When switching an audio system with audio players, preamplifier and power amplifier on and off via a central switch, loud crackling or even a pop-like noise may occur and be heard from the connected speakers. This is caused by a charge potential passing through electrolytic capacitors in the signal path of the preamplifier when switched on. The EVAB-22 can prevent this unpleasant effect. For this purpose, you insert the device into the signal path between preamplifier (or signal source) and power amplifier. The EVAB-22 delays connection of the signal source to the power amplifier when switching the system on. The turn-on pulse does not reach the power amplifier. When the system is switched off, the signal path to the power amplifier is disconnected immediately, before a turn-off pulse can reach the power amplifier via the signal path.