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Just before removing mathmatical feedback section

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Experimental_Music_Assignment_2/essay/U1265119-Experimental_Music-Assignment2-Essay.tex
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\usepackage{blindtext}
\setkomafont{disposition}{\normalfont\bfseries}
\graphicspath{
{./resources/},
}
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research has been carried out into methods for attenuating and controlling
this effect.~\parencite[p.1]{waterschoot2010fyafc} However, the volatile
and unpredictable nature of acoustic feedback has been used to great effect
in both popular and avant-garde music. Pioneering guitarists such as Jimi
Hendrix have used the loop created through placing an electric guitar
pickup close to it's amplifier to compliment virtuosic guitar solos in
pieces such as Foxy Lady~\citeyearpar{} This is taken one step further in
avante-garde works such as Steve Reich's Pendulum Music, where feedback
becomes the focus of the piece entirely. This is discussed further in
section~\ref{pendulum}
in both popular and avant-garde music.~\parencite[p.186]{holmes2012eaem}
Pioneering guitarists such as Jimi Hendrix have used the loop created
through placing an electric guitar pickup close to it's amplifier to
compliment virtuosic guitar solos in pieces such as Foxy
Lady~\citeyearpar{} This is taken one step further in avante-garde works
such as Steve Reich's Pendulum Music, where feedback becomes the focus of
the piece entirely. This is discussed further in section~\ref{pendulum}
\subsection{Electronic Feedback}
Electronic feedback takes the principal of recursively feeding an output
@@ -315,20 +314,21 @@
\item System parameters
\end{itemize}
\paragraph{System Input} As with most systems, an alteration to the input
of the system will result in the alteration of the output. This is
generally true of feedback systems as, for example, providing an electronic
feedback circuit with a louder input will most likely result in a louder
output. This relationship may not be linear and depends on the design of
the feedback system, which in turn determines the indeterministic nature of
these systems~\parencite[p.19-27]{weisert2010ioi}. However, it still
provides a method for control over the output of the system. This is
apparent in Mumma's Hornpipe~\citeyearpar{mumma2002lem} where the performer
must adapt the input to the system (in this case the sound produced by the
french horn) in reaction to the electronic sound produced by the
``cybersonic console''.
\paragraph{System Input}\mbox{}\\
As with most systems, an alteration to the input of the system will result
in the alteration of the output. This is generally true of feedback systems
as, for example, providing an electronic feedback circuit with a louder
input will most likely result in a louder output. This relationship may not
be linear and depends on the design of the feedback system, which in turn
determines the indeterministic nature of these
systems~\parencite[p.19-27]{weisert2010ioi}. However, it still provides a
method for control over the output of the system. This is apparent in
Mumma's Hornpipe~\citeyearpar{mumma2002lem} where the performer must adapt
the input to the system (in this case the sound produced by the french
horn) in reaction to the electronic sound produced by the ``cybersonic
console''.
\paragraph{System Parameters}
\paragraph{System Parameters}\mbox{}\\
As stated above, the design of the feedback system will determine it's
reponse to a given input. A common method for controlling the design of a
feedback system is through the implementation of variable nodes, for the
@@ -353,7 +353,8 @@
understood that feedback causes a shift in rhythmic content over time. The
exact rhythmic alteration is dependant on factors such as the feedback
system, input signal and it's relationship with the subsequent iterations
of itself.
of itself. This is explored extensively in David Tudor's Pulsers (see
section~\ref{tudor})
\subsection{Spectral Implications of Feedback}
As with rhythmic content, feedback has a complex effect on the spectral
@@ -406,11 +407,11 @@
This piece has a clear focus on process and was described as "the ultimate
process piece" by Reich. Designed as an "audible scupture", the piece is
designed to limit interaction in order to focus on the natural interaction
of acoustic feedback. Control of aesthetics is determined by the
semi-indeterministic method of releasing the suspended microphones, then
allowing natural swinging motions to dictate sonic events and rhythms. This
process is described as semi indeterministic, as it is clear that the
designed to limit human interaction in order to focus on the natural
interaction of acoustic feedback. Control of aesthetics is determined by
the semi-indeterministic method of releasing the suspended microphones,
then allowing natural swinging motions to dictate sonic events and rhythms.
This process is described as semi indeterministic, as it is clear that the
microphones will swing back and fourth at diminishing amounts over time,
however the audible feedback, interplay between audible events, feedback
tone etc\ldots are largely left to chance. This created a stark contrast
@@ -418,24 +419,78 @@
uncontrolled feedback~\parencite[p.186]{holmes2012eaem}.
\subsubsection{Robert Ashley's The Wolfman~\citeyearpar{ashley2003w}}\label{wolfman}
- ref: kyle gann - robert ashley
\subsubsection{Robert Ashley's The Wolfman~\citeyearpar{ashley2003w}}\label{wolfman}
The Wolfman explores a number of aspects of acoustic feedback through the
use of vocalisms for the control of tape sample modulated feedback. By
creating even small vocal sounds, the performer is able to control the
aesthetics of the feedback loop demonstrating the exponentially complex
impact of even the simplest inputs to a feedback system, as described
previously. Ashley commented that "the vocal sounds used to induce the
feedback have to be extremely soft so as not to block it" and he regretted
that the piece was believed to be generated by screams, which was far from
true~\parencite[p.37]{gann2012ra}. The result is a massive build up of
distortion and noise that develops as more vocalisms are supplied to the
feedback loop. It has also been observed that the piece's spectral content
is largely dictated by the room acoustics, tending towards a build up of
high pitched, shrill tones in smalled rooms. This shows the general focus
on the concept of process in experimental
compositions~\parencite[p.18]{cage2011silence} as the piece may differ
dramatically based on the conditions of the performance.
\subsection{Electronic Feedback}\label{ElecFeed}
\subsubsection{David Tutor's Untitled~\citeyearpar{tudor1996twfle}, Toneburst~\citeyearpar{tudor2004lem}, and Pulsers~\citeyearpar{tudor1996twfle}}
\subsubsection{David Tutor's Untitled~\citeyearpar{tudor1996twfle} and Pulsers~\citeyearpar{tudor1996twfle}}\label{tudor}
Tudor's Three Works for Live Electronics aimed to explore the creative
possibilities of using live electronics for composition. This was achieved
by creating custom electronic circuitry for the generation, manipulation
and feedback of audio. This was then controlled through the live filtering
and amplification of the feedback circuits to alter the output over
time~\parencite[p.187]{holmes2012eaem}.\\
\paragraph{Pulsers}\mbox{}\\
Pulsers aimed to explore the temporal and rhythmic effect of feedback and
live elctronics by using extensive electronic feedback/amplification
networks to modify the sound of various materials such as a tape recording
of an electronic violin~\parencite{tudor1984twle}. By altering the amplification and filtering of the
circuit live, the performer is given control over the rhythmic aspects of
the output. This results in the controlled use of the complex rhythms
possible with feedback.\\
\paragraph{Untitled}\mbox{}\\
Untitled was created as an exploration of the use of "no-input" live
electrnics. The electronic setup consisted of a complicated feedback setup
designed to manipulate the characteristics of sounds created purely through
the electronics (without any external input from microphones or
recordings).
The live ajustment of electronic parameters created an interesting
improvisational element in Untitled, as the complex nature of the
circuitry created an interplay between performer and the system. The
performer would ajust parameters, the system would respond, and subsequent
alterations would be made as a result~\parencite{tudor1984twle}.
However, the tendancy for feedback to become uncontrollable and the
extermely complex signal path resulted in a piece too complex to be
manageable in terms of live performance. This is a good example of the
indeterminate, complex nature of
feedback.~\parencite[p.83-85]{weisert2010ioi}
\subsubsection{Gordon Mumma's Hornpipe~\citeyearpar{mumma2002lem}}\label{hornpipe}
A combination of electronic and person process due to the sound produced by
the electronic circuitry's interplay with the human improvisation in
reaction to create the final result.
Indeterministic due to the relative unpredictability of the electronic
circuitry.
Hornpipe is a composition that combines the input from a french horn with
custom electronic circuitry created by Mumma, in order to transform the input by
monitoring and altering output based on input resonance.
The piece aims to explore electronic circuitry as a form of extension to
the horn, as electronic characteristics are dependant on the input from the
horn and the acoustic space in which the piece is
performed.~\parencite[p.101-103]{nyman1999em}
This piece demonstrates a combination of electronic and human process as
the sound produced by the electronic circuitry's interplay with the human
improvisation in reaction creates the final result.
The piece also explored the indeterministic aspects of feedback due to the
unpredictability of the electronic circuitry based on the number of factors
that determine it's output.
\subsection{Amplification}\label{amp}
\subsubsection{John Cage's Cartridge Music~\citeyearpar{cage2013cm}}
\subsubsection{Stockhausen's Mikrophonie~\citeyearpar{stockhausen1995mmt}}
\section{Conclusion}
\printbibliography