In this project, we are going to show you how to make a High-quality low noise Microphone Preamplifier Circuit using a TL071 IC. This IC has a low consumption of power due to which it is ideal for projects that require auxiliary power. Microphone Preamplifier Circuit is a low-cost high-performance amplifier with a lot of built-in features. It has short circuit protection along with low noise and low harmonic distortion.
Using this IC rather than a transistor for amplification in the mic preamp state will give a much better distortion filter. All low noise op-amp will be sufficient for this circuit such as TL082, NE55534, etc. This circuit is suitable for a dynamic microphone, condenser microphone with an active circuit inside, or electret microphone that we are using in this project.
The specifications for a microphone preamplifier may vary according to the microphone used to capture the signal and the sound source being recorded. Gain, noise, and distortion are the crucial specifications that should be considered in a preamp.
Hardware Components
The following components are required to make Microphone Preamplifier Circuit
| S.no | Components | Value | Qty |
|---|---|---|---|
| 1. | Op-Amp IC | TL071 | 1 |
| 2. | Electret Mic | – | 1 |
| 3. | Resistor | 10KΩ, 62kΩ | 2, 2 |
| 4. | Electrolytic Capacitor | 10µF, 1µF, 47µF | 2, 1, 1 |
| 5. | Battery | 9-12V | 1 |
| 6. | Breadboard | – | 1 |
| 7. | Battery clips | – | 1 |
| 8. | Connecting Wires | – | 1 |
TL071 Pinout
For a detailed description of pinout, dimension features, and specifications download the datasheet of TL071
Microphone Preamplifier Circuit
Working Explanation
The operating voltage of this circuit is 9-12V, this circuit is very easy to construct with only a few external components.
Resistors and capacitors along with an electret mic are used at the input pins Pin2 and Pin3 of the IC. Voltage is applied at Pin 4 and 7. Another capacitor is at the output of the IC (pin 6) to cancel any noise. If you want to use other ICs in the TL071 series you can but the circuit performance might change a little.
Applications and Uses
- This circuit serves many purposes where low noise and high gain mic amp are desirable. Its main use is to capture a good quality recording of an audio signal. Audio engineers use it to enhance the sound quality of an audio mix.
