Here the simple audio mic pre amplifier circuit based on single IC LM358. The circuit is very simple, inexpensive and easy to built.
Component Parts List:
R1, R3, R4 = 10K
R2 = 1K
R5 = 100K-1M Potensiometer
C1 = 0.1uF
C2 = 4.7uF/16V
IC1 = LM358 dual op-amp single supply
Mic = Electret Microphone
Notes:
- Use R5 to adjust the gain of op-amp LM358.
- The LM358 has dual op-amp module, you may build stereo audio pre-amp using single LM358.
Download LM358 datasheet here
The circuit designed by Tony van Roon
No. 1 — March 5th, 2011 at 8:36 am
[...] Simple Mic Pre-Amp based LM358 « Circuit Diagram [...]
No. 2 — April 22nd, 2011 at 7:43 am
Hi,
Q1. You have a power supply of 9V in the circuit. Will this circuit work if I have a 5 V supply? If it can, then obviously the values of the capacitors and the resistors would change. Are there any rules or equations that I may need to calculate the values of components if I have a 5 V supply?
Q2. Where does the output of the system go to?
No. 3 — April 22nd, 2011 at 6:58 pm
Q1: Yes, this work with 5V supply. LM358 has a wide rang voltage supply of 3V to 32V. You may try to lower the R1 value.
Q2: The output will be to the mixer circuit, echo chamber, or directly to the tone control circuit.
No. 4 — May 22nd, 2011 at 5:26 pm
hello
i want amplify the weak audio signal. in your point of view which of this op-amp suitable:
lm358 vs 741?
No. 5 — April 6th, 2012 at 3:03 pm
thanks for help