Microphone Preamplifier with BC549C
This compact microphone preamplifier uses the BC549C low-noise NPN transistor to amplify weak microphone signals to line level. It is suitable for dynamic and low-output microphones in audio recording or PA systems.
Circuit Operation
- The BC549C transistor amplifies the input signal from a microphone, providing clean gain with minimal noise.
- Input impedance is designed to match standard dynamic microphones, ensuring proper signal transfer.
- Output can drive line-level inputs for mixers, amplifiers, or recording devices.
Key Features
- Low-noise microphone preamplifier
- Uses BC549C transistor for high-quality amplification
- Suitable for dynamic and low-output microphones
- Compact and easy-to-build design
- Output compatible with standard line-level devices
Construction Notes
- Use high-quality resistors and capacitors to minimize noise and distortion.
- Keep input wiring short and shielded to avoid interference.
- Provide a stable power supply (typically 9V–12V DC) with decoupling capacitors near the transistor.
- Optionally, include a small potentiometer at the input or output for adjustable gain.
