Audio Amplifiers
Electret microphone amplifier circuit
This article describes an compact electret microphone amplifier but you can connect dynamic microphones with low resistance. Electret microphones can be inserted in the same box with the amplifier, it only need 5 to 10V or 9V battery with a current consumption of just 1.5mA.
Here you got the electret amplifier schematic:
Microphone amplifier with low noise
This low noise microphone amplifier is build with MAT02 produced by PMI. This mic amplifier is very performant and has a very low noise level. The amplification can be 20dB or 23.5dB (10x or 15x ) selected by S1.
The output impedance is 70 Ω at 23.5 dB gain and with R3 = 220KΩ the input [...]
40W audio amplifier TDA2030 BD712 BD711
A great 40 W audio mono amplifier build with TDA 2030, BD 712 and BD 711. The output power is 22W on 8 ohm speaker and 40W on 4 ohm. Distorsions are 0.012% at 1khz/8 ohm/11W and 0.032% at 1khz/4 ohm/20W. The IC1 supply curent variates accordingly to the audio input signal so there [...]
