough power for a stereo application of the amplifier? Or would it be best to use a 500VA transformer? Thank you for the help!

  • February 13, 2012

    Hi Sir,

    I have done my 150W amp as per ur instructions and its working gr8.

    Sir, now i going for subwoofer low pass filter shown in http://www.circuitstoday.com/subwoofer-amplifier

    But, as per ur suggestion for 0.18uf(C1)we can use 0.1uf & 0.082uf in parallel. So,please let me know which type capacitor i can use for 0.082uf? Is it disc type?
    Thanks again…………. Have a nice day..Happy valentine day….

  • February 13, 2012

    Hi Sir,

    I have done my 150Watt AMP as per your instructions and its working fine.

    Thanks for your help.

    I want to assemble subwoofer low pass filter shown in http://www.circuitstoday.com/subwoofer-amplifier
    But, i didn’t get 0.18Mf(C1)in market.So,
    As per your suggestion for 0.18Mf we can use 0.1Mf+0.082Mf.
    So, please let me know 0.082Mf is which type of capacitor? Is it disk?

  • seetharaman
    February 11, 2012

    Hi Jam +45volt should get connected to TIP142 collector and -45volts sholud get connected to TIP147 collector. zero should be connected to terminals shown as earth. (speaker’s one end, C3, R7 and input common terminal)

  • jam
    February 10, 2012

    hi sir, just wanna ask.. on the circuit proper, where should we connect all of the ground? and also, should the -45V be connected with the grounds as well? pls reply. thanks.

  • T0C
    February 9, 2012

    One last (possibly stupid) question.
    I’m making it with 2n3055/MJ2955 darlingrons. Their rated power is 116W 60V 15A, the rating of the TIP147/142 is 100V 10A 125W, so will there be any drop in the output or will it increase/remain the same (my guess is drop)? Or will the output impedance handling change? (Will be used as a driver for a sub, the sub is 250W rms 4 ohm). I’ll be using a 45-0-45 ~10A supply.
    Thanks in advance.

  • Boogie
    February 7, 2012

    I assembled two units for stereo but every time i test it, one unit blows!!! I tried to separate their power supply but still the same…( I already busted 10 pairs of TIP142 and TIP147) I continued troubleshooting but I can’t find any defect in the circuit,The latest part replacement of the Darlington pairs were OK, I guess I must have bought fakes TIP 142 & 147….
    The sound is good. I used this this Ckt. to drive my Subs and center speakers….. I’ll send some pictures later….

  • seetharaman
    February 5, 2012

    Hi Rush the PCB shown is perfect the layout is also correct you can go ahead.
    Hi Panos the maximum output with +42-0–42volts DC can produce 200watts into 4 ohms load.
    Hi Noel 4700uF can be 63volts DC or more. C1 & C2 & C3 can be 25 volts
    HiToC use 2N3055 MJ2955 with BD139 and BD140 as darlington.

  • noel
    February 3, 2012

    1. can’t u give the condenser What volt in use=4700uf ?v
    =C1,C2=10uf ?v
    =C3=100uf ?v
    2. the transformer 5A can use more then 5amphere?

  • T0C
    February 2, 2012

    Will this work, because i’m too lazy to go out and buy the TIP142,147 now, won’t making it with 2n3055(I know 2n3055 is not darlington but I’ve added another transistor to make it like that also without the other transistor it will work too) darlington do it? (of course 2n3055 with MJ2955)

  • panos
    January 28, 2012

    hi ser,i am panos from greece and i want you to tell me the maximum rms watage i can take of this amplifier.

  • samshith triprayar
    January 19, 2012

    hi sir,
    i try this amp. I’am very sad this is not woking.
    D1 and D2 and R5and R3 is very very hot

  • jambebe
    January 15, 2012

    sir .. for this circuit that you posted is it necessary or do we need to add an preamplifier ? if yes how ? thanks

  • January 11, 2012

    Sir….. If i using +/- 50 volt DC power supply its need to be change R6 value??

  • normzhie
    January 11, 2012

    sir can i connect another pair of tip142 and 147 in a parallel connection. what will happen the rms will be increases? thanks

  • January 9, 2012

    Thanks a lot Sir

    can i refer below mentioned URL.

    http://www.diyaudiotr.com/islecler/tammetin.php?metinid=6&durum=e#sonyorum

    Thanks again & sorry for continues asking questions to you……

  • seetharaman
    January 7, 2012

    Hi Rush007 TIP142/147 pair output is limited to 150watts maximum into 4ohms load with +35 0 -35 volts DC and around 100watts into 8 ohms load with +42 0 -42 volts DC.
    BDW83C/84C 150watts into 8 ohms with +52 0 -52 volts DC and 250watts with +48 0 -48 volt DC.
    Since peak current is going to be quite high layout and the gauge of wire used are very important. Please take care.

  • January 7, 2012

    Sir….. actually i want 150Watt RMS(on 8Ohm)& 300Watt RMS(on 4Ohm).
    can i get this by using BDW83C / 84C pair.

  • January 7, 2012

    Sir…How many RMS output can i get from this circuit for 4Ohm/8Ohm woofer with using BDW83C / 84C pair instead of TIP142/147 pair which suggested by you. Have A Nice Day.

  • January 7, 2012

    Thanks a Lot sir………Ur Gr8.

  • Seetharaman
    January 6, 2012

    Hi Rush007 no need for any other modifications, just replace the output transistors with a good heat sink.

  • January 6, 2012

    Thanks very much Sir………but let me know what changes needs to do in original 150W circuit with BDW83C / 84C. Have a nice Day……

  • seetharaman
    January 6, 2012

    Hi Rush007 you have to use >150 watts amplifier for good transient with 150Watts speaker (always use an amplifier with a speaker with less capability, with higher capacity speakers the amp distortion will be transferred to speaker and damage it) . Use DC 50-0-50volt 3amp power supply and use BDW83C / 84C pair for the output, with good large heat sink.
    you can use the sub woofer filter appeared in our projects
    http://www.circuitstoday.com/subwoofer-amplifier
    No PCB layout available you may use standard universal boards.

  • January 5, 2012

    Thanks for response sir…..Request to you please give me suitable sub-woofer filter or sub-woofer output pre-amp circuit diagram for this 150 watt Amp.

    And sir what is the recommended sub-woofer and DC +/- Volt for this 150 Watt circuit because my requirement is to use 12″-150W-8Ohm Sub-woofer.

    Thanks Again sir….. And Wish u Happy New Year.

  • seetharaman
    January 5, 2012

    Hi Basi +40-0–40 volt DC not AC. AC 30-0-30volts
    Hi Rush007 you can use with a suitable sub woofer filter or the sub woofer output of pre-amp / amplifier

  • Rush007
    January 3, 2012

    Sir, Can i use this AMP for my sub-woofer(12″-150W-8Ohm)

    Please suggest me..Thanks.

  • BASI
    January 3, 2012

    Hai seetharaman..
    Plz help me..
    I have used irf250 4 mosft pwr amp volt why..?

  • BASI
    January 3, 2012

    Hai
    40 0 40 AC volt
    DC ???

  • Bryan Laroya
    December 31, 2011

    thank you sir seetharaman……….,i will do your advise…

  • normzhie
    December 30, 2011

    hi, sir thanks. the circuit was great. but if you use 8ohms speaker the output of 150watts rms, it become 75watts rms. in mono. thank you sir you are great.. if you have a 1000 watts rms pls send me thans hers my email normzhie@yahoo.com

  • Malik Umair Latif
    December 29, 2011

    Specify the speaker, How much inches?

  • December 23, 2011

    Power full Amp-
    thanq!

  • seetharaman
    December 21, 2011

    Hi Bose you require smaller clip on heat sink for Q3, and extruded alloy heat sink of around 16sq inches for output transistors Q1 & Q2.

  • gsripon
    December 21, 2011

    this is helpful

  • Bose
    December 20, 2011

    sir is heat sink required for the transistors ?

  • Bose
    December 20, 2011

    thanks seetharaman

  • seetharaman
    December 20, 2011

    Hi Bose you can use 0.47 ohms 5watts resistance. for 4 ohms speaker better use 0.33 ohms, this can be achieved by using 3nos 1 ohm 2 watt resistances in parallel.

  • Bose
    December 19, 2011

    sir i dnt get the resister 0.33 ohm what can i do ,can any other resister is enough or else .33 ohms is required
    thank u,

  • Seetharaman
    December 15, 2011

    Hi Bryan it is working great. please go through all my comments. Q3 should be TIP41 NPN transistor.

  • Goutham
    December 15, 2011

    Oops, finally it was working awesome….
    But there was huge distortion when connected (just connected but not played any music ) to the computer output directly without a pot.
    Is it normal with this Amp or is there any mistake in my construction. I have used 10000uF caps as filters.

  • Goutham
    December 15, 2011

    And I was also tried with 24-0-24 transformer, but the problem still exists.

  • Goutham
    December 15, 2011

    Hello sir,
    I have built this circuit, but when I have checked the output voltage it was displaying around 110 volts at 0 input signal btw I was running on 40-0-40 transformer. when I have connected my subwoofer the diaphragm coming out from its neutral position and stays over there until I turned off the power supply.
    I have rechecked the circuit many times every thing was ok, and replaced all transistors, but the problem still exists.
    Any idea on this.?

  • bryan laroya
    December 15, 2011

    sir can you clarify the Q3?….cause in diagram its TIP41 but in the description above its TIP42!…thats all sir!!!tnx……..

  • BRYAN LAROYA
    December 12, 2011

    CAN I CONNECT A TONE CONTROL HERE SIR?….ACTUALLY I AM FROM PHILIPPINES…………

  • BRYAN LAROYA
    December 12, 2011

    HELLO!….I WANT TO BUILT THIS CIRCUIT….I JUST WANT TO CLARIFY IF THAT CIRCUIT IS WORKING GREAT!??……TNX….

  • Seetharaman
    December 9, 2011

    Hi Pekka Langer you have to use 30-0-30 V RMS AC @ 5 Amps secondary transformer of good quality.

  • Pekka Langer
    December 9, 2011

    And i got it wrong again… not 60-0-60vac.

  • Pekka Langer
    December 9, 2011

    Sorry. i meant 30-0-30 vac and 60-0-60 vac

  • Pekka Langer
    December 9, 2011

    i was thinking about rewiring the secondary on a microwave oven transformer, how many amps would the new cable in the secondary need to be rated for 35+35 vac.
    5A on 35vac or 5amp on 90vac ?
    a fitting transformer around here would cost about 100euros

  • seetharaman
    November 27, 2011

    Hi JRY all ceramics as per PCB are required for the stability of the amplifier. The circuit is the basic one for good quality components and layout. since both are not practicable you have to add these components to avoid the shortfalls

  • maroon
    November 27, 2011

    tanks!
    it’s good circuit!

  • jclv
    November 26, 2011

    it is working as my hope thanks

  • Tomi
    October 25, 2011

    Thanks Seetharaman! That did the trick, I love this amp, works perfectly.

  • jry
    October 24, 2011

    @ seetharaman base on your schematic dia. you have C1 TO C3 but on your pcb layout you have C1 TO C11,, ceramics is not included on your schematic dia. it is nessesary or not

  • seetharaman
    October 23, 2011

    Hi Tomy it looks like crossover distortion. may be at high volues it is sounding clean and at low volumes it is having distortion. If this is your problem, when your out put transistors are highy mismatched this happens, you can reduce this by measuring the output tansistor collector (any one) current and raising it to 50mA, if it is too low by including a 1/2 watt resistace of 10 to 27 ohms between D1 and D2 such that you achieve the results. do not exceed 75mA.

  • Tomi
    October 22, 2011

    Hi Seetharaman,

    I really like the simple design of this. My problem is distortion that is coming out if I try to lower the input signal with any resistors. I’m using this amp to power a 4ohm subwoofer. I have the amp connected to a line level low frequence output of my main amp. I put this amp together based on the exact components that you recommend. I connected 0V to the chassis ground (close to the transformer). I have also connected input common to the same ground point. I’m using 16gauge or larger wires and bus perf board. I can not hear distortion if I don’t use any resistance on signal input. If I try to put 3K normal resitor or 50k pot to the input signal, I get distortion. I have also tried to connect 220PF and 1000PF disk capacitor between the input signal and ground, but no effect. I’m doing probably something obvious wrong, but I just can not understand what that is…

    Your help would be highly appreciated.

  • October 21, 2011

    thanks also to SEETHARAMAN for the ground detail..
    this amplifier is 100%

  • October 21, 2011

    This design actually work..
    I followed every steps and it worked..
    thanks…
    I have now an amplifier that has a very clear output.
    nyahahahaha

  • joy thomas
    October 19, 2011

    Hai sir

    Thanks for your reply

  • seetharaman
    October 18, 2011

    Hi Joy AC RMS X sr. root 2 will be the DC output without load (DC output = V RMS X 1.4.14). With load it dpends on the regulation of the transformer. hence with 32-0-32 you will get 45-0-45 volts DC.

  • joy thomas
    October 18, 2011

    Hai seetharaman

    I woud like the 100 watt rms Poweramplifier, I can use 32 0 32 ac out put transformer, how much dc volt will come the rectifier out put.

    thanking you

  • seetharaman
    October 15, 2011

    Hi Johnda ground should be connected to 0 volt reference supply as there are both negative and positive voltages are used to energise the amp. please refer to amps power supply circuit

  • seetharaman
    October 15, 2011

    Hi Navales you have to use only darlington transistors in this circuit. with regular transistors it will work in low voltage as you raise the voltage the no signal current will increase to full rating and beyond and destroy the output transistors. you have to adjust bias etc, which is a the basics. try to use the published circuits as it is for positive results as the published circuits are well tested.

  • navales
    October 14, 2011

    I have changed the 2 power transistors to a1904 and 5198, a 500 watts power transistor of KONZERT amplifiers then it works to a supply -12 o +12, but during the time I powered it into a -30 o +30 volts… 5A fuse blows… now my question is… what is the difference of tip darlington pair transistor among other transistors? if there is a replacement for that tip transistor that is cheaper than tip… can you please tell me or send it to my email..navalesaryan@yahoo.com. i need your help… thanksssss… your reply is highly needed and appreciated. good afternoon.

  • October 14, 2011

    uhhmm…
    im still new in making amplifiers..
    my problem is the power source..
    where would put the ground?
    I think its not in the negative

  • kilipan
    October 13, 2011

    in this schamatic 150w ampl. the all capacitor did’t swo how much volt u can put?c1,c2,c3……including the power supply c1,c2,c3,c4…..all this capacitor did’t swo how much can put?pleeeseee…….imfom. me…this ergent!!t.Q…

  • nithin
    October 5, 2011

    plese send 2000watts rms amplifier circute diagram
    my mail id

  • seetharaman
    September 23, 2011

    Hi Vash you please refer to my sept 17th comment that site gives you the updated modifications and layout, use them for your success.

  • vash
    September 22, 2011

    can anyone send me a layout on this circuit because i have still dificulties on it i already troubleshoot it but it’s still not working

  • Zahid
    September 19, 2011

    hi

    plz never minde i have not understand in english.
    plz give me a woofer circuit 200w
    easy circuit
    and power full bass controler
    and max speaker 8″ +5″*2
    Thanx all

  • seetharaman
    September 17, 2011

    Hi Navales you can use the following site’s data
    http://pcb.jspayne.com/150wattamp.html

  • navales
    September 17, 2011

    can you please send me a complete pcb layout of this project tip 147. thank you. ( navalesaryan@yahoo.com

  • seetharaman
    September 1, 2011

    Hi NKWENTI there is no protection circuit available for this simple amplifier. you have to take care of speaker impedance(not less than 8 ohms), peak DC supply voltage(+40 and -40 volts should not be exceeded at any time) and loose contacts in speaker connection. you cannot bridge, any mistake will destroy all the transistors may be rectifier and power pack also may blow off.

  • Nkwenti
    August 31, 2011

    Hello.
    I found this site interesting about this amplifier. My problems with the schematic is this, After i assembled the power amplifier in stereo mode, only one channel was working, the other channel only humm and only the TIP 147 gets hot, but as for the other channel, it gives me good sound, also why is it that the amplifier gets damaged very fast??

    Then please i am really interested to build this amplifier in bridge mode, can i just build the amplifier and bridge it just like how TDA 7294 is bridged?? can i please have a simple circuit for speaker protection that can be used with this amplifier??
    Any support will be appreciated.
    Thanks all

  • Andy
    August 20, 2011

    Hi Admin thanks for response the thing is on the output even if I connect them together the positive and negative polarity no distortion sound comes. It should make a disortion sound if amp is alive I think.

  • August 17, 2011

    I like the circuit and i like to build it in stereo.what changes should be done in the power supply(ie;Ampere of the transformer).

  • winston
    August 11, 2011

    hi….since i completed my amplifier,every time i connect 2 60watts speakers i always experience a hum sound whenever i turn the pot to the end but when i only connect one 60w speaker,it does not occur.what should be the problem and what should i do because i really need to connect the two speakers???please help…

  • ARTOIS
    August 8, 2011

    HI ALL
    IVE CLEARED ALL MY PROBLEMS WITH THIS ONE CANT USE A 10K POT ONLY 1K INLINE TO AMP AND IT WORKS GREAT I DIDNT BELIEVE THE SCHEMATIC AT FIRST THATS Y I DID IT TO CHECK FOR MYSELF IM SURPRIZED ITS ACTUALLY A POWER LITTLE AMP FOR THE MONEY IF SOMEONE WANTS A PCB EMAIL ME(ejhgbb@gmail.com).instead of bc558-bc556 transformer 36v-0-36v regulated 50v,otherwise all the rest by the book.txs for a great sight and txs mr SEETHARAMAN for the power supply circuit u send me.
    cheers john

  • artois
    August 7, 2011

    I did this amp but instead of bc558 I used bc556 and I connected a 10k pot but its not working correctly lot of hum I’ve done a few amps with success but this one has me puzzled,are the bc556 the cause used a 36- 0 36 volt trx,iu know its low but even if it pushes out 50w I’m happy.what could the problem be any help pls. When I measure output volt on speaker line I get 42ma but as I turn the pot it goes to 200ma plus then down again.at full volume not bad but down bad. Help pls

  • August 5, 2011

    Hi seetharaman
    i just got the Tip 142 and i am don with this circuit.it is working perfect for me,i love it.
    SEETHARAMAN i must say i am greatful for your asistance.
    Pls can i get the circuit diagram for 12volt car amp with a output of 140watt,pls i need this one so bad.
    I will be waiting tanks

  • winston
    August 4, 2011

    Its a very simple but effective amplifier,completed mine about a week ago and it works great.But the speakers i have are only 60w so instead of putting 220ohms i put 2k to retard output and improve the stability.

  • August 4, 2011

    hi seetharaman.
    Pls want the resistor that can step down 25v,15v and 12v to 3v and 5v pls.
    I will be waiting tanks.

  • July 28, 2011

    ok,seetharaman

  • admin
    July 27, 2011

    Reply to ANDY

    2200 uF/ 16V capacitors are not at all sufficient

    Use the one i shown in the power supply circuit

  • seetharaman
    July 27, 2011

    Hi Cooldon kindly list what is available in your market (even it is not Darling-ton transistor) then i can suggest.
    Hi Vysakh is correct use with 50 volt DC rating.

  • vysakh
    July 25, 2011

    check your rectifier output. If need please add 4700mfd capacitor for filtering

  • Andy
    July 25, 2011

    I am hearing alot distortion. Is this maybe because of the capacitors that I used to the rectifier. The caps are 16v 2200uf.
    Any help please?
    Thanks

  • July 25, 2011

    it’s a simple but huge power amplifier, nice…..

  • July 25, 2011

    Hi seetharaman,
    I am jst coming back from the market,i still can get 2SD2390 (2SB1560,Pls help me i need to biuld this circuit.
    I will be waiting,
    tanks.

  • July 24, 2011

    seetharaman, i’ saw the reply tanks every much

  • July 24, 2011

    WINSTON,i most say tanks man.i am so much greatful

  • July 24, 2011

    i most say tanks man.i am so much greatful

  • seetharaman
    July 24, 2011

    Hi Winston you can use 0.5 ohms 10watts. Maximum voltage is plus minus 45 volts DC. 32-0-32 volts @3amps maximum for unregulated supply.

  • winston
    July 23, 2011

    hi…i was wondering instead of using a pair of 0.33ohms,can i put a pair of 0.5ohms for replacements.And what is the maximum voltage for amplifier?please reply i need to conclude.

  • seetharaman
    July 20, 2011

    Hi Cooldon you can use 2SD2390 (2SB1560 is the PNP pair of this) as replacement. in place of 1.5k one 1k and 470 ohms in series or you can use 3.3k in parallel with 2.7K if available.

  • July 20, 2011

    pls i will be waiting

  • July 20, 2011

    Hi somebody,
    Hi everyone,
    am cris from JOS IN NIGERIA.pls i need somebodys asistants pls.i want biuld this circuit.but when i went to the market to buy the parts they dont have R1 1.5 and Q1 Tip 142 pls i want the replacement for this componet.pls send it to my email,youngcooldon@yahoo.com

  • JAKUV
    July 15, 2011

    I WANT DOWNLOAD ALL FILES BUT FAILED..
    CAN YOU HELP ME..
    I WANT A LIST OF COMPONENTS INCLUDING THE TYPES OF WIRES FOR CERTAINTY..

  • seetharaman
    July 14, 2011

    Hi Andy measure always at the collector of output transistor, connected to positive rail.
    Hi Jakuv
    use the following site PCB drawing includes rectifier and filter capacitors
    http://www.diyaudiotr.com/islecler/tammetin.php?metinid=6&durum=e#sonyorum

  • JAKUV
    July 14, 2011

    HI..
    I WANT A LAYOUT PCB FOR THIS CICRCUIT INCLUDING A POWER SUPPLY..
    EMAIL AT tinytech99@yahoo.com
    PLEASE HELP ME FOR MY FINAL PROJECT..

  • Andy
    July 13, 2011

    Seetaraman thanks for explaining technically but I’m not that technical 🙁 What should I do with my MM to test it? Should I put current measuring on Tip142 base to collector?
    Thanks

  • seetharaman
    July 10, 2011

    Hi Masood try this circuit a proven one.
    http://sound.westhost.com/project101.htm

  • masood
    July 9, 2011

    dear sir,
    this circuit works very well and i salute this circuit .i want a circuit 300w using 2sk1058 and 2sj162.please send me on my facebook alvi.masood251@gmail.com.thanking you.

  • seetharaman
    July 8, 2011

    Hi Andy for a class B amplifier with signal only they should conduct otherwise it should not draw any current theoretically. One output transistor will conduct for 180deg of the input signal and the other balance 180deg. But due to mismatch between the transistors it is not practicable. This will give raise the transfer of conduction from one transistor to other one, may for a small angle both may not conduct. This will start giving crossover distortion.(high volume level will sound ok but very low volume signal will be highly distorted. To avoid this a small forward bias is given to the output transistors (without signal say 50 to 100ma, such that they conduct little over 180deg so there is a overlap between their conduction). This current is called standing current. This is normally measured in the collector circuit of the output transistor without any input signal.

  • mustafa
    July 8, 2011

    required from any one good amplifier circuit + its PCb

  • Andy
    July 4, 2011

    Seetharam what did you mean collector current without any input signal. Can you please clarify?
    I am hearing alot of distortion from my circuit 🙁

  • varma
    June 30, 2011

    Tanx a lot. . .

  • seetharaman
    June 30, 2011

    Hi Verma guaranteed RMS output is >100 watts with 8 ohms speaker and >150watts with 4 ohms load. it is recommended to use 8 ohms speaker as there is no protection circuits used, only simple fuse protection against short circuit of the output is provided.

  • varma
    June 29, 2011

    Wat must be d impedance . . .8 or 4 in ckt it is givn 8 n in description 4. . . . .

  • varma
    June 29, 2011

    Tanx ,n wher can i learn d basics of audio amp

  • seetharaman
    June 29, 2011

    Hi Varma 10″ or 12″ with free cone movement, not a rigid one.
    Hi Andy TIP142 collector current without any input signal.

  • varma
    June 29, 2011

    N can u plz giv me a link wher i can learn basics abt audio amplifiers . . .

  • varma
    June 29, 2011

    Tanx again for ur response ,which kind n size of driver is better for subwoofer using d above 150w ckt. . .

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