On The Sensations of Tone VII
CCRMA 220C Project



On the Sensations of Tone is a series of compositions exploring the biomechanics of hearing, spatial counterpoint, and cognitive involvement during the creative process. The pieces are composed using a modular synthesizer, highly directional ultrasonic speakers, computer generated distortion product otoacoustic emissions, and a neurobiofeedback system. The pieces are highly reactive to the listener, and the sounds change dynamically with subtle physical movement.

Distortion product otoacoustic emissions (DPOAEs) are tones the ear makes in response to a specific combination of pure tone frequencies. When the two tones are sounded in speakers, a third tone emerges in the ear and can be recorded by a microphone. Audiologists use DPOAEs for objective measurement of hearing health. By moving one's head, the listener will notice new tones appear, disappear, and change timbre.

Through employing a neurobiofeedback system, cognitive information pertaining to listening, creativity, and improvisation is used to re-influence the overall work. Cognitive involvement during live performance is converted into control data to shape and direct the composition while the piece is performed. The process creates an ebb and flow between musical intention and intuition.

My previous compositions using DPOAEs prior to 220B required careful calculations for each frequency combination, with each pair of tones routed to a specific pair of speakers (else intermodulation distortion would result in the speaker). For 220B I created a class for routing the sound to dedicated speakers, and shorthand frequency pairing system for DPOAEs in the ChucK programming environment. The frequency pairs were assigned variables to approximate a non-repeating "scale" system, with the aim to create large scale work with DPOAE "notes." The system allows focus to remain on the compositional process.

For my 220C project, I will create a seventh entry in my On the Sensations of Tone series of works. The style of this composition will be different than those earlier in the series as the notation system will allow a different treatment of the DPOAEs. This will be a large scale composition, which may also include non-DPOAE sections created by modular synthesis and computer mediated sound generation.

Goals for Weeks 1-5:
-to build a DPOAE keyboard instrument for the 33 specific frequency pairs.
-experiment with DPOAEs in various styles/modes of presentation
-to learn how to use the sound system in the listening room

Goals for Weeks 5-10:
-to compose a large scale composition using DPOAEs
-to record the piece in either stereo or multiple channels in the listening room
-debut the piece in the Spring CCRMA Concert

4-21-14 Progress

-So far this quarter:
-built a monophonic DPOAE keyboard in Max/MSP
-adapted the keyboard for polyphony (4 parts)
-learned how to use the listening room
-discovered the issue that Max/MSP and Jack are not compatible. Max crashes once the DAC is activated when audio is routed to Jack. The (hopefully temporary) workaround is to use analog outputs and a soundcard.

4-28-14 Progress

-I built an ADSR into my keyboard DPOAE Max patch, and troubleshooted triggering issues.
-I tweaked the system so it only responds to keyboard input within the 33-note range using condition logic in Max/MSP
-Began to also build a keyboard DPOAE system in the ChucK programming environment
-Started to experiment with various styles of music using the DPOAE keyboard
-Faced a roadblock of being unable to record the multichannel audio from Max using the same method used in previous 220 classes due to the incompatibility between Max and Jack. I usually routed the audio to Ableton, where I made arrangements and mixed the audio.
-My proposed solution in the coming week is to build a Max patch that can record simultaneous multichannel audio
-built this website

5-6-14 Progress

-since Max/MSP and Jack are incompatable, I worked on other ways to record my multichannel audio from Max, which involved working with Soundflower (got close, but didn't find the solution, it may be incompatable with Mountain Lion), recroding AIFF-C multichannel audio files using sndbuff~ 8, but Ableton does not accpet these files. I also ported the ADSR DPOAE instrument as a Max For Live instrument so I could record directly in Ableton. The mono version works, but due to the inability to have multichannel audio in a single track the polyphonic version does not work. I have a workaround that is close to done, but still needs some debugging. Finally, I just used four stereo sndbuff~ objects in Max and lined the tracks up in Ableton. Still thinking about a better way to do this (probably the Max for Live instrument), but this works for now.
-worked on the composition. Have two recorded sessions of free-form improvisation using the ADSR keyboard. Thinking about compositional structure. Next session I plan to use the version of the instrument without the ADSR, and then add it as a layer.
-Submitted proposal for CCRMA Spring concert. May move my operations from the listening room to the CCRMA stage since that is where the concert will be held.

5-8-14 Progress

-worked on non-distortion product (DP) section of composition. Made field recordings of a spring, edited recordings, constructed two arrangements in Ableton.
-worked with Time Layer granular synth Max for Live pluggin with the recordings and recorded result.

5-10-14 Progress

-compositional process with Max/MSP sndbuff~ felt rigid, so continued to work towards recording directly into a DAW such as Ableton. Found a solution with Rewire. Set up Max driver as ad_rewire and midi port as 1, and in Ableton select Audio From "Max 6" and "1/2" "3/4" "5/6" "7/8" for a multichannel tunnel between applications.
-worked out a series of effective distortion product four voice chords on the keyboard and recorded into Ableton.
-started arranging the chord sequences. Effective, but not as dense as previous works as each channel usually has only one frequency. Worked with layering chords and found interesting results. Sometimes the layering enhances the DP effect, and other times it diminishes it.

5-11-14 Progress

-worked on modular synth section of the compositon. Constructed a patch and recorded 8 channels of audio and multiple takes.
-continued to work on field recorded section

5-12-14 Progress

-continued to develop ear tone session, more arrangement of chord sequences. Started section two by rearranging chords into notes and sequencing patterns. Have multiple takes.
-listened to multichannel modular synth and field recorded sections in the 8-chan. studio.

5-23-14 Progress/CCRMA Concert

-many sessions of cutting the modular synth section and arranging material spatially. Worked with semi-periodic pitch classes and drone in first section, and performed the exponential/linear/logarithmic curve of the envelope for the third section.
-ear tone section:
---arranged a distortion product harmony section.
---arranged a 123,231,312 melodic ear tone section in both the right hand and left hand.
---extended the piches in the melodic section at a specific point, and deleted pitches of the melodic material to create space and alternate rhythm.
-mixed and tweeked the mix
-workshopped the piece with Brian Ferneyhough and Jarek Kapuscinski
--presented the final mix with changes at the CCRMA Spring Concert