Be seen from the circuit is quite simple consists of the main equipment are 4 transistor and 5 ics only.
Echo audio circuit.
This is the schematic diagram of echo chamber circuit which will convert the input sound to have echo sound just like if you talking in the cave.
By using a digital echo circuit ic designed especially for the heart to work.
Digital echo processor pt2399 has a very low audio distortion of thd 0 5 and very low noise as well no 90dbv so that the digital echo processor pt2399 is capable of providing good audio quality.
Echo effect is an electronic circuit that is used to delay sound or make an echo in an audio circuit.
Digital echo processor pt2399 to repro echo digital audio system of repro vco delay time system that can be arranged.
Pt2399 echo application circuit the second schematic princeton has on their datasheet is the pt2399 surround delay application circuit.
The working of this circuit.
I believe what they mean by surround is reverb which is actually sort of achievable more on this later in the mods section if you set your circuit up right.
This echo chamber circuit can be applied on any source of audio signal like microphone mp3 player radio etc.
This echo circuit using ic 4558d for additional amplifier and ic pt2399 as a based component.