Rong Mid

A voltage-controlled version of the Nonlinearcircuits Ming Rod, the ring modulator after Tom Oberheim's 1970 AES paper (A "Ring Modulator" Device for the Performing Musician), the diode ring's transformers replaced by transistors working as phase inverters, a differential amplifier passing the sum and difference frequencies while rejecting the signal and the carrier. Here vactrols replace the phase balance pots, so CV controls the balance of inverted and non-inverted signals fed to the diode ring. The SWAP switch changes which sections are controlled, for quite a different palette of sounds. Optional 5V1 zeners keep the output within ±5 V, clipping smoothly.

Key features

• IN R, IN M, CV R and CV M in; OUT
• IN RONG, IN MID, RONG, MID, CV RONG and CV MID knobs
• A SWAP switch
• 8 HP; Nonlinearcircuits publishes no current draw, depth or assembled price (it sells the DIY PCB and panel), and ModularGrid lists none