Intro

I am studying how IC routing is done in large chips. I am following advice I often give people that it is helpful to learn how to do something by hand before using an automation tool. I was skeptical about this for chip routing because the scale of the problem these routers solve (trillions of gates) is outside what can be done by hand. As it turns out a few of the things I know about routing PCBs helped prepare me for learning some of the conceptual and strategic aspects of what these tools do.

The Anti-Ergonomy of Instruments of Interaction, Freed, Adrian , Stanford HCI Seminar, 09/2010, Stanford, CA, (2010)

Door Bleeper, Freed, Adrian , Everyday Electronics, 10/1975, (1975)

Position is sensed by measuring the resistance of each ring of 16 conductive plastic strips around the bowl. The resistance is lowered as the draped conductive fabric shorts out more of a section of the strip. Pressure is sensed using the piezoresistive fabric strips around the annulus surrounding the bowl. Each piezoresistive strip sits on a segment of conductive fabric taped to the acrylic base. The resistance between this conductor and the ground potential is established by the conductive draped fabric in contact with the conductive gold tape at the top of the bowl.

This alternative to the 555 timer for making audio oscillators is built from simpler building blocks (inverters) and has more versatility. You can find the schematics that correspond to the build video here: https://www.youtube.com/watch?v=CzO_ZKMSnAU

In a recent workshop on e-textile sound for the 2018 e-Textile Spring Camp, I provided a unifying framework for analog and digital sound synthesis and capacitive sensing techniques under the rubric of relaxation oscillators.

The following pages provide context for the workshop and include links to contributions from my co-teacher, Martin De Bie. This includes pointers to various iterations of his 555 timer-based Textilo project.

This project will be expanded ongoingly with further relaxation oscillator schemes.

Commentary proposed for NIME Reader

The fingerphone is my creative response to three umbridges: the waste and unsustainability of musical instrument manufacturing practices, the prevailing absence of long historical research to underwrite claims of newness in NIME community projects, and the timbral poverty of the singular, strident sawtooth wavefrom of the Stylophone – the point of departure for the fingerphone instrument design.

Sound Design as Human Matter Interaction, Wei, Sha Xin, and Freed, Adrian Naveb Navid , SigChi, 2013, Paris, France, (2013)

Symbolic Music Similarity using Neuronal Periodicity and Dynamic Programming, Valle, Rafael, and Freed Adrian , Mathematics and Computation in Music, London, UK, (2015)

Ubiquitous in most DAWs and available in online versions, programmable drum step sequencers have been around since 1972, when Eko released the ComputeRhythm. In our previous research at CNMAT, these drum step sequencers have been expanded to include onset probabilities[1] and rhythmic expressivity [2].

In this work, we address the challenge of learning a drum agent that is capable of learning styles and interpolating between them during performance, taking into account rhythmic expressivity, musical sections and phrases and drum patterns.

We describe a hierarchical solution that learns, from MIDI drum track and annotated data, a drum agent in the format of three probabilistic finite state automata(PFSA). In decreasing hierarchy :

The first automata operates on the sections of the piece; The second automata operates on the phrases and licks; The third automata learns the drum patterns, including the drum pieces used and their respective onset probabilities given time-step and actuator. Each newly learned drum pattern is used to update or create new patterns, dependent on the angular similarity between new and existing patterns. Based on our Control Improvisation approach [3], we design specifications to guarantee that the improvisation and learning process satisfy some desirable properties. For example, from a performer perspective, it is extremely unlikely that a kick drum will be played with the hands or that multiple sequential hits on the same piece will be done with one hand only.

During playback, we interpolate between drum agents by projecting them onto a 2d space using CNMAT’s Radial Basis Function Interpolator, which outputs weights for each drum agent’s PFSA. Sound is generated by reading drum samples and cross-synthesis is used to provide an interpolation between the instruments of each style. We provide examples in which we learn and interpolate between drum kit and tabla examples from pieces commonly associated with rock and and hindustani music.

[1] Vijay Iyer, Jeff Bilmes, Matt Wright, and David Wessel. A novel representation for rhythmic structure. In Proceedings of the 23rd International Computer Music Conference, pages 97–100. International Computer Music Association, 1997.

Batera : Drummer Agent with Style Learning and Interpolation, Valle, Rafael, and Freed Adrian , Study Day On Computer Simulation Of Musical Creativity, 27/06/2015, University of Huddersfield, UK, (2015)