Audio Circuits

Audio circuits had been the first electronics circuits with a practical conception, the necessity to communicate and transmit sounds with higher levels and large distances generates many circuits, since the simple amplifier to the most sophisticated electronic circuit of transmission and captation of long-distance sounds.

Power RMS or average quadratic value or rms (root mean square)

Power PMPO - the level of peak of instantaneous exit relates - Peak Momentary Output Performance.

An audio amplifier is a electronics amplifier , amplifies frequency signals between the 20 Hertz to 20,000 hertz.

The input signal in amplifier can be only some micron-watts output can be ten, one hundred or thousand of watts.

Audio Circuits 

Preamplifier Microphone

Pre Microphone

Tom control

Audio Tom Control circxuit

Audio Line Driver

audio line driver


Audio Amplifier 8W c/ TDA2030

Tda 2030 audio Amplifier

Equalizer 5 Bands

Equalizer 5 Bands
Left to right  60 Hz, 240 Hz, 1 Khz, 4 Khz e 16 Khz. For stereo devices use 2 circuits

Equalizer 3 Bands

Equalizador 3 frequency bands

Vu meter

Vu meter

Headphones Amplifier

Headphone amplifier

Six channel audio mixer

  Mixer have 3 line inputs and 3 micro inputs. Micro have low impedance 200-100R for dinamic  microphones. For an ECM micro we need a serial resistor in line. Internal gain is 2 a 6dB. Line mic have 40dB gain.
Audio mixer table

PWM 30 W

Audio Amplifier 10W - TDA2003

Amplifier 2 x 10W - TDA2009

Amplifier 100W

Amplifier 50W


Controlo Graves e Agudos