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WMD PDO mk.2 & TBVCA – Part 2: Textural Drones [matttech]

WMD PDO Demo 1



Whilst putting together a suite of commissioned demos for the WMD PDO mk.2 – and associated Triple Bipolar VCA – some of the recordings turned into extended drone workouts. These are collected within this post.

Further demos, demonstrating the PDO’s deployment as an LFO will be published soon.

For examples of the PDO / TBVCA in use within full compositions, see HERE


DEMO 04 – FM Drone

For this demo I wanted to demonstrate the sound of the PDO when Linear FM is applied to it. Only channel 1 of the PDO was used, and it was set to SINE throughout. A simple drone was set up, with various modulation and manual tweaking carried out during the recording. I was pleasantly surprised at how nice the FM actually sounds – considering that the analogue saw core of the PDO is shaped by a digital waveshaper, and that the Quad Anti-Aliasing Filter was not used.

Patch Details

1 – PDO ch.1 sine was multed to two VCAs, panned left and right, with the amplitude of the VCAs modulated by 2 different slow LFOs.
2 – The Intellijel Rubicon is used as the FM source. 3 different waves are used at various points: Sine, Double Pulse, and -2 Octave Sub.
3 – FM from the Sine and Double Pulse is brought in and out manually, and also via two further VCAs which are modulated by 2 slow LFOs from Maths
4 – Pulse Width Modulation is applied to the Rubicon’s Double Pulse by the SUM output of the Vulcan Modulator LFO (used earlier)
5 – Further FM from the -2 Oct Sub is brought in and out manually at various points.
6 – As the recording progresses the SUM output of the PDO is sent into the Rubicon’s TZFM input, causing FM feedback – which results in a more aggressive and chaotic tone.
7 – The Rubicon’s TZFM and Symmetry are both manipulated throughout, and modulated by further LFOs.


DEMO 05 – PM/FM Drone

For this demo I again set up some drone action, but this time I am using both Phase Modulation AND FM – with a variety of modulation sources used, some of which are also modulated themselves. Some lovely bell-like tones have been achieved, as has some intense aliased Hertz Donut-esque chaotic noise near the end. It is VERY long, but I was happy with the way it turned out as a single, extended jam with no edits….so I’ve left it as it is. After all – that’s what the SKIP function is for! If you are REALLY interested in this module though – especially in terms of its more mellow/ subtle side – I would advise letting it play through, as you may miss some nice little tonal shifts here and there otherwise. Maybe do some ironing or something…or check your emails! Or browse Muff Wiggler……..

Patch Details

1 – All four channels/outputs of the PDO are fed into attenuators and brought in and out manually during the recording.
2 – A subtle LFO is warbling the pitch of the PDO up and down slightly.
3 – PDO Channel 1 is a simple Sine wave for a lot of the recording, although it alters drastically later in the recording once intense Exp. FM is applied from the Rubicon.
4 – PDO Channel 2 is another Sine which is being phase modulated by PDO Channel 1’s Sine, and a Triangle (at a different frequency) from the Rubicon. The patch is set up so that the Intellijel Planar Joystick controls which wave is the modulator. This is achieved by sending its Y CV output into the Triple Bipolar VCA’s CV input, crossfading between the two modulator waves. This has the effect of adding harmonics and overtones to the purer Sine tone.
5 – PDO Channel 3 is set up in a similar way to Channel 2, with two different modulators controlling its phase (PDO Channel 2’s output and a higher frequency Sine from the Rubicon), and the Planar’s X CV output fading between them
6 – Moving the joystick around thus produces a constantly evolving tonal palette, moving from bell-like tones, to Sines, to Saw-like timbres.
7 – TZFM is applied to the Rubicon at various points by a Dixie oscillator, and the Dixie is itself modulated by a Maths LFO. The increased complexity of the Rubicon’s tones thus impacts the PDO’s phase modulation, producing “beating” and dissonant overtones.
8 – The PDO’s timbres increase in complexity again as intense Exp. FM is applied by the Rubicon. The FM is then backed right off to calm things down a little.
9 – The next process to be applied to the PDO is the introduction of a cycling, punchy Maths envelope into the CV234 phase input. This is intensified, and Maths’ Rise and Fall are tweaked until they are up in audio rates, and then brought back down again.
10 – Finally Channel 4 of the PDO is introduced: This is the spiky Triangle wave, and is phase modulated by Channel 3 via an a115 Audio Divider. The various pulse-based sub-octaves in the a115 are brought in and out, and the complexity of the wave being input into it creates some bizarre, clicky timbres. These are further intensified by the re-introduction of savage amounts of Exp. FM.

Like I say, it’s not a musical masterpiece, but will certainly show you some nice timbres.