This circuit, to add the ambience effect, was suggested by National Semiconductor in documentation from the 90s. The amplifier needs an appropriate power source.
This low power TTL circuit (Low Power Schottky) can generate rectangular signals on a 10 MHz...
This circuit is from a PopularElectronics of June 1992. The magazine no longer exists, but the...
Any Motorola MC33171 series operating amplifier or equivalent can be used on this 101-gain...