it works...lolz
you were right....though
sounds as if someone is strangling Jon Davis...lolz
but who cares...as it it gives me an output....
thnx thnx thnx thnx thnx both of you

 

Congratulations, Baftab, it works! :lol:
Give your little amp some power supply volts, like from a 9V battery and it will be much louder.

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Uncle $crooge

 

okay
i will try 9 volts..AFTER i have my project checked
thnx again

 

Hi Baftb,
Yeah, it's better to be safe than sorry. Your little amp with many parts would be a power-house with a 9V battery and might destroy itself.
I figure that it would have an output into 8 ohms of a whopping 60mW.

Transistor circuits like the 1st and 2nd transistors in your circuit would need a biasing resistor changed to be used with a higher supply voltage than the original 4.5V. Also, emitter resistors could be added to them to cancel some of their high distortion. The collector resistors could be increased in value.

If you were a gambling man, you could re-bias the 2 transistors and try a 36V supply. The little amp with many parts would have an output of nearly 1W, and I think it would not smoke but actually last a while.
You could add emitter resistors to the 1st and 2nd transistors, bootstrap the bias for the output 2N4401 and add negative feedback from the output to the new emitter resistor of the 1st transistor. Then it would sound wonderful, but its gain would be only about 20 so it could amplify very well only the output of a CD or MP3 player.
Your teacher would be very impressed!

Of course you might get addicted to making the little amp work better, and add real power transistors to its output, combining with the existing output transistors to make compound complementary followers. You could also change resistor values to make it better like reducing the value of its output emitter resistors, and increasing the value of its collector resistors. With a 36V supply, it would have an output into 8 ohms of about 18W or about 36W into 4 ohms.

If you really get carried away with modifying your little amp, you could make two of them and connect them in a bridge like the IC I showed.
With a 36V supply, it would have an output into 4 ohms of about 100W! :lol:

Attached Images

baftab_s_36w_amp.gif (15.4 KB, 306 views)

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Uncle $crooge

 

thnx
i have my project checked
now i'll improve it the design you gave is awesome
it'll b like transforming a car into a jet..lolz
sure i'll start working on it from monday...as soon as i get the components
thnx

 

See, now you are addicted to electronics like me! :lol:

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Uncle $crooge