Wednesday, 10 February 2010

PotD - Ghost Tracks Pt II

Free-running noodles are all well and good, but what if you want more control over the events in a complex patch? Today's Patch of the Day revisits Morton Subotnick's ghost tracks technique, first in its original form using an envelope follower and then MIDI CC > CV automation.



This first recording comprises three multi-track takes. I used a mic patched into an A-119 Ext In/ Env. Follower and fed the resulting CV to different voice parameters e.g. volume, filter cutoff, FM depth, clock VC etc. This involved a lot of barking, howling and clucking into the mic and was a lot of fun.

Nevertheless, this method has its limitations. Firstly, it works best with short, staccato bursts - sustained notes take a lot of breath! You could slew the tail of the envelope, but this alters its original shape. Also, you are limited to a single control voltage. This meant that I found myself reaching over to the modular to alter, say, the pitch of a VCO while bellowing into the mic.

I wanted to be able to play all voices simultaneously and react to the changes dynamically, in other words jam. With just one set of vocal chords and mic/ envelope follower combo, this clearly wasn't going to happen, so I resorted to configuring some MIDI faders and the Aux outs of my Kenton Pro 2000 II.

PotD GhostTrax2  by  navs

This is a live stereo recording of a four-voice patch. Admittedly, this method is a departure from the original concept as the faders & CC/CVs are nothing more than an automation remote control for the modular. However, the movements are recordable and, having the MIDI controllers conveniently in one place, meant I could 'conduct' all voices in the patch.

To add a few unpredictable elements, I cross-multed some of the CVs and audio sources so, for example, a CV that decreased the pitch of one VCO also increased the FM index of another, unrelated voice or, another example, the carrier of a ring mod duo also acted as a modulator in an FM voice.

2 comments:

Brian Biggs said...

Just fantastic as always.

Just Musical said...

you rule! i accidentally played both clips at once and am glad i did!