Patch Tips #19 - Morphase

A look at and listen to the Zeroscillator's quadrature outs.



Often overlooked and sometimes misunderstood, the Zeroscillator's morphase function can yield stunning sounds or be used as a complex modulation source.

The outputs offer four phase-shifted versions of the main oscillator (0, 180, 90 & 270 degrees). They can be wave-shaped from triangle to amplitude-compensated square via sine.

This morphing can be manually or CV controlled. A three-way switch determines how the outputs are affected: both, independent, inverse. The CV inputs (A & B) are unattenuated, the manual pots act as an offset.

With the switch left, an LFO patched to 'input A' sweeps the 0 & 90 degree outs from triangle to square and back. With the switch right, the 0 degree output morphs as before, but the 90 degree tap sweeps from square to triangle. With the switch in the middle position, two CVs are required, A & B, for independent morphing.

Here's how it sounds:

zo_morph1
zo_morph2
zo_morph3

Quadrature wave-shaping. 0 & 90 degree outputs panned left & right, dry.

The recordings give an idea of some of the stereo effects possible using just two outputs of the Zeroscillator. Example two features linear FM, while clips 1 & 3 show off one of my favourite patches: zero bias, modulator to FM in. This is another form of wave-shaping and is a great source of plucked string sounds.

The quadrature sines are not as pure as the main out and might need calibration to ensure similar waveforms at similar settings. Of course, as soon as one introduces dynamic wave-shaping, this is less of an issue. The quadrature outs can also be used in LFO mode for panning duties, but you might be better off getting an A-143-9 for this. Aside from the price difference, the QLFO is the best ZO modulator I've found, due to its clean sine and negligible DC-offset.

The Zeroscillator is a complex beast and needs some patience and care. However, the sounds it's capable of are worth the effort.