Advice Please on this amp design

[john121]

Hi And thanks for reading.

I have just put together my very first amp and would love some feedback on the circuit. The sound quality is disappointing, works ok, is there anything you can think of to improve performance. Thanks!!
nd make it sound better.

[vintagekiki]

Compare schematics and see what is missing to make your project work properly.

https://www.homemade-circuits.com/mini-audio-amplifier-circuits/
https://makingcircuits.com/blog/1-watt-amplifier-circuit/
https://www.nutsvolts.com/magazine/article/bipolar_transistor_cookbook_part_7
https://learnabout-electronics.org/Amplifiers/amplifiers55.php

[DrGonz78]

What is sound quality? Meaning what source? Musical piece or instrument. What is your expectation from a simple circuit?

[tedmich]

maybe try connecting R2 to C2 like shown here for R2 to C1:

from: https://www.circuitstoday.com/three-...udio-amplifier

this design will never produce much power but that may help!

[Helmholtz]

Just as a side note: All amp designs, where the NFB is connected to the input, have very low input impedance.

[J M Fahey]

Hi And thanks for reading.

I have just put together my very first amp and would love some feedback on the circuit. The sound quality is disappointing, works ok, is there anything you can think of to improve performance. Thanks!!

You already posted this in DIY Audio as the user goodguys
https://www.diyaudio.com/forums/soli...istorting.html
and we told you the circuit was very poor, to put it mildly.
Same about the site where you pulled the schematic from, a poor excuse about an electronics site, again said in a polite way.
And the videos showing this amp.
What did they claim? 100 Watts or something?
Actually 100 milliwatts or thereabouts.

I see you inverted the diodes polarity which were backwards (that alone shows the cluelessness of the "designer") but still many other problems remain.

Your post at DIY Audio:


Get a proper designed circuit and build it.

You can keep the output transistors since they are the expensive part of the circuit,, but you need drivers (they have very low Hfe so canīt be direct driven as shown) , bootstrapping, a proper front end, all combined inside a properly designed circuit.

You were suggested many options but you stubbornly rejected them. WTF????

What i mean is there anything that can be done to my amp to get it working. Please, not alternative designs.
It is a cheap and cheerful project with a bass disortion problem, not intrested in negative feedback or trying to make it a high quality amplifier. Just want it be stable and make sound.

The thread closed there on May the 4th with noresults.
Now you inverted the diodes but keep the same very poor circuit and accepted NONE of the suggestions offered there.
Please do not waste our time here.

This circuit was suggested by user OldDiy, build it , it will work with your present output transistors so you do not waste them:



And you only need 2 resistors and 1 capacitor more than what you have now.

FWIW THIS is the circuit you are trying to build.

A mess , but the grandiose labels and apparent simplicity attract beginners like a magnet:

DIY Amplifier simple 2SA1943 and 2SC5200 Transistor Extremely Powerful Using Output Capacitors

[Pixel]

Hi And thanks for reading.

I have just put together my very first amp and would love some feedback on the circuit. The sound quality is disappointing, works ok, is there anything you can think of to improve performance. Thanks!!
nd make it sound better.

In April of this year you already asked on this forum about this project and received feedback. Please don't waste people's time as the response is going to be the same now as it was then.

[vintagekiki]

#7

In April of this year you ...

https://music-electronics-forum.com/forum/amplification/guitar-amps/build-your-amp/debugging-your-build/930146-amp-distortion-problem
Amp distortion problem

[tedmich]

Wow I guess a forensic investigation (thanks Juan!) was needed to address someone's mental illness, now I'm sorry to have bitten.
We often assume new visitors are acting "in good faith" but that's not always the case.

[DrGonz78]

While reading this post the first time I had deja vu. My next thought was I can't wait to read Juan's response to it.

[The Dude]

Funny Gonz, I was thinking the same thing. Halfway through post #1, I was already thinking, " I hope Juan saw this".

[J M Fahey]

I was SLOW

Had deja vu like all of you but searched DIY Audio for it, didnīt even imagine/remember it had already been posted and answered HERE

Nor that a second try would be attempted.

Maybe this same question has been posted in a dozen Forums all over the Net,"shopping for answers".

FWIW the question (shown in the other thread) about making an amp with a SINGLE transistor (or 2-3 exact same type in paralll) has already been "answered"

Hereīs the latest one from the "Design Bureau":

Technical DIY

17.4K subscribers <-------------

706,740 views (in just 10 days) Jul 1, 2021


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Oh well.

At least the OP is polite