• Skip to main content
  • Skip to primary sidebar

Homemade Circuit Projects

Need circuit help? Post them in the comments! I've answered over 50,000!

Blog | Categories | About | Contact | Calculators-online
You are here: Home / Audio and Amplifier Projects / Hi-Fi 100 Watt Amplifier Circuit Using 2N3055 Transistors – Mini Crescendo

Hi-Fi 100 Watt Amplifier Circuit Using 2N3055 Transistors – Mini Crescendo

Last Updated on December 22, 2023 by Swagatam 205 Comments

Video Demonstration of the Crescendo Amplifier

warning message: electricity is dangerous, proceed with caution

The mini crescendo 100 watt transistorized amplifier circuit explained here was built and tested by me and am extremely pleased by its performance and also its ruggedness as far as maintenance and handling is concerned.

Table of Contents
  • Video Demonstration of the Crescendo Amplifier
  • Amplifier Class
  • Circuit Operation
  • How to Set Quiescent Current
  • Power Supply Circuit

Amplifier Class

Basically, the entire configuration is a symmetrical class A amplifier incorporating an input filter stage, an intermediate driver stage and a powerful symmetrical output stage consisting of the versatile 2N3055 power transistors.

The circuit efficiently drives a 100 watt 4 Ohms speaker with inputs derived from any audio source like a cell phone or DVD player etc.

Before you learn how to build this interesting and useful 100 watt amplifier circuit using 2N3055 transistors, a prior understanding of the involved circuit configuration would be very handy, let’s begin the explanation with the following points:

Circuit Operation

A quick glance at the given circuit diagram makes us conclude that the output configuration is not symmetrical, since the transistors T15 and T16 are both NPN types.

The input stage of the circuit begins or initiates with a symmetrical differential preamplifier stage consisting of the transistors T1, T2 and T3, T4.

T5 and T6 are positioned as the current sources which are further extended as the driver stage consisting of the transistors T7 and T8.

However a closer inspection tells us that of course the wiring is symmetrical, having the transistors T11, T13, T15 at the upper section acting like special booster transistor package.

Similarly the lower section also employs identical super booster stage consisting of the transistors T12, T14 and T16.

The above two sections are perfectly complementary to each other, with reference to the diagram which indicates their emitters being terminated to a common point through the resistors R25 to R27 and via R28 to R30, this effectively that the wiring is exclusively symmetrical by nature.

The output stage is able to produce a massive 200,000 times amplification factor with comparatively very low quiescent current drain.

The quiescent can be set by the adjusting the preset P1.

Due to a non critical nature of the circuit, the entire project can be easily built over a general purpose PCB, however the layout of the components or rather the placement and the ratio of the distance of the components must be kept as identical as possible to the layout of the circuit diagram.

Though a common heatsink may be used for the entire set of the output devices, I personally used separate individual heatsinks for each of the transistors.

This saved me from the headache of using the cumbersome and low efficient mica isolation kit between the transistors.

The inductor is kept for improving the dynamic nature of the circuit. It is built by winding 20 turns of super enameled copper wire over the 1 Ohms resistor itself.

The wire is selected to be close to 1mm in thickness.

Though not absolutely necessary, for better thermal stability the transistors T9 and T11 and also T10 and T12 should be glued together, preferably by attaching the respective pairs face to face.

The quiescent current should be ideally set to 50 mA through the following initial procedure:

60 watt crescendo amplifier circuit

How to Set Quiescent Current

1) Remove the speakers, and short the input terminals (across R1),

2) Connect a DMM set at current range in series with the positive of the power supply to the circuit,

3) Next adjust the preset such that the meter reads an input of 50mA, that’s all, the amplifier’s quiescent current is set and now the connections may be restored for the normal operations of the system.

Power Supply Circuit

The power supply circuit is also shown along side and as can be seen there’s nothing special about it and may be built using the shown ordinary sets of components.

mini crescendo power supply circuit

Parts List of 100 watt amplifier circuit (sh0wn below)

  • R1 = 430 K,
  • R2 = 47K,
  • R3 = 330 Ohms,
  • R4, R5 = 12 K ,
  • R6, R7, R20, R21, R22, R23, R24 = 1 Ohm, 3 Watt, Wire Wound Type,
  • R8, R17 = 68 Ohms,
  • R9 = 100 K, R10, R11, R12, R13 = 5K6,
  • R14, R15 = 12 K,
  • R16, R19 = 100 Ohms,
  • R25 = 10 Ohms / 2 Watts,
  • P1 = 100 Ohms Preset, Linear,
  • C1 = 1 µF / 25V,
  • C2 = 1 n, CERAMIC,
  • C3, C4 = 100PfC5 = 100 nF,
  • C6, C7 = 1000 uF / 35 V,
  • L1 = 20 turns of enameled 1mm copper wire over R24,
  • D1, D2 = RED LED 5mm, All other diodes are = 1N4148,
  • T1 = Matching BC546 pair,
  • T2 = Matching BC556 pair,
  • T3 = BC 557B,
  • T4, T7, T8 = BC 547B,
  • T5, T12 = BC 556B,
  • T6, T9 = BC 546B,
  • T10 = BD 140,
  • T13 = BD 139,
  • T11, T14 = 2N 3055
  • General Purpose PCB,
  • All the transistors T10, T13, T11 and T14 ae mounted on suitable heatsinks

The original design, (courtesy - elektor electronics)

100 watt mini crescendo amplifier circuit

The MOSFET version of the above design can be witnessed in the below given image:

120 watt mini crescendo amplifier circuit

For the complete construction details, please refer to the following link:

Mini Crescendo pdf with PCB and protection circuits 

You'll also like:

  • 1.  Bridged Amplifier Circuit using LM380 Circuit
  • 2.  6 Simple Class A Amplifier Circuits Explained
  • 3.  Make this Musical Greeting Card Circuit
  • 4.  Selecting Power Supply for Car Amplifiers
  • 5.  Touch Volume Control Circuit
  • 6.  Simple Intercom Circuit [2 way]

About Swagatam

I am an electronics engineer with over 15 years of hands-on experience. I am passionate about inventing, designing electronic circuits and PCBs, and helping hobbyists bring their projects to life. That is why I founded homemade-circuits.com, a website where I share innovative circuit ideas and tutorials. Have a circuit related question? Leave a comment.... I guarantee a reply!

Previous Post: « 3 Glittering LED Christmas Tree Light Circuits Explored
Next Post: 4 Automatic Day Night Switch Circuits Explained »

Reader Interactions

Comments

  1. Muzammil says

    October 15, 2024 at 10:52 am

    Hi Sir ,
    Sir I have to design an Amplifier can you help me regarding this ,
    I have to design an Amplifier for a function generator , range 0hz to 15/20MHz (easier to setup)
    2 amp max
    120 volt max with
    100-200watt

    Reply
    • Swagatam says

      October 15, 2024 at 4:07 pm

      Hi Muzammil, you can use the MJE15030 transistor to amplify the signals.

      Reply
  2. Marcos Benedito Freitas Ribeiro says

    December 3, 2023 at 8:42 pm

    Olá amigo, estou fazendo a placa de circuito impresso e logo começarei os testes

    Reply
    • Swagatam says

      December 4, 2023 at 8:48 am

      Sure Marcos, you can build the PCB and test the circuit.

      Reply
  3. Rabiu Ibrahim says

    March 13, 2022 at 1:22 am

    Dear sir please can I add more 2N3055 output transistors for more output power ? I need strong bass even in a low volume is this possible to add thanks so much

    Reply
    • Swagatam says

      March 13, 2022 at 10:13 am

      Hi Rabiu, I don’t think that is possible, you can’t use more number of 2N3055s to increase power in this circuit.

      For powerful bass you can try adding the following circuits:

      https://www.homemade-circuits.com/?s=bass+sub

      Reply
  4. Partha Mazumder says

    January 3, 2022 at 6:29 pm

    Hi, Swagatam,
    Could you please send me the PCB. It will be of real help. Thanks

    Reply
    • Swagatam says

      January 3, 2022 at 8:06 pm

      Hi Partha, you can get all the details along with the complete PCB design under this link:

      https://www.scribd.com/document/502160871/37172068-e014036-155

      Reply
  5. Ravi Sharma says

    May 2, 2021 at 8:20 pm

    Pls give me 6 pair 2n3055transister amplifier circuit diagram and pcb pdf and transformer voltage and amp.

    Reply
  6. Vasile says

    March 28, 2021 at 9:49 pm

    What are the values for R26, R27 and R28? They seem to be added in the schematic later.
    Is the schematic at the latest version?

    Reply
    • Swagatam says

      March 29, 2021 at 11:30 am

      All the schematics are correct and working.
      Those resistors are 1 Ohm 1 watt

      Reply
  7. jayanath says

    September 14, 2020 at 7:12 pm

    Dear sir is this suitable for public address loudspeakers? if yes which circuit should i make?

    Reply
    • Swagatam says

      September 15, 2020 at 9:10 am

      Jayanath, it is suitable, but megaphones do not require H-Fi circuitry therefore can be built with cheaper designs….the above design can be quite expensive for a crude PA audio system

      Reply
  8. Sarbjit Mal says

    October 28, 2019 at 11:08 pm

    Hello Swagatam. While I was considering to construct the mini crescendo original ckt design as published by Elektor Electronics in its Elektor India august 1991 issue titled as “40 watt main amplifier”, I luckily came across your this tutorial where this original ckt have been reproduced. I noticed that to improve the performance you have made some modifications to the original ckt at the input RC network, replacement of zener diodes with LEDs in the constant current circuitry and feedback components. It is evident that you have tried/ tested the original as well as the modified ckt and noticed the improvement in performance parameters. I would like to know to what extent the improvement in terms of frequency response, harmonics distortion, output power, input sensitivity(mV) for rated output(improved, if any). This will help me to decide which ckt I should go for i.e. original or modified. I also noted that the modified ckt uses the same power supply as that of the original ckt. Further, I am sure that you might be having performance parameters as mentioned in the original ckt article published in elector magazine. Still for my satisfaction I am mentioning some of these as below:
    i) Output power 40 Watt into 8 ohm, 60 watt into 4 ohm for a distortion not greater than 0.01% over frequency range 20Hz – 20kHz.
    ii) Max power at onset of clipping is 45 watt into 8 ohms and 65 Watt into 4 ohm load.
    iii) Input sensitivity 800(850) mV for 40(45) watt and 700(750) mV for 60(65) watt into 4 ohm load.
    iv) Frequency response 15Hz – 100kHz within 1 db.
    Therefore, I would like to know about improvement with respect to above mentioned parameters.
    Further, can we expect some further improvement by replacing the 2N3055 connected to -Ve supply rail with MJ2955 PNP transistor ofcourse along with corresponding changes in biasing network to make it fully symmetrical with the upper half ckt around driver and 2N3055 power transistors connected with +Ve supply rail.
    Waiting for early response from Swagatam. Thanking you in advance.
    Sarbjit Mal

    Reply
    • Swagatam says

      October 29, 2019 at 11:24 am

      Hello Sarbjit, All the circuits presented in the above article were taken from Elektor electronics magazine, none of them are mine or modified by me.

      Since these are from the elektor magazine all are perfectly tested and working designs.

      The last design is an upgraded version of the first designs and is rated to work from 250 watts to 300 watts.

      I have little idea whether these circuits can be modified using pnp transistors or not, I recommend not to do it since the original designs are well optimized for best performance.

      Reply
  9. Nagarajan says

    May 24, 2019 at 4:33 pm

    Sir,
    Could you please leave your suggestions for the following:

    I have made 100 + 100 Watt amp using 35-0-(-)35 V Dc.

    Can I drop the DC voltage from 35 V Dc to 12 V DC.

    And this circuit will work in 35 Watts power in good condition.

    Thanks.

    Reply
    • Swagatam says

      May 24, 2019 at 4:42 pm

      Hi Nagarajan, you can do that! It will work as suggested by you!

      Reply
  10. Mihir says

    March 22, 2019 at 2:23 am

    Thanks for such a perfect tutorial….. I made with your guidance of this post…. Here is the video link for my working amplifier….

    Reply
  11. Damir Popovich says

    September 28, 2018 at 11:34 pm

    Please send me the PCB diagram. My email [email protected]
    Thanks. Damir Popovich

    Reply
  12. Siva says

    May 21, 2018 at 5:40 pm

    I built this circuit (in the end) by making the PCB with DipTrace (Used LEDs instead of Zeners). Its working marvelously with Technics Speaker Boxes (as my Technics SU V303 was condemned) Swagatham Sir…. Thank you very much for publishing such a great circuit.

    Reply
    • Swagatam says

      May 21, 2018 at 5:48 pm

      That’s amazing Siva, could you please send a small video clip of your work to my email? I can compensate Rs.200/- for it….
      if only it is possible… not a force…keep up the good work!

      Reply
      • B. SIVA KUMAR says

        June 18, 2018 at 7:11 pm

        Sir,
        Please send your email. I have made a video and send you the same.

        Reply
        • Swagatam says

          June 18, 2018 at 7:41 pm

          Siva, you can send it to
          homemadecircuits
          @
          gmail.com

          Reply
          • Siva says

            June 18, 2018 at 10:34 pm

            Sir,
            I have sent the video to the above email.

            Reply
            • Swagatam says

              June 19, 2018 at 7:27 am

              Hi Siva, I’ll check it soon and let you know!

              Reply
  13. dg says

    April 5, 2018 at 12:13 pm

    This could not work with the schematic with that black bg as is. Like I said. Just take a look at T14 for example, B-E junction? Can’t anyone see anything fishy there?

    Reply
    • Swagatam says

      April 5, 2018 at 1:10 pm

      It’s probably a drawing mistake from me, I have corrected it now, two of them will be 680 ohms and the other one 100 ohms

      Reply
  14. dg says

    April 4, 2018 at 9:35 pm

    the copied schematic on the black bg is wrong. don’t use as is
    no pcb layout?

    Reply
    • Swagatam says

      April 5, 2018 at 6:56 am

      PCB is not strictly necessary if the assembler knows how to solder components on a veroboard. The first design is also correct, it just has a slightly different configuration compared to the last one. All these designs were tested by elektor electronic engineers.

      The last design was built by me on a large veroboard and it worked at the first instant.

      Reply
  15. dg says

    April 4, 2018 at 9:33 pm

    elektor’s crescendo was a mosfet amp, not a bjt based one.

    and this amp is about 50w (on 8 ohms) not 100w, unless it’s on 4 ohms, and then not enough outputs are there and it will eventually blow if pushed a little too much.
    one pair of 3055s on a complex 4 ohms load is asking for trouble.
    pushing the rails above 35V is also pushing the limits as well, unless the 3055s are the most recent made, then they may stand up to some more Vce, but it would be wise to test them for secondary breakdown before using them on rails above 35V

    Reply
  16. Damir Popovich says

    April 1, 2018 at 7:29 pm

    Hi Lancy, will you please send me those PCB designs? My email is
    [email protected] .Thank you.

    Reply
  17. Dowe says

    March 2, 2018 at 2:00 am

    Hello. I am trying to simulate this circuit on microcap and it seems nothing is working. Output is just some nonsense, I think I’m making a mistake that I cant figure out by myself. It really bothers me, Also tried it on Altium. If anybody could help me with that I would be really grateful.
    Just write my an email if you decide to help. [email protected]

    Reply
    • Swagatam says

      March 2, 2018 at 2:32 pm

      Hello, please try the one which is shown at the end of the post…the design has been practically tested with awesome results.

      Reply
  18. rjegadeesan says

    September 9, 2017 at 8:09 am

    fine circuit. can u send pcb diagram .thank u

    Reply
    • Swagatam says

      September 9, 2017 at 8:42 am

      thanks, If possible I’ll try to upload them soon…

      Reply
      • rjegadeesan says

        September 12, 2017 at 6:31 am

        thank u swag.i am very u very much interested of the nice circuit.can u explain why u have included two stage of differential pre amplifying with 547 etc .will one stage pre amplification not it be sufficient adding more stages complicates the circuit .will u give some explanatory note of significance of different pre amplifier transistor ,thus it will provide full understanding of amp circuit working.

        Reply
        • Swagatam says

          September 12, 2017 at 10:51 am

          thanks Jegadeesan, however I will not be able to explain the details in-depth because amplifiers are difficult to simulate in mind.

          Basically the T5/T6 section becomes the constant current source along T1/T2 which supplies the required power to the driver stage T7—T10, while the remaining stage comprising of T11–T15 forms the power amplifier output stage….:)

          Reply
  19. Unknown says

    July 30, 2017 at 3:14 pm

    Can u send the soft copy to my mail id [email protected] pls

    Reply
  20. Japi Roño says

    March 30, 2017 at 4:44 am

    Can this circuit can be inserted with a USB slot?

    Reply
    • Swagatam says

      March 30, 2017 at 12:18 pm

      if the USB slot is able to produce the required minimum level of soundsignal input then the amplifier will work with this input source

      Reply
  21. lima toshi says

    March 24, 2017 at 8:16 am

    Hello Swagatam, i love to try this amp out because i have four 2N3055 just laying around doing nothing(: but sadly this transistors "BC546, BC556, BC557B, BC547B, BC556B, BC546B" are no where to be found on Indian e-commerce sites, so can you please give me an equivalent replacement for the transistors.

    Thank you.
    Regards.

    Reply
    • Swagatam says

      March 24, 2017 at 11:06 am

      Hi Lima, The BC546, BC556, BC557B, BC547B, BC556B, BC546B transistors are one one of the common types of transistors that one can find in any market….it's surprising that you could not find them anywhere….in my place these can be procured in bulk.
      anyway you can use any 100mA or 200mA rated transistor having a 100V as the max V rating in place of these BJTs.

      Reply
  22. Biman Mandal says

    February 8, 2017 at 2:05 am

    I don't remember the specification of these transistor.
    but the circuit was +22 0 -22 volt dual supply (with 18 0 18 CT 3Amp transformer) Can I use 2N3055-MJ2955 ?

    Reply
    • Swagatam says

      February 8, 2017 at 6:17 am

      you can try it but 2N3055-MJ2955 look overrated, you can try TIP31/TIP32 instead

      Reply
  23. Biman Mandal says

    February 1, 2017 at 7:36 am

    I was Constructed a 30W+30W Cassette Deck very long ago, using N055 & P055 Transistor in Golden PCB (Gemini Radio, Chadni Chawk). I get the Circuit diagram from a book of Debashis Bandhopadhyay (ERC publication). Recently all Transistors are burnt out but, I want to repair the Amplifier. I have lost the book. I did not find the Transistor or Circuit Diagram in Gemini Radio. Please give me the circuit diagram of the amplifier of N055-P055. And suggest me where can I find the Transistor or it’s substitute.
    Thanks in advance.

    Reply
    • Swagatam says

      February 1, 2017 at 11:14 am

      Please provide the approximate number of transistors and their sizes (package) used in your design, this will help me to identify a similar kind of circuit for you:

      Reply
    • Biman Mandal says

      February 5, 2017 at 3:43 am

      There are total 8 Nos of Transistor in a single side. 3 Nos BC548, 3 Nos SL100/sk100 and Two power transistor one N055 and one P055 (N055 and P055 are like 2N3055 package TO-3)

      Reply
    • Swagatam says

      February 5, 2017 at 1:16 pm

      It would be difficult to find the exact equivalent of your version, nevertheless you can try the following design

      /blog/2017/01/simple-300-watt-power-amplifier-circuit-using-transistors.html

      you can use only one pair of transistors at the output stage instead of the shown 3 stages.

      Reply
    • Biman Mandal says

      February 5, 2017 at 1:23 pm

      Can you please suggest me equivalent/ substitute of N055 and P055

      Reply
    • Swagatam says

      February 6, 2017 at 4:05 am

      please tell me the voltage and current specifications of these transistors, because these are obsolete parts now and no info is present anywhere.

      Reply
  24. Gurbakhshish Singh Saini says

    January 14, 2017 at 3:20 pm

    This amplifier is the modified version of the original 40+40w amplifier circuit by MD Hull a pioneer designer for Philips nv Netherlands. The circuit has very good bass and treble at very low volumes. I built this amplifier completely as per instructions ( book was published by Norman Brothers in India) in 1990 and is working perfectly to date. I had used only with modification of bd182 with 2n3055. The bass and treble control and the preamp were build and used as were given in book. The bass is far better than the now days used driver driven subwoofers. I had used 0-54v transformer 3A (guru make), dome tweeters*4 of Philips, mid range of 80w and woofers of 10 inch Bolton make with cross over. This whole audio system cost me around 8230rs in 1990's. But believe me even Bose or marantaz or sonos does not compete with it any way in any frequency levels. The bass and treble is very good.
    n
    By

    Reply
    • Swagatam says

      January 15, 2017 at 7:10 am

      Thank you for this interesting update!!

      Reply
  25. Ivan Vukic says

    December 22, 2016 at 2:57 pm

    Whats the max input(audio) RMS voltage?

    Reply
    • Swagatam says

      December 23, 2016 at 3:38 am

      you mean minimum, it's 100mV

      Reply
    • Ivan Vukic says

      December 24, 2016 at 6:11 pm

      No, i mean how much is needed to achive the max power

      Reply
    • Swagatam says

      December 25, 2016 at 11:27 am

      anything between 100mV and 500mV will be enough to get maximum output power

      Reply
  26. Bob says

    December 14, 2016 at 8:35 pm

    how about these sanjeev…C2073 and A940.

    Reply
  27. arheem aly says

    September 26, 2016 at 1:12 pm

    i have question please it can work on 12 v dc ?

    Reply
  28. lan says

    August 16, 2016 at 6:21 am

    Tip 3055.

    Reply
  29. SANJEEV FRANK BROWNE says

    July 1, 2016 at 4:14 pm

    2N3773 IS better to use

    Reply
    • Mr. SANJEEV FRANK BROWNE says

      November 1, 2017 at 9:15 pm

      Dear BOB
      For driver stage transistors BD139/140 can be replaced by 2SC2073 and 2SA940 but it better to use MJE350 and MJE340

      Reply
  30. Ivan Vukic says

    April 19, 2016 at 4:33 pm

    I have made this apm on a protoboard…and for the love of God i cant make it work…the input just gose to the speaker with no amplification and the amp draws 2A, i have used the undmodified circut…i have used bc557c and bc447c insted of the b version, is that a problem?Suplly is +-25V

    Reply
    • Swagatam says

      April 20, 2016 at 4:28 am

      BC447 is not the problem unles it's faulty…the circuit is huge and the fault could anywhere in the design.

      the quiescent current consumption of the circuit without load should be first set to 50mA

      this is done by shorting R1/C1 junction of the amp to ground, speaker connections open, ammeter connected in series with the ground line, and P1 adjusted until the meter reads 50mA

      Reply
      • Ivan Vukic says

        April 21, 2016 at 1:45 pm

        i'll try it on a proper PCB, then we'll see if it works..

        Reply
  31. Rafael Cordano(1BC UTU) says

    March 3, 2016 at 2:28 pm

    Hi,
    could you upload the pcb layout o send it to me to
    Thanks

    Reply
  32. Bruno Ausmann says

    January 27, 2016 at 9:20 pm

    Hi, can you tell me the brand model of this circuit please ? , thank you

    Reply
  33. Bruno Ausmann says

    January 27, 2016 at 9:14 pm

    Hi, I saw this circuit a long time ago, but didnt had the time to actually do it, my question , is the schematic good ? ( i read here that the 2nd photo has some drawing mistakes ) and whats the name/model of the Amplifier, i heard it's crescendo. I have a couple of 2n3055 made in 88" ( i think they are better then the new ones ) also , its the 2n3772 " better " or at least can be used instead of the 2n3055 in this circuit ?, Thank you, sir !

    Reply
    • Swagatam says

      January 28, 2016 at 5:04 am

      Hi Bruno, The circuits are perfect! and will work no matter which one you build.

      2n3772 is good, and can be used instead of 2N3055

      Reply
  34. lan says

    January 14, 2016 at 10:54 am

    Hi Gautam Kumar Goswami.
    Sorry for the delay. PCB softcopy diagrams posted dude. Enjoy.
    Lancy Felix.

    Reply
  35. Gautam Kumar Goswami says

    January 14, 2016 at 8:46 am

    Please send me the soft copy of the PCB layout to my email: [email protected]

    Reply
  36. Christian Beltrami says

    December 27, 2015 at 2:03 am

    good evening beautiful project . it would be possible to have the technical data of the amplifier ? is it possible to have the PCB soft at [email protected]?
    thanks christian

    Reply
    • Swagatam says

      December 28, 2015 at 5:20 am

      thanks, you can refer t the following pdf for more details:

      raylectronics.nl/pdfs/Crescendo_Millennium_en.pdf

      Reply
  37. Rajiv Telang says

    November 28, 2015 at 7:30 am

    Hello sir. I am constructing this amplifier. Please send me the pcb layout at [email protected]
    Rajiv

    Reply
  38. Gautam Kumar Goswami says

    November 16, 2015 at 5:15 am

    Hi Lancy Felix, my name is Gautam Kumar Goswami & I am a Hi Fi Buff. I want to build this 2N 3055 based 100W power amp. Kindly send the PCB diagram soft copies to my email id : [email protected]
    Thanking you in advance,
    G.K.Goswami

    Reply
  39. Gautam Kumar Goswami says

    November 12, 2015 at 12:15 pm

    Dear Mr. Swagatam Majumdar, I want to build this amp & for this I need help from you. One is the PCB in soft. Can you please send it to my email id ? I also need a suitable preamp & tone control unit suitable to its specification. My email id is : [email protected]

    Reply
    • Swagatam says

      November 12, 2015 at 1:51 pm

      Dear Gautam Kumar Goswami, you can find all the details in the following article:

      http://www.eeweb.com/project/circuit_projects/300-watt-mosfet-real-hi-fi-power-amplifier

      Reply
    • Gautam Kumar Goswami says

      November 13, 2015 at 8:01 am

      Dear Mr. Majumdar, I requested for the output 2 x 2N3055 based 100W amplifier PCB in soft & its current upto dated circuitry. Please help. My email is : [email protected]. Thanking you in advance,

      Reply
    • Swagatam says

      November 13, 2015 at 3:07 pm

      oh..sorry, it's not available with me at the moment…

      Reply
  40. Gautam Kumar Goswami says

    November 12, 2015 at 12:03 pm

    Please send me the PCB diagram. My email is : [email protected]

    Reply
  41. Marigold Myka Lawas says

    October 7, 2015 at 1:46 pm

    Is this a 2.1 amplifier? Or just mono?

    Reply
    • Swagatam says

      October 8, 2015 at 11:02 am

      It's a mono amp…you'll need of these to get a stereo output

      Reply
  42. Gautam Kumar Goswami says

    August 28, 2015 at 7:34 am

    I am an audio buff. Can you please send me the soft copy of its pcb to [email protected] ? Please help.

    Reply
  43. Abinash Das says

    August 28, 2015 at 3:38 am

    Please Swagatam Sir, Kindly upload corrected diagram for error free and last long daily use of this project.

    Reply
    • Swagatam says

      August 28, 2015 at 6:08 am

      Hi Abinash, who said the diagrams were not correct?…both the diagrams are perfect, however the last one has been tested by me…so you can try that.

      Reply
    • Abinash Das says

      August 29, 2015 at 5:43 am

      Thank you Swagatam Sir, for your quick reply. Please give your email id for share some valuable information with picture about this project. I will expect support like that from you in future also.

      Reply
    • Swagatam says

      August 29, 2015 at 2:14 pm

      Abinash, commenting in the my website is the best way to get in touch with me without fail….for image presentation you can submit it to:

      admin @ http://www.homemade-circuits.com

      Reply
    • Abinash Das says

      August 30, 2015 at 12:47 pm

      Good Evening Swagatam Sir,
      If possible, can you please upload a video in youtube of 2N3055 amplifier you have already made in the year 2000. So we can able to hear sound quality of this Class A amplifier.

      Reply
    • Swagatam says

      August 31, 2015 at 2:12 am

      Good morning Abinash, sorry that won't be possible because it was built and used by me a long time ago, and was later dismantled for some other purpose

      Reply
  44. Gautam Kumar Goswami says

    August 22, 2015 at 12:32 pm

    Hi Khushin Makim, please send me the sof copy of 100 2N3055 PCB. My email id : [email protected]
    Thanking you,
    Gautam Kumar Goswami

    Reply
  45. Anwar Saeed says

    May 27, 2015 at 5:09 am

    please send me the above pcb diagram at [email protected]

    Reply
  46. Aaronz Paul says

    January 21, 2015 at 6:56 pm

    Hi thanks for the info,actually my aim is to build a HI-FI 5.1 home theater system (100 watts in each channel if possible) with tweeter + mid range speakers in 4 of the channels and the rest would be center and sub.So pls advise me what circuit would be the best for this….thanks in advance.

    Reply
    • Swagatam says

      January 22, 2015 at 7:41 am

      You can try the following simpler design, it also has been tested by me:

      https://www.homemade-circuits.com/2012/04/how-to-make-simplest-100-watt-mosfet.html

      Reply
  47. Aaronz Paul says

    January 20, 2015 at 3:38 pm

    Hi, I would like to know if this circuit is used for creating 5.1 channel amp then how many transformer is needed……in other words how do u power this amp

    Reply
    • Swagatam says

      January 21, 2015 at 4:05 am

      Hi, you could use the above circuit along with the following one for getting a proper 5.1 implementation

      https://www.homemade-circuits.com/2012/08/exploring-ic-tda-7560-4-x-45w-quad.html

      Reply
    • Swagatam says

      January 21, 2015 at 4:06 am

      the amp is powered from the shown power supply design and the signal input is acquired from any music system headphone out

      Reply
  48. joseph aliman says

    January 2, 2015 at 10:03 am

    good day can i use a 18-0-18v, 6amp transformer for this amplifier, thanks

    Reply
    • Swagatam says

      January 3, 2015 at 6:26 am

      yes will do…

      Reply
  49. dch says

    December 30, 2014 at 11:40 pm

    Can I build this without any printed circuit board? Or is printed circuitry required?
    It is suggested to stick to diagram layout yet two pairs of transistors are suggested to be glued together. They are in widely different parts of the diagram. How to do this? 'Fold' the circuitry up? Or have long leads to the transistors, putting them above the rest of the circuitry.
    This will be a first project ever for me.
    🙂

    Reply
    • Swagatam says

      December 31, 2014 at 8:00 am

      yes you can do it, because I myself built it on a dot matrix PCB and succeeded in the first attempt…refer to the diagram that's given in the bottom of the article, I think the transistor glueing info may not be correct so don't do it, I'll check and update the correct data soon.

      Reply
    • Swagatam says

      December 31, 2014 at 8:01 am

      OK..the transistor glueing instructions is relevant to the last diagram…I hope you won't have to fold the PCB now:)

      Reply
  50. Evo Khyn says

    October 24, 2014 at 5:21 am

    okey sir. thanks a lot. ill notify you for an update.

    Reply
  51. Evo Khyn says

    October 22, 2014 at 2:47 pm

    sorry sir but im new to potentiometers. should I use the center terminal and one outer terminal?

    Reply
    • Swagatam says

      October 23, 2014 at 4:01 am

      the center lead is the important one, the other one could be any one of the outer two leads.

      Reply
  52. Evo Khyn says

    October 21, 2014 at 3:30 pm

    and lastly sir, this is the schematic diagram which my classmates used. is this the same?

    http://www.brighthubengineering.com/diy-electronics-devices/94189-make-a-100-watt-transistor-amplifier-circuit/

    Reply
    • Swagatam says

      October 22, 2014 at 5:36 am

      yes it's the same circuit

      Reply
  53. Evo Khyn says

    October 21, 2014 at 2:43 pm

    we are also using 100ohm preset trimmer with the middle pin connected to one of the front pins.

    Reply
    • Swagatam says

      October 22, 2014 at 5:34 am

      that's fine…

      Reply
  54. Evo Khyn says

    October 20, 2014 at 12:36 pm

    Good day sir. We already made the amp but without the inductor first because we didnt have the chance to buy today. We have a little problem. the sound was too low. like there was no amplification. but we used a mono jack to connect to our cellphones. maybe it was the problem. or is it something else? we are so close to finishing this project. is there something we can do? we will try to use a 3 pin stereo jack tomorow and short the left and right. will it be okay? thank you sir.

    Reply
    • Swagatam says

      October 21, 2014 at 5:44 am

      Good day Evo,

      do not connect any music at the input just touch it with your finger, it must produce a very loud buzz in the speaker, and a small hisss when the finger touch is removed…..if this is not happening surely there's something terribly wrong with your circuit assembly.

      I built the second design in the year 2000 when I was quite new to electronics, yet I succeeded to get the best response from it at the first attempt….i had used a general purpose board…not even a PCB

      Reply
    • Swagatam says

      October 21, 2014 at 5:45 am

      mono or stereo input is not the problem…the problem is surely in the amplifier circuit itself….

      Reply
    • Swagatam says

      October 21, 2014 at 5:46 am

      by the way make sure to set the quiescent current with the help of the given preset in the amp….otherwise the circuit will waste a lot of power unnecessarily.

      Reply
    • Evo Khyn says

      October 21, 2014 at 10:56 am

      yes sir. i can hear a buzzing sound but not that loud. and i can also hear a little hiss when i turn the amp on. but the sound is not that loud.

      Reply
    • Evo Khyn says

      October 21, 2014 at 1:08 pm

      and can the V+ and ground terminals of the P1 interchangeable?

      Reply
    • Swagatam says

      October 21, 2014 at 2:11 pm

      it should be very loud, the vibration on the speaker cone should be very high and visible to eyes…something may be not correctly done or the components may be faulty

      check and set quiescent current as explained in the article.

      Reply
    • Swagatam says

      October 21, 2014 at 2:40 pm

      presets do not have polarities, just use the center lead and any of the outer leads of the preset for the connections….. anyway round…the other outer lead can be left open or unconnected

      Reply
  55. Evo Khyn says

    October 19, 2014 at 6:36 am

    Okay sir. Thanks a lot. I'll notify you as soon as the amp is done.

    Reply
  56. Evo Khyn says

    October 14, 2014 at 5:05 pm

    i think the line is an excess sir. thank you very for your help.

    Reply
    • Swagatam says

      October 15, 2014 at 4:59 am

      the extension from R12 ground towards left is a drawing mistake, rest everything is correct in the first diagram.

      Reply
    • Evo Khyn says

      October 15, 2014 at 6:10 pm

      Good day sir. I already decided to make the original version and currently building it. My only concern is that my transformer is only around 21-0-21 and after the rectification it goes up to 28-0-28. It would be good to the new amp design but in the original it indicates around 30 to 35v input. Im a little under voltage. Will this be a problem?

      Reply
    • Swagatam says

      October 16, 2014 at 6:12 am

      Good day evo, there won't be any technical problem if the voltage is decreased, the wattage of the amp will decrease proportionately…. that's all .

      Reply
    • Evo Khyn says

      October 16, 2014 at 12:31 pm

      thank you very much for your help sir.
      I would also like to inform you that my classmates had a problem with the new version of the design. the LED on the upper part wont turn on, T13 explodes and C7 is connected on the wrong terminal. The first time they turned it on, C7 exploded. I think its because the positive terminal of the capacitor is connected to the negative of the power supply.
      That's why I decided to make the original version. I'll also update as soon as I finish this project. Thank you very much sir Swagatam.

      Reply
    • Evo Khyn says

      October 16, 2014 at 4:15 pm

      One last thing sir, in the original design, there are C3, C4 and C5 connected in parallel with 820nF each. We have a difficulty in resources here so I cant find an 820nF. But when the three are added, they will have a sum of 2.46uF. The nearest capacitance I can buy is 3.3uF. And I have no choice but to change the three capacitors with one 3.3uF. Im just not sure if this is still okay. I apologize sir but I'm new to this. You've been a great help.

      Reply
    • Swagatam says

      October 17, 2014 at 2:33 am

      Evo, the new version is also correct except C7 which needs to be reversed and R12 ground side short, except these two drawing mistakes all seems right in the diagram.

      connecting 3 in parallel will have other benefits but you can also try a 3.3uF instead it would do any harm.

      Reply
    • Evo Khyn says

      October 17, 2014 at 1:31 pm

      Good day sir. I used 4 capacitors for the parallel connection with 560nF. their result will be closer to the sum of 3 capacitors of 820nF. I havent tried it yet coz I have a difficulty having the result of 4-6uH for the inductor and my potentiometer broke. thank you for your help sir.

      Reply
    • Swagatam says

      October 18, 2014 at 4:45 am

      Yes it will do…

      for the inductor simply wind any moderately thick magnet wire over the resistor itself….wind 20 turns.

      Reply
    • Evo Khyn says

      October 18, 2014 at 10:45 am

      do you mean i'll put the inductor on top of the resistor? or wrap the resistor? sorry sir coz im a little confused. then connect their legs in parallel. thank you sir. I still have to wait until monday to resume making the amp. thank you very much sir for your non stop help.

      Reply
    • Swagatam says

      October 18, 2014 at 4:11 pm

      yes that's right, wind the copper wire directly over the resistor and then solder the leads (resistor and the coil) together across the given PCB holes.

      Reply
  57. Evo Khyn says

    October 13, 2014 at 1:49 pm

    this part sir, at the picture. the horizontal line.

    http://www.4shared.com/photo/D7dy-2CJba/amplifier-100-watts.html

    thank you for the response.

    Reply
    • Swagatam says

      October 13, 2014 at 3:22 pm

      Evo, please go with the following diagram, it's the original one and is more correct:

      4.bp.blogspot.com/-6H3usY45JAM/UThb0mHH85I/AAAAAAAADdU/wNpmxml3ph8/s1600/100+watt+amplifier+circuit.jpg

      Reply
  58. Evo Khyn says

    October 11, 2014 at 12:09 pm

    good day sir. I am currently making this circuit. I just have a question. At the bottom left, is there really a connection under R12? I just notice that there was an excessive line going to the left and it is not like the one on the top left. I am just confused because if they are really connected, then the non-connected lines between R14 and R19 are useless. Can you please clarify sir? I will wait for your response to be able to continue the build. Thank you.

    Reply
    • Swagatam says

      October 11, 2014 at 2:57 pm

      good day Evo, i can't see any extra line anywhere, R12 and R11 rails seem exactly symmetrical…did you click the image to enlarge?? please click it to enlarge.

      R14 and R19 are wide apart, they have no link at all…I hope there's some confusion in reading the diagram from your side…enlarging it will clarify it

      Reply
  59. Evo Khyn says

    October 10, 2014 at 5:07 pm

    Good day sir. Could you please send me a copy of the PCB layout. Thank you very much.
    [email protected]

    Reply
    • Evo Khyn says

      October 11, 2014 at 12:12 pm

      And I also noticed the power supply circuit. Is the output going to be 25V/5A? Coz I can see a 30V on the bottom left. thank you sir.

      Reply
    • Swagatam says

      October 11, 2014 at 2:59 pm

      power supply outputs will be +25 0 -25V dual supply but after rectification it could well become +32 0 -32v

      Reply
  60. Bhupender Dhawan says

    July 26, 2014 at 10:14 am

    Hi Swagatam sir

    please send me the above pcb diagrams.

    my email id: [email protected]

    Reply
  61. Admin says

    June 10, 2014 at 6:01 pm

    can we use tip or mje 3055 in place of 2n 3055 and which will be better

    Reply
  62. Swagatam says

    May 16, 2014 at 9:45 am

    will require too many modifications,…

    Reply
  63. Admin says

    May 15, 2014 at 2:46 pm

    Is it possible to convert a existing 2n3055 based amplifier into a mosfet one.

    Reply
  64. Admin says

    May 15, 2014 at 2:43 pm

    can we use MIC 6A4 diode in power supply.

    Reply
  65. panzac5 says

    April 27, 2014 at 6:54 pm

    Hi from Athens, could you please send me the PCB layout for this amplifier.
    My email is [email protected]
    Thank you very much

    Reply
    • Swagatam says

      October 11, 2014 at 8:17 am

      sorry, PCB layout is not available…….

      Reply
  66. kanagaraj kanagu says

    April 22, 2014 at 1:08 am

    sir i need regulator power supply for luxion 1watt led i want to connect 8 led's input voltage 24v

    Reply
    • Swagatam says

      April 22, 2014 at 12:31 pm

      use the following circuit

      https://www.homemade-circuits.com/2013/06/universal-high-watt-led-current-limiter.html

      Reply
    • kanagaraj kanagu says

      April 24, 2014 at 3:50 am

      thank you sir

      Reply
  67. Jannick Svejstrup says

    April 19, 2014 at 8:26 am

    I adjusted the P1 with an multimeter in series with (+) to the power supply, but no matter how much I djusted the 100Ohms preset, it only showed around 3-5mA

    Reply
    • Swagatam says

      April 20, 2014 at 4:29 am

      there's something not correct in your circuit, check all the connections many times you should be able to locate the fault…I built this circuit some 10 years ago and succeeded at the first attempt.

      Reply
  68. Jannick Svejstrup says

    April 18, 2014 at 5:59 pm

    Hi again

    I have built the amplifier, and i am getting an amplified signal out of the speaker, but it is very quiet, and a bit distorted. I tested the voltage over all the tranistors, and its at approximately 35 volts, except the T7+T8 – they are only showing between 0,1 – 1V. What could I be doing wrong?

    Reply
    • Swagatam says

      April 19, 2014 at 4:07 am

      No, there's definitely something hugely wrong with your connections or the parts.

      Once built and set the output should provide a large amplification, even without any input music you should be able to hear a big Hiss on the speaker.

      did you adjust the quiescent current as suggested in the article??

      Reply
  69. bmx64x says

    April 13, 2014 at 8:41 am

    hi Lancy Felix

    is it possible for you to send me a pcb layout for this amplifier?
    my email address is [email protected]

    much appreciated.

    Reply
    • lan says

      September 8, 2015 at 9:31 am

      posted dude.

      Reply
  70. bmx64x says

    April 10, 2014 at 7:15 am

    Hi guys, could you please send me the PCB layout for this "Crescendo" amplifier. My email is [email protected].
    THank you in advance..

    Reply
  71. Jannick Svejstrup says

    April 6, 2014 at 12:21 pm

    So, ff I measure between;
    + & 0 = 25V
    – & 0 = 25V
    + & – = 50V

    Correct? 🙂

    Reply
    • Swagatam says

      April 6, 2014 at 2:39 pm

      correct!

      Reply
  72. Jannick Svejstrup says

    March 31, 2014 at 8:07 pm

    Okay, thanks again 🙂

    Reply
  73. Jannick Svejstrup says

    March 24, 2014 at 10:36 am

    This looks like a very nice amplifier, thanks for the detailed schematic and items list! I have just ordered the components and I'm excited to get started!

    I have one questin though – I can't seem to figure out the recommended power suppy voltage/current. I'm confused with the shchematic sayin "Tr1, 2 x 25" Do I need a dual transformer, or?

    If I only need one, will 30 Volts at 5 Ampere be suficient? Can less do it?
    Im planning on winding my own transformer, so no need for "standard values" 🙂

    Reply
    • Swagatam says

      March 25, 2014 at 1:21 pm

      Thank you!
      The transformer needs to be a center tap transformer, that is with two sets of winding on the secondary, rated as 24-0-24V at 2amps or more.
      you can use a transformer rated at 30-0-30V/2amps also.

      Reply
    • Jannick Svejstrup says

      March 29, 2014 at 11:31 pm

      Thank you very much. If I want to make 2 of these amplifiers, one for each channel, can i just make two identical amps and ground them to the same "0" on the transformer (offcourse with twice the current), or do I need 2 seperate center-tapped windings with their own respective "ground/0"

      Reply
    • Swagatam says

      March 30, 2014 at 7:28 am

      separate power supplies won't be required, you can use the same supply, just by making the grounds common…

      Reply
    • Swagatam says

      March 30, 2014 at 7:29 am

      (+) ans (-) supply lines will also need to be joined as common rails for both the units….

      Reply
  74. Pramod Manuja Wickramasinghe says

    December 18, 2013 at 2:54 pm

    how can i contact you for a personal matter immediatly pleaseeeeeeeeeeee

    Reply
  75. Pramod Manuja Wickramasinghe says

    December 14, 2013 at 9:15 am

    in our city there was a young man. he makes subwoofers in home and sell them. but i dont have money to buy that. he has many types of subwoofers. like 5.1 , 2.1 , 7.1. now he is not here. but i want to make one. quality bass sound subwoofer circuit diagram. thats what i need. if you have that send me. i will give my email. thankz

    Reply
    • Swagatam says

      December 14, 2013 at 2:53 pm

      presently i do not have it, i'll try to post in soon and let you know.

      Reply
    • Pramod Manuja Wickramasinghe says

      December 15, 2013 at 5:01 am

      ow do you have above amplifire pcb diagrame?

      Reply
    • Swagatam says

      December 16, 2013 at 5:29 am

      sorry, presently the pcb design is not there with me…

      Reply
    • Swagatam says

      December 17, 2013 at 7:13 am

      I have seen your link, yes you can use it with the above circuit

      Reply
    • Swagatam says

      December 17, 2013 at 7:21 am

      …and please do not include external links, i'll just keep deleting them.

      Reply
  76. Pramod Manuja Wickramasinghe says

    December 14, 2013 at 9:07 am

    do you have is there any subwoofer circuit schematic. if you have please send me. Because i want a good bass. thats what i like

    Reply
    • Swagatam says

      December 14, 2013 at 2:50 pm

      I'll try to include it soon in this blog and give you the link….

      Reply
  77. pramod anuja Wickramasinghe says

    December 12, 2013 at 2:50 pm

    what is the correct swg for the L1 coil

    Reply
    • Swagatam says

      December 13, 2013 at 5:26 am

      20SWG

      Reply
  78. pramod anuja Wickramasinghe says

    December 12, 2013 at 2:48 pm

    is there a good quality bass in this amplifire.

    Reply
    • pramod anuja Wickramasinghe says

      December 13, 2013 at 2:41 pm

      please tell me

      Reply
    • Swagatam says

      December 14, 2013 at 5:05 am

      No, it does not include bass control, you will have to add it externally

      Reply
    • Pramod Manuja Wickramasinghe says

      December 14, 2013 at 9:04 am

      no no I mean the sound. can i get a good bass sound from this

      Reply
    • Swagatam says

      December 14, 2013 at 2:44 pm

      you can get god bass only after including a bass/treble circuit at the above amplifier input

      Reply
  79. pramod anuja Wickramasinghe says

    December 12, 2013 at 2:47 pm

    i00.i.aliimg.com/photo/v0/309836240/TIP3055_Power_NPN_Transistors_ST.jpg

    img.bhs4.com/fa/d/fadf150f65b8acbacfb586f7ab802d0a80dced83_large.jpg

    checkout this links and tell me the witch transistor is good for this circuit. please some one send me the PCB soft copy. upload that and give me the download link.

    Reply
    • Swagatam says

      December 13, 2013 at 5:25 am

      as mentioned in my previous comment, both the transistors are good and rated almost equally, it depends which one you prefer as per your convenience.

      Reply
    • pramod anuja Wickramasinghe says

      December 13, 2013 at 2:40 pm

      i00.i.aliimg.com/photo/v0/309836240/TIP3055_Power_NPN_Transistors_ST.jpg

      then can I use this transister

      Reply
    • Swagatam says

      December 14, 2013 at 5:04 am

      yes you can use them, be sure to add large finned heatsinks to them

      Reply
  80. Swagatam says

    December 11, 2013 at 4:35 am

    The value of L1 has been updated in the parts list.

    Reply
  81. Pramod Manuja Wickramasinghe says

    December 10, 2013 at 5:47 pm

    please some one send me the PCB soft copy. my email- [email protected]

    Reply
  82. Pramod Manuja Wickramasinghe says

    December 10, 2013 at 5:44 pm

    can you send PCB soft copy to my mail:- [email protected]

    Reply
  83. Pramod Manuja Wickramasinghe says

    December 10, 2013 at 5:29 pm

    can you post a completed circuit with all parts

    Reply
  84. Pramod Manuja Wickramasinghe says

    December 10, 2013 at 5:09 pm

    there are 2 types of 3055 transistor. first one is 2N3055 and other one is TIP3055. TIP3055 is a big transistor. 2N3055 is like a normal transistor. which one is good for this amplifier. I cant understand the L1 . How can i make it in home. I'm stuck in this plese reply me soon.

    Reply
    • Swagatam says

      December 11, 2013 at 5:27 am

      Both the transistor types are almost identical with their specifications, only the package is different.

      You can use any of these as per your convenience….I have updated L1 data in the parts list.

      Reply
  85. sagar rathi says

    November 24, 2013 at 12:22 pm

    Would it be okay if i use all the smd component instead of through hole component ,can my circuit behave diffrently under smd components ????

    Please answer ……

    Reply
    • Swagatam says

      November 25, 2013 at 2:16 pm

      yes you can use SMD, the circuit will work perfectly with them too, no issues.

      Reply
  86. Swagatam says

    October 29, 2013 at 4:45 am

    That's great support Lancy, Thanks very much.

    Reply
  87. Swagatam says

    October 28, 2013 at 3:55 pm

    Don't use passive filters, use active filters as it will enhance the effects rather than deteriorating.

    You can use the circuit IC2A/B section of the circuit shown in this link, use it in between your amp and music input:

    https://www.homemade-circuits.com/2012/01/how-to-make-your-own-active.html

    Reply
  88. kanagaraj kanagu says

    October 11, 2013 at 4:53 am

    what is the different between digital ground and analog ground and how to joint these two grounds

    Reply
    • Swagatam says

      October 11, 2013 at 11:54 am

      it's a big explanation, cannot provide it here….these grounds are intended for providing discrete paths for analogue and digital signals, they should not be joined.

      Reply
  89. kanagaraj kanagu says

    October 5, 2013 at 1:30 am

    sir i want buffercircuit & bass boost circuit using op amp

    Reply
  90. kanagaraj kanagu says

    September 28, 2013 at 5:11 pm

    sir hoe to cut below 80HZ in low pass filter circuit

    Reply
    • Swagatam says

      September 29, 2013 at 2:02 pm

      By carefully adjusting the 22k presets.

      Reply
  91. Swagatam says

    September 24, 2013 at 2:11 pm

    Hi Kanagaraj, You can make this circuit:

    https://www.homemade-circuits.com/2012/02/how-to-build-automatic-6-volt-12-volt.html

    replace the feedback 1K resistor with 100k pot and remove the series 1N4148 diode.

    Reply
  92. kanagaraj kanagu says

    September 24, 2013 at 2:11 am

    sir i want one automatic battery charging circuit (12v) i want that circuit automatically sence low battery and start charging and cut the charging when the battery is full

    Reply
  93. kanagaraj kanagu says

    September 20, 2013 at 4:10 pm

    sir hoe to increase left right bass depth without using tone controles (only using pre amplifier) if you have any circuit like that give me

    Reply
    • Swagatam says

      September 21, 2013 at 6:47 am

      You can replace the preamplifier with this circuit, it will work as both preamp and low pass filter:

      https://www.homemade-circuits.com/2013/06/make-this-low-pass-filter-circuit-for.html

      Reply
  94. kanagaraj kanagu says

    September 17, 2013 at 5:07 pm

    do you have any sub woofer pre amplifier circuit for this power amp if you have mean's wiil you please send me ([email protected])

    Reply
    • Swagatam says

      September 18, 2013 at 7:49 am

      You can use the following circuit, just add a low pass filter at the input of the amp:

      https://www.homemade-circuits.com/2012/04/how-to-make-simplest-100-watt-mosfet.html

      Reply
    • kanagaraj kanagu says

      September 19, 2013 at 3:29 pm

      Thank you sir,and i want single supply transistor power amplifier circuit I have o-24 transformer 5amps

      Reply
    • Swagatam says

      September 20, 2013 at 12:24 pm

      I am sorry kanagaraj, I do not have any such circuit presently in my blog, I will try to update it if possible soon.

      Reply
  95. Swagatam says

    September 11, 2013 at 4:55 am

    Thanks for the help Lancy, keep it up mate:)

    Reply
  96. sudesh singh says

    July 28, 2013 at 9:29 am

    Sir,
    I want to made this audio amplifier circuit. But in the amplifier circuit you show the 25V supply and in power supply circuit there is 30V.
    What is co-relation between them. secondly, I want to known the rating of center tap transformer you have used.

    Sudesh

    Reply
    • Swagatam says

      July 29, 2013 at 4:24 am

      After rectification the voltage may rise upto 30V, but it won't be a problem because the amplifier can handle upto 40V

      Reply

Need Help? Please Leave a Comment! We value your input—Kindly keep it relevant to the above topic! Cancel reply

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

Primary Sidebar

Subscribe to New Circuit Ideas

Categories

  • Arduino Projects (87)
  • Audio and Amplifier Projects (132)
  • Automation Projects (17)
  • Automobile Electronics (101)
  • Battery Charger Circuits (83)
  • Datasheets and Components (104)
  • Electronics Theory (143)
  • Free Energy (37)
  • Games and Sports Projects (11)
  • Grid and 3-Phase (19)
  • Health related Projects (25)
  • Home Electrical Circuits (12)
  • Indicator Circuits (14)
  • Inverter Circuits (87)
  • Lamps and Lights (142)
  • Meters and Testers (69)
  • Mini Projects (46)
  • Motor Controller (64)
  • Oscillator Circuits (27)
  • Pets and Pests (15)
  • Power Supply Circuits (108)
  • Remote Control Circuits (50)
  • Security and Alarm (64)
  • Sensors and Detectors (101)
  • Solar Controller Circuits (59)
  • Temperature Controllers (42)
  • Timer and Delay Relay (49)
  • Transmitter Circuits (29)
  • Voltage Control and Protection (37)
  • Water Controller (36)

Calculators

  • Battery Back up Time Calculator
  • Capacitance Reactance Calculator
  • IC 555 Astable Calculator
  • IC 555 Monostable Calculator
  • Inductance Calculator
  • LC Resonance Calculator
  • LM317, LM338, LM396 Calculator
  • Ohm’s Law Calculator
  • Phase Angle Phase Shift Calculator
  • Power Factor (PF) Calculator
  • Reactance Calculator
  • Transistor Astable Calculator
  • Transistor base Resistor Calculator
  • Voltage Divider Calculator
  • Wire Current Calculator
  • Zener Diode Calculator
  • Filter Capacitor Calculator
  • Buck Converter Calculator
  • Boost Converter Calculator
  • Solar Panel, Inverter, Battery Calculator
  • Wire Current Calculator
  • SMPS Transformer Calculator
  • IC SG3525, SG3524 Calculator
  • Inverter LC Filter Calculator

People Also Search

555 Circuits | 741 Circuits | LM324 Circuits | LM338 Circuits | 4017 Circuits | Ultrasonic Projects | SMPS Projects | Christmas Projects | MOSFETs | Radio Circuits | Laser Circuits | PIR Projects |

Recent Comments

  • Swagatam on Contact
  • KRAB Babu on Contact
  • Swagatam on How Shunt Regulator TL431 Works, Datasheet, Application
  • SA on How Shunt Regulator TL431 Works, Datasheet, Application
  • Swagatam on Timer Based Cell Phone Charger Circuit

Company

  • Privacy Policy
  • Cookie Policy
  • About Me
  • Contact
  • Disclaimer
  • Copyright
  • Videos
  • Sitemap

Social Profiles

  • Twitter
  • YouTube
  • Instagram
  • Pinterest
  • My Facebook-Page
  • Quora
  • Stack Exchange
  • Linkedin
  • © 2025 · Swagatam Innovations