Diy Class A Stereo Amplifier step by step

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Hi everyone.

I present to you today a small class A hifi stereo amp project based on :

  • famous power transistors the sc5200.
  • Elna cerafine audiophile output capacitors.
  • Alpine audiophile knob

The sound of this amp is very clear with a lot of current, I tested it with jbl 4430 speakers, the result is very impressive!!

Attached is the complete manufacturing video on my youtube channel where you will find other audio projects.

 

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This appears to be a "how low can you go?" type project, like many posted on Youtube, perhaps just for "me too" status.
How about posting a schematic (circuit) diagram of your project, Homemade Audio, so we can suggest why it isn't worth the time and cost of components to build it. With all the hotmelt glue used to hold it together and wrongly mounted heatsinks, I can't imagine the power in class A operation will knock anyone's socks off anyway.
 
I'm going to play devil's advocate.
I who never watch this kind of video on youtube, I will keep this one for my children.
They don't understand anything about what I do, it's a good opportunity for a concrete project at their level.
just my opinion
 
Piece of plywood. Hot glue for fastening large parts. Connectors for power, input and output. 12v power fuse! 3D montage.
Audiophile capacitors on power supply and output? The amplifier according to the SE scheme is a common emitter at 5200. Bias (nfb) 1k base-collector. Resistive load 2 * 8.2 ohm in series (cement resistors). The output signal is taken from the divider (incomprehensible solution). The speaker is connected through a 1000uF capacitor and a series inductor (?). It makes a sound 🙂
 

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Oh PLEASE!!!!
Not HERE!, not in DIY Audio!

As crappy a design as can be, just like thousands out there bowing to the lowest bidder, only clickbaiting users to get views.

More important: proving sound quality does not come from "parts" (even if "Audiophile" 😱 ) but from design ... in which area you are sadly missing ... to say it politely.

You can´t even solder ... typical of some noobs, you use soldering iron tip as a "brush", "as if solder was paint", while proper is to put it firmly against part to be soldered, to transmit heat quickly, and melt solder on the spot,

EDIT: I´m answering the OP, not OldDiy post which appears just above by sheer chance.
 
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https://sound-au.com/project36.htm " I tested the distortion at 6V RMS again, and measured 1.03% - a worthwhile improvement I thought. Increasing the output to 8V, the distortion climbed to 1.18% ...First step was to set the quiescent voltage with the pot, so I had 1/2 the supply voltage at the drain (I tested the MOSFET circuit first). With an applied DC of 30V, this meant a voltage of 15V, so the current was 1.875A or 28W dissipation (both in transistor and load - for a total of 56W). ...None of this testing has been done with a circuit board. In all cases I simply bolted the device to a heatsink, and attached the other components as required. Power connections were all made using alligator clip leads. Since I have used exactly the same 'rats-nest' wiring for all testing (including these last tests), and I have not been able to induce additional (or reduced) distortion by moving leads about, the amp looks as if it will be fairly tolerant of assembly methods (all known assembly methods will be superior to what I have done so far). 🙂
 

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As much as it is easy to jump on the band wagon and say how crappy this design is, lets have a look at what is presented.

The circuit seems to be connected as follows (ignoring the input pot and 4700u cap across the supply):


1660223314716.png


Simulation at 1W gives this delightful output:

1660223425649.png


This gives a cool distortion figure of:

1660223478761.png


And an FFT that looks like:

1660223551243.png



It is a competently designed circuit that makes a good amp, not 'Audiophile' components.
 
........I don't think he cares whether it works or not. ........
I know I am jaded, but given that the OP just joined that day, immediately did 4 'different' posts with links to 4 of their youtube videos, which aren't new, and nothing else; I'm going to say it is all about hits on the videos and youtube seeing links to the videos. We've been spammed.
 
I've seen some terrible circuits like this on youtube before. "Too good to be true" missing a few components that would vastly improve it for pennies.

The only point to building a circuit like this is to learn. I designed and built circuits like this when I was 10 just to see if they would work, and just to do something with parts I had.
 
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I'll put my two cents in......
Looks like some slop from a 12 year old that found a soldering iron in the trash would make.
"Look Mama!....... I'm a technician!"
Its the 5 minute crafts of audio. Things don't have to work, the videos just have to be relatively short, entertaining to watch and look easy enough that someone will think that they could do it if they really wanted to. It is what works to get views. You'll notice these videos have way more views than the ones where real amplifiers are built.
 
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