Ring modulation applies multiplication between two signals, using one signal to modulate the amplitude and polarity of the other through a process often referred to as four-quadrant multiplication (or bipolar amplitude modulation).
With this added as a Voicelab option, many more voices could be possible to recreate. It also just sounds cool.
Typically used in music production but also commonly in special effects for voices, this would give Voicemod users the ability to recreate some of their favourite voices without resorting to programs like Audacity.