az00025
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Does any Know how to design simple Stereo Audio Amplifier(Pre-Amp+Tone Control+Output Stage) by using LM358 op-amp and (8 ohm Speaker) ,the circuit should be working with 4.5V (e.g. 3 AA batteries)...????
I designed several circuits but I got 2 much noise
>>>>one of the circuit that I built is show below(Op-Amp Audio Amplifier)...
However the main two problems that I found are:
1) Too much voltage gain (x300), and a noisy signal reference due to thermal noise from the 1M resistors. Assuming a 20kHz bandwidth I calculate 5.4mV of noise at the output, which is likely to be audible.
2)Another possible issue is instability. RF oscillation sometimes shows itself as excessive audio noise.
I'm experimenting this circuit but unfortunately,i'm still facing these problems.... any suggestion with some details to how reduce excessive audio noise....any help, I will appreciate it..
<<<Does anyone have a solution for these problems?????PLZ>>>..........
I designed several circuits but I got 2 much noise
>>>>one of the circuit that I built is show below(Op-Amp Audio Amplifier)...
However the main two problems that I found are:
1) Too much voltage gain (x300), and a noisy signal reference due to thermal noise from the 1M resistors. Assuming a 20kHz bandwidth I calculate 5.4mV of noise at the output, which is likely to be audible.
2)Another possible issue is instability. RF oscillation sometimes shows itself as excessive audio noise.
I'm experimenting this circuit but unfortunately,i'm still facing these problems.... any suggestion with some details to how reduce excessive audio noise....any help, I will appreciate it..
<<<Does anyone have a solution for these problems?????PLZ>>>..........