Amplifier Output Delay with Relay

This is a minimal circuit which I built to individual of my audio amplifier projects to control the presenter output relay. The end of this circuit is to control the relay which turns on the speaker output relay within the audio amplifier. The impression of the circuit is time lag around 5 seconds ofter the power up until the speakers are switched to the amplifier output to circumvent grating “pound” sound from the speakers. an added appear of this circuit is so as to is disconnects the orator just now once the power within the amplifier is finish inedible, so avoiding every now and then nasty sounds as soon as you trip the equipments inedible.

Amplifier Output Delay with Relay Circuit Diagram

Followed by power is functional to the power input of the circuit, the categorical stage of AC voltage charges C1. Then C2 starts to charge little by little through R1. while the voltage in C2 rises, the emitter output voltage of Q1 rises concurrently with voltage on C2. as the output voltage of Q2 is anticyclone an adequate amount of (typically around 16..20V) the relay goes to on state and the relay witches associate the speakers to the amplifier output. It takes typically around 5 seconds in the same way as power up until the relay starts to conduct (next to absolute epoch depends on the size of C2, relay voltage and circuit input voltage). as the power is switched rotten, C1 force not tied up it’s energy quite quickly. and C2 will transpire charged quite quickly through R2. into excluding than 0.5 seconds the speakers are disconnected from the amplifier output.