Pre amplifier using LM358
Components
- LM358
- R1 – 10k
- R2 – 47k
- R3 – 10k
- R4 – 10k
- 1M POT
- C1 -4.7 μf
- C2 – 10 μf
This is a simple mic pre amplifier using LM358. The circuit is self explanatory and is based on LM358 op-amp.
The main function of a pre amplifier is to amplify small and weak signals. The pre amplifier amplifies signal with very high gain but does not have the drive current or current gain to drive the output. hence the boasted signal from pre amplifier is given to power amplifier where the current is amplified. You can connect to amplifier using LM386 described in my previous post or any other amplifier that you have.
Hi Pintu Shaw. Wonder if this would work out with Primo EM184 mic? What is the Volt amount for the mic here? A possibility for 9V supply? Thanks! Juuso
It should work with 9v. You need to replace R1. Replace R1 with 10k VR.
Thanks!