SEPTAR V2

In 2011, we set out to ‘hack’ MIDI guitar pickup systems and enable access to the audio outputs of the individual strings of a guitar. These MIDI guitar pickup systems generally sense string activity with piezo transducers, which can be used as accurate microphones if amplified correctly.

A: Resistors R1 and R2 divide the voltage in half. This sets the operating point of the JFET (C). This allows the maximum voltage swing before clipping can occur. These resistors also set the input impedance to a high value required (approx. 1.1 Megohm)

B: Resistor R3 and Capacitor C1 form a low pass filter at 194kHz. To limit the chance of picking up radio interference whilse just above the ‘studio standard’ of 192kHz.

C: This is the JFET. It carries out the impedance conversion duties.

D: Resistor R4 limits the amount of current that is drawn from the battery.

E: Capacitor C2 blocks the battery supply voltage from passing into the output.

F: Resistor Rz is a pseudo-balancing resistor. Its function is to present a resistance to ground that matches the output impedance of the main circuit. This allows better interfacing with balanced equipment that may follow.

rg.ambi~ Ambisonic Abstractions for Pure Data (Pd)

Download Link:

What’s in the .zip?
– Encoders for 1st, 2nd, and 3rd order ambisonic panning
– Based on Furse-Malham (“FuMa”) coefficients
– Decoders for stereo, quad, 5, and 8-channel loudspeaker arrays

Additional Reading:

Find an Error / Bug?
ricky at rickygraham dot net

Divergence Press (Issue 3) – Spatial Sound: Creative Practice in Electroacoustic Music

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Issue 3 of Divergence Press (Centre for Research in New Music at the University of Huddersfield) is now available. This issue provides a range of technical and aesthetic perspectives on the creation and perception of contemporary spatial electroacoustic music. This issue was edited by Professor Eric Lyon (Virginia Tech).

My article with Dr. Brian Bridges (University of Ulster) examines a developing approach to the design of performance systems for spatial music.

Editor’s comments:

“Ricky Graham and Brian Bridges explore spatial performance practice with a focus on spatial mappings and gestural narratives. Their detailed report on technical implementations will be of particular interest to musicians working to extend the boundaries of spatial sound performance.”

Article abstract:

“This article will explore practical and aesthetic questions concerning spatial music performance by interrogating new developments within an emerging hyperinstrumental practice. The performance system is based on an electric guitar with individuated audio outputs per string and multichannel loudspeaker array. A series of spatial music mapping strategies will explore in-kind relationships between a formal melodic syntax model and an ecological flocking simulator, exploiting broader notions of embodiment underpinning the metaphorical basis for the experience and understanding of musical structure. The extension and refinement of this system has been based on a combination of practice-led and theoretical developments. The resulting mapping strategies will forge new gestural narratives between physical and figurative gestural planes, culminating in a responsive, bodily based, and immersive spatial music performance practice. The operation of the performance system is discussed in relation to supporting audiovisual materials.”

Link to Journal

Marco Donnarumma – Xth Sense at Stevens Tech – Oct 6th

The Xth Sense™ (2010-14) is a free and open biophysical technology. With it you can produce music with the sound of your body. The Xth Sense captures sounds from heart, blood and muscles and uses them to integrate the human body with a digital interactive system for sound and video production. In 2012, it was named the “world’s most innovative new musical instrument” and awarded the first prize in the Margaret Guthman New Musical Instrument Competition by the Georgia Tech Center for Music Technology (US). Today, the Xth Sense is used by a steadily growing community of creatives, ranging from performing artists and musicians, to researchers in physiotherapy and prosthetics, and universities and students in diverse fields.

//web: http://res.marcodonnarumma.com/projects/xth-sense
//contact: prof. graham – rgraham1@stevens.edu

//share: marco_poster

Live Show (Forthcoming): ShapeShifter Lab – May, 13th – (Brooklyn, NYC)

shapeshifter_may13th-01

I have an up-and-coming show with Jay Dickson at ShapeShifter Lab in Brooklyn, NYC on May 13th) –  $5 in.

Starts at 7pm. Details are here and below:

Act 1: Jeff Thompson – set length – approx. 40 minutes.

Instrumentation: Guitar / Amplifier

Jeff Thompson is an artist, musician, programmer, maker, and teacher based in New Jersey, USA.

https://soundcloud.com/jeffthompson

Act 2: Ricky Graham & Jay Dickson (N.Ireland) – set length – approx. 40 minutes.

Instrumentation: Guitar / Drum Kit

Jay Dickson  is a drummer/percussionist from Derry, Northern Ireland.
Ricky Graham (signalsundertests) is a guitarist and producer based in Hoboken, NJ, originally from Belfast, Northern Ireland.

The Northern Irish duo have been writing post-rock, metal, and experimental music together since 2006.

https://soundcloud.com/jaydickson
http://soundcloud.com/rickygraham

Act 3: Maria Chavez (Headliner) – set length – approx. 40 minutes.

Instrumentation: Turntables (DJ)

Born in Lima, Peru, Maria Chavez is mainly recognized in the art community as an improviser, sound artist and curator.

Her sound installations, visual objects and live turntable performances focus on the values of accidents and it’s unique, complicated possibilities with sound emitting machinery like the turntable.

Influenced by improvisation in contemporary art, her work expands outside of the sound world straddling different disciplines of interest. This year, Chavez wrote and illustrated her first book object entitled, Of Technique: Chance Procedures on Turntable. The book serves as a how-to manual for those interested in learning the abstract turntablism techniques that she developed with the turntable. “While the contents of the book serve a practical means, the book as a whole is intended to be an interactive art piece.”

http://www.mariachavez.org/

‘Golden Circle’ (McLachlan) – A piece for chamber ensemble and tape

Above: John McLachlan’s piece, “Golden Circle,” for chamber ensemble and tape (produced by yours truly). The piece was commissioned by Miso Music Portugal for the Sond’Ar-te Electric Ensemble, premiered at the Música viva 2011 Festival. The work was presented as part of  “Nova” at RTÉ lyric on March 11th, 2011.

More info: http://matchmaker.newaud.eu/works/golden-circle

Sounds & Schemas: Moving Music Metaphors

The following videos demonstrate another set of developmental mapping strategies for spatial music performance, which exploit bodily-based metaphors (see Johnson 2007). This set of examples present moving sound objects (individuated audio for each guitar string) moving from the front of the performance space to the rear. As each object is passed to an audio effects channel (applying delay & filtering processes) as they approach the central point of the array in an attempt to reify the notion of time passing by the listener. Objects that maintain a certain amplitude as they reach the rear of the array will cease to move, assuming a fixed spatial location behind the listener, becoming an object of prior experience. New note events will always enter at the front of the loudspeaker array.

the future is in front of me | the past is behind me