Chewy Ring Mod (with on-board carrier) by Swarm Audio published on 2012/08/30 14:20:55 +0000 Another classic passive ring mod circuit. This one includes a built in pulse oscillator carrier wave. Switch between on-board and external carrier signals, in the case of this demo, the external carrier was provided by a Korg Monotron. Controls for oscillator pitch and volume. Oscillator runs for ages off a 9V battery.