Speaker protection circuit

This circuit is made to protect the speakers from the "pump" inconvenience, that is produced in some amplifiers while they are on.

More details

Data sheet

DesignSchema and circuit
ViewNo display
Supply voltage12 Volts
ElectronicAnalog electronics

More info

The circuit, (based on the well-known and versatile NE555) is a timer with a delayed start.

When the circuit is empowered, the integrated circuit delays the activation of the relay connected to its pin 3.
The delay time can be adjusted with the P1 potentiometer. We can increase the delay even more if we increase the value of C1.

The positive output of the amplifiers loudspeakers is connected to the relay’s entrance and its output is connected to baffle.The power of this circuit is 12 volts.

The wiring diagram.

Esquema del circuito loudness

The circuit board.

Circuito loudness

The scheme and the circuit board should be in the same folder and they should have the same name, you should only change the extension to .sch for the scheme and to .brd for the circuit board, this way both of them will be recognized and associated by Eagle.

The file is compressed, to extract it, you should enter a password: www.kemisa.es

If you don´t know how to make a printed circuit boards click here.