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WMD PDO mk.2 & TBVCA – Part 3: PDO as LFO [matttech]

WMD PDO Demo 3


DEMO 08 – Resetting LFOs

For this demo I wanted to demonstrate how well the PDO acts as a resettable/ re-triggered LFO, and investigate whether it could be pressed into use as a pseudo-envelope if the settings were appropriate.

Patch Details

1 – The e350 oscillator was used as a sound source, via the z2040 Lowpass Filter.
2 – All 4 outputs of the PDO (at slow LFO frequency) were sent into 4 inputs of the a152 Quad Sequential Switch
3 – A reset (once a Bar) was sent to: The Trigger input of the Sequential Switch and the Sync input of the PDO (So that each bar the LFO resets, and the waveshape changes)
4 – A different LFO – at a different Phase – was selected for each channel/ output of the PDO….giving the impression of 4 sequentially-triggered envelopes, with differing Attack/ Decay characteristics.
5 – The SUM Out of the PDO is used to control the FM of the e350, and later on the Morph Z. It is also used to sweep the z2040’s cutoff up and down.
6 – The SUM Output of the PDO is also used to FM the PDO itself, which changes the shape of the LFOs. You can hear the FM being gradually increased up to around 01.15 – creating a more “whip-like” effect on each LFO shape. After this the FM is reduced and the shapes return to normal.
7 – Towards the end the PDO’s rate and shapes are experimented with a little.

Some drums were added, largely to demonstrate how accurately the LFOs are resetting each bar.


DEMO 09 – Rhythmically-Triggered LFOs

For this recording I wanted to experiment with using the PDO almost like an envelope generator, with the 4 outputs providing a variety of shapes – depending on the chosen waveform and its phase.

Patch Details

1 – The Synthesis Technology e350 was used as a sound source, via the Tiptop z2040 Lowpass Filter.
2 – The WMD PDO mk.2 (set at its LFO range) was used as the sole modulation source. Its 4 outputs were sent into the 4 inputs of the Doepfer a152 Quad Sequential Switch.
3 – Rhythmic triggers were sent from Silent Way into the Sync input of the PDO (So that on each trigger the LFO resets)
4 – Random gates were then used to switch between the 4 different waves in the Sequential Switch, except for nearer the end, where the same trigger pattern that is syncing the PDO is used instead (this switches through the waves at a much faster speed)
5 – The Sequential Switch output was also sent to control wave morphing on the e350, and the cutoff of the z2040 at various points. In addition it was used to control the amplitude of the final output VCA during parts of the recording.

Bear in mind that you are not listening to the sound of the PDO mk.2 – only the way in which it can be used as a modulation source, to produce rhythmic “envelope-like” effects.