Here is an excellent user demo video emphasizing the harmonic nature of the Quaverato: the independent modulation of low and high frequencies. Throughout the vid, the user (Tonal AXiS) manipulates the HARMONIC MIX knob to clearly demonstrate steady lows and pulsing highs, and vice versa. At 0:57 he switches from IN PHASE to OUT of PHASE, and you can clearly hear the sweeping, wah-like effects.
Tonal AXiS Quaverato Demo