---

Window Function

---

Window Function

'Window Function' is used to eliminate the remnant noises contained in 'Sine Sync' wave, and to emulate filter resonance more fully. Window function is itself a kind of Ring Modulation (AM), as the waveform below shows. I suppose that Amplitude Modulation by suitable waves can 'fade out' the loop noise, as it were.


Raw Sine Sync Wave

Modulated by Triangle Window
(Officially, Resonance II)

CZ's usual resonant waves are generated by 'Sine Sync' wave modulated by Sawtooth, Triangle, and Trapezoid wave as 'Windows.' The resonance character is determined by the window wave.

Types of Window Function

There are 5 Window Wave. '*' shows the previously unknown Window Function, which are named by me.

1: Sawtooth
2: Triangle
3: Trapezoid
4: Saw-Pulse *
5: Spike *

I call the last window function as 'Spike', as it adds a spike to the original waveform.

Saw wave (Window: Triangle)

Saw wave (Window: Spike)

Sound Examples

Sounds below is the example of various window functions. They are created by a single DCO, and shares the same settings except the waveform.

Square (Window: Triangle)
Narrow Pulse (Window: Sawtooth)
Sine Sync + Narrow Pulse (Window: Trapezoid)
Pulse (Window: Saw-Pulse)
Square (Window: Spike)
Sine Sync (Window: Spike)
Narrow Pulse (Window: Spike)
Saw + Sine Sync (Window: Spike)

When the original wave is constituted by 2 waveforms (octave modulated), the window affects both waves.
When Spike is used, the DCW does not take effect except for Sine Sync wave. In such cases, the filter, so to speak, is always fully opened.

---

Back Next CZ series

Deep Synthesis: Home
8.30.2002