Chromatic Currents Part I

Posted on April 19, 2009 by John CS Keston

Here’s a segment of sound from another GMS video I produced yesterday called Chromatic Currents. Once again I was letting the visuals drive the piece, while I controlled parameters in the GMS. On Sound Globules I used the circle of fourths with probability distributions so that C was the most frequent note followed by F, Bb, Eb and so on. I really liked the rare dissonant pitch making its way into the sequence, so I tried a similar technique for Chromatic Currents. The scale was strongly C minor pentatonic, weighted with the Dorian mode by adding less-likely probabilities for D and A. However, every note that was not part of the scale still had a small possibility of occurring. This led to occasional blue or dissonant pitches in the stream of notes. The possibility of having any note within a chromatic scale occur in the stream led me to the title.

Chromatic Currents

GMS Piece: Dodger of Red Lights

Posted on April 17, 2009 by John CS Keston

Today I decided to see if I could create a version of what I performed at the MAW outing last night, as a streaming video with good quality sound. I opted not to use screen capture software so that all the processing on my Macbook Pro could go into rendering the images and sound. The imagery was created by manipulating a red, LED, bike light near the lens of the camera. The screen was then shot with a second camera while the audio was recorded externally using my PCM-D50.

I built a pentatonic scale using the note probability distribution feature in the GMS. The most likely note was a C followed by D, G, G#, and then B natural. I also used the probability distributions on the durations to get some stumbling rhythms centered around sixteenth notes.

Dodger of Red Lights from Unearthed Music on Vimeo.

GMS Probability Distributions

Posted on April 15, 2009 by John CS Keston

The most recent addition I have made to the GMS is probability distributions for note pitches and durations. The way this works is that the user adjusts sliders from zero to one-hundred for each note in the twelve tone (chromatic) scale.

When note probability distributions are enabled, the randomness is weighted so that notes set to zero will never play while at one-hundred the note has the maximum probability of playing. This way the user can setup any sequence of notes in a scale or chord, then toss in a small (or large) possibility for an altered or dissonant note.

The same is true for duration probabilities except that I have the dotted durations as a separate possibility that is applied to the duration determined by the weighted random function. Here’s an example of the note and duration probability distributions in action with the settings as shown in the image.

GMS Probability Distributions

Leafcutter John Remix Competition

Posted on April 14, 2009 by John CS Keston

ACB contributor, recording artist, educator, one-man-software-house, installation artist, and luthier, Leafcutter John is having a remix competition. Click the image for more details on how to enter the competition. I’d love to be involved, but am too busy with my GMS and other projects at the moment. Hopefully some ACB readers will take this on so I can live vicariously through them. There’s lots of really good remixes already, so get cracking!

GMS Interface Design Using controlP5

Posted on April 6, 2009 by John CS Keston

I spent most of my week long break from teaching continuing development of my Gestural Music Sequencer. I’m not sure if I should call it a sequencer or an arpeggiator. It’s really more like an instrument than either of those. The Gestural Musical Instrument perhaps?

Anyway, it’s far from complete, but I added the ability to toggle sustain on the notes as well a menu to choose from available MIDI device drivers. I decided to use a library for Processing called controlP5 to build the UI controls as shown in the screen grab to the right. All of the controls allow keyboard input, so the application can function while the interface is hidden, only displaying the video.

I’m also planning on adding a function to drop video files into the application to create musical phrases from pre-recorded video pieces. Here’s a section of audio captured from the GMS while attached to the Java Sound Synthesizer Sun Microsystems driver. The default sound for this device is an acoustic piano. You can hear the sustain stop around fifteen seconds in then come back on at the end.

GMS Piano Arpeggio