Chapter 3: COMPUTER
MANIPULATIONS OF A DIGITIZED AUDIO PERFORMANCE OF A POETRY READING.
Aspects of text reading
and music performance
Electro-acoustic
examples of speech manipulation
Altered voice: I am
sitting in a room
Enhanced voice:
Smalltalk and Late August
Composition of the
piece Someone
The computer and
composition processes used in Someone
The algorithms used
for Someone and their functions
Speed of the different
glissandi used in Part One
Construction of the
Nine Parts
Chapter 3
COMPUTER
MANIPULATIONS OF A DIGITIZED AUDIO PERFORMANCE OF A POETRY READING
This chapter looks at the
process taken in deriving a musical composition from a poetry reading. To this
end a recording of a reading of the poem Saint Dymphna's Bells by its
author Barry Dickins, is manipulated using algorithms built with the IRCAM
Signal Processing Workstation (ISPW) to produce the musical work Someone
(compact discs Three, Four, Five, Six and Seven). The whole poem and a ten
second segment from the beginning of the poem are repeated and adjusted in
several ways to produce an installation of indeterminate duration.
The installation is made up of
nine separate parts of different durations and incorporating different ways of
using similar techniques; the parts and the techniques used to produce them are
discussed below in the section titled: The composition processes used in Someone.
Aspects of text reading and music performance
In
the paper Music and speech performance: Parallels and contrasts. Rolf
Carlson, and others, put forward that:
in speech many different
prosodic factors are mixed together as one single acoustic parameter. [For
example] segmental inherent pitch, word tone, sentence type, lexical stress,
emphasis etc. can all be signalled in one single parameter, such as the voice
fundamental frequency. In the same way, the duration of speech sounds is
affected by a variety of conditions including stress, position in the
utterance, and local phonetic context.
The
same applies to music. There are many different reasons to lengthen or shorten
a note beyond its nominal duration [For example] emphasis, marking of phrase
endings, and sharpening the contrast between categories[1].
Lengthening or shortening note
durations are just one of the many tools available to musicians when
interpreting music. Other tools include varying the pitch, amplitude and/or
timbre of a note or phrase. These tools serve to allow each musician to imbue a
composition with their own expressiveness.
The degree to which a musician
can interpret a composition is dependent on the idiom in which he or she is
playing. For example: jazz musicians are expected to be able to interpret and
extemporise on a pre-existing melody within the jazz idiom and in order to
maintain idiomatic correctness. The degree of variations that can be made and
the palette of variations available in this idiom are quite broad, depending on
the idiomatic subset of the jazz idiom they are playing in.
On the other hand,
non-improvising musicians, such as classical orchestral musicians and classical
music soloists, are expected to interpret with a smaller palette. Here the art
of interpretation is far more critical. A musician whose role is as part of an
orchestra is expected to subject their own interpretation of a composition to
that of the conductor, who in turn is subject to the composer's act of
self-expression, that is, the composition.
Table 3.1 lists some of the
variables that are available to musicians and speakers in adding a degree of
self-expression when performing a text or composition. Under each heading three
possible variables are listed; there are, of course, other options available to
the performing speaker or musician.
Table
3.1 Variables in music and speech performance and composition.
|
Possible
Speech Variables |
Possible
Musical Variables |
|
3.1.1
Amplitude variation a)
varying the emphasis placed on certain syllables within a word or phrase; b)
wholly increasing or decreasing the amplitude of a word or phrase; c)
varying the amplitude within a syllable. |
Amplitude
variation a)
varying the emphasis placed on certain notes within a section or phrase; b)
wholly increasing or decreasing the amplitude of a note or phrase; c)
varying the amplitude within a note. |
|
3.1.2
Pitch variation a)
varying the pitch of certain syllables within a word or phrase; b)
wholly raising or lowering the pitch of a word or phrase; c)
varying the pitch within a syllable. |
Pitch
variation a)
varying the pitch of certain notes within a section or phrase; b)
wholly raising or lowering the pitch of a section or phrase; c)
varying the pitch within a note. |
|
3.1.3
Rhythmic variation a)
varying the inter-onset time between certain syllables within a word or
phrase; b)
wholly increasing or decreasing the duration of a word or phrase; c)
varying the inter-onset times or durations of syllables. |
Rhythmic
variation a)
varying the inter-onset time between certain notes within a section or
phrase; b)
wholly increasing or decreasing the duration of a note, section or phrase; c)
varying the inter-onset times or durations of notes. |
|
3.1.4
Timbre variation a)
varying the timbre of certain syllables within a word, or words within a
phrase; b)
wholly changing the timbre of a word or phrase; c)
varying the timbre of a syllable. |
Timbre
variation a)
varying the timbre of certain notes within a section or phrase; b)
wholly changing the timbre of a note or phrase; c)
varying the timbre of a note. |
|
3.1.5
Lexical variation varying
certain words or certain syllables within a word or phrase; |
Melodic
variation varying
the role of certain notes within a section or phrase; |
For the most part these
variations are generated intuitively by the performer. The performer's
intuitions are rooted in cultural knowledge of the effect of intonation on the
listener. This is well observed when listening to Eberhard Blum's performance
of John Cage's Sixty-two mesostics re Merce Cunningham.[2]
Here the text reading is manipulated in all of the ways given in Table 3.1 and
more. Blum uses the text as a vehicle for a wide variety of vocal expressions.
Phones, syllables and larger groups of vocal sounds are stretched, bent,
constricted and, in general, distorted from their normal use in the English
language so as to become a hybrid language existing somewhere between music and
English.
Electro-acoustic examples of
speech manipulation
The manipulation of vocal sounds
via electronic media has been happening since recording technology became
available. Early practitioners, such as Henri Chopin, used the analogue audio
tape domain with striking results. As digital electronics became available the
palette became broader and composers were able to enhance and alter the vocal,
speech or textual input in a wider variety of ways. This can be seen in the
more contemporary works of Paul Lansky and Roger Reynolds, among others.
The use of speech in
electro-acoustic composition can be divided into three categories: direct
voice, altered voice and enhanced voice. I have used the works of three
composers which exemplify each of these categories. The discussion of the
pieces below serves to give a background to my approach to using voice and is
not intended as a proper or definitive analysis of the pieces. The pieces discussed
here are: Come out[3],
by Steve Reich; I am sitting in a room[4],
by Alvin Lucier; and Smalltalk and Late August,[5]
by Paul Lansky.
In each of these pieces the
composer creates an environment, through electro-acoustic media, in which the
text mutates without too much guidance from the composer, with the possible
exception of Smalltalk and Late August. By reducing the input of
the composer during the composition of the piece the changes that occur are
created by either the text or the environment used in the recording. This means
that what the listener hears is not so much driven by the taste of the composer
as by the text itself.
These works are precedents to
the pieces presented here and exemplify the processes of electro-acoustic
composition used for my dissertation. For each piece I list important changes
as they occur in the form of a timeline.
Direct voice: Come Out
Steve Reich's Come Out
uses an analogue tape recording of a man saying the sentence "I had to let
the bruise blood come out to show them". His technique is to overlay
repetitions of the words "come out to show them" in such a way that
the layers move in and out of phase with themselves. This results in shifting
rhythmic patterns which draw the listener's attention away from the lexical
meaning of the words and towards the interplay of sonic patterns found within
the words. Reich describes the piece thus:
The phrase 'come out to show them' was recorded on both
channels, first in unison then channel 2 slowly beginning to move ahead. As the
phase begins to shift, a gradually increasing reverberation is heard which
slowly passes into a sort of canon or round. Eventually the two voices divide
into four and then eight[6].
The
main structural and driving element of the piece is the rhythmic counterpoint
between the voices. As this counterpoint progresses, through the perceived
adding of more iterations, the text is increasingly obscured until it becomes
unintelligible as text. Figure 3.1 is a rough melodic and rhythmic
transcription of the rhythm and contour of the main motif, "Come out to
show them".
Figure 3.1
Melodic structure of Come out.
This rhythmic motif fits very comfortably
into use as a hocket, which could be the main reason for Reich's use of it.
As the piece progresses the
three distinct sections become apparent, as Reich describes. In the first
section we hear the voice gradually gain spatial depth through perceived, not
actual, reverberation, then lose it's textual characteristics for musical
characteristics as repetitions of the voice increase, or "divide",
this "division" is the most important compositional process used in Come
Out. The entire acoustic signal used for Come Out is made up of
simply one, two, four or eight iterations of the phrase "Come out to show
them". These iterations operate as a very finely displaced hocket creating
illusions of traditional signal processing devices even though signal processing
plays no part in the composition.
Apart from choosing the sound
source, setting up the tape machines and then switching them on, Reich's only
other compositional input to Come Out was to decide when the piece
should "gradually [pass] into a canon or round for two voices, then four
voices, and finally eight"[7].
When listening to one side of
the stereo recording the doubling of the voice from one to two to four and
finally eight is striking, but is obscured when listening in stereo. Table 3.2
shows an approximate timeline of the perceived changes as Come Out
progresses; these changes are what the ear is drawn to over the duration of the
piece.
Table
3.2 Timeline of perceived changes in Come Out.
|
Time |
Perceived changes |
|
|
Single voice |
|
0" |
Complete phrase "I had to let the bruise blood
come out to show them" repeated 3 times; the phasing effect is not used. |
|
21" |
Two voices are now heard. |
|
21" |
"Come out to show
them" phrase begins and phasing effect begins. |
|
|
Slight shifts in stereo placement of the voice. |
|
|
Flanging slowly transferring into a delay; |
|
|
Depth is added through the phasing technique
simulating 'reverberation'. |
|
1' 45" |
Two voices appear, but their role as distinct
voices is not apparent. |
|
1' 50" |
"sh" sound becomes prominent. |
|
2' 0" |
The two voices become distinct as two voices. |
|
2' 19" |
The tempo and beat division of the phrase becomes
ambiguous, seeming to slightly slow down and speed up regularly. |
|
2' 59" |
Four voices are now heard. |
|
3' 0" |
Placement of voice moves in stereo field. |
|
3' 20" |
"Come out" and "show them"
become two distinct phrases. |
|
3' 55" |
The whole piece begins to be heard in a more
'reverberant' space. |
|
4' 30" |
Text becomes hard to distinguish, gradually losing
its meaning. |
|
4' 71" |
'Reverberation' becomes an important part of the
overall composition. |
|
5' 6" |
The text becomes less intelligible and more like a
musical sound source. |
|
6' 0" |
Two similar rhythmic motifs appear: come-a-come
out and show-de-show them, forming the most obvious hocket. |
|
6' 57" |
The two motifs move in stereo space. |
|
7' 10" |
"sh" sound becomes prominent again. |
|
7' 20" |
The rhythmic motifs fracture. |
|
8' 0" |
Each phone has a rhythmic pattern of its own, the
piece uses repetition to build intensity and its hocket nature becomes less
of a driving force |
|
8' 37" |
Eight voices are now heard. |
|
8' 40" |
Each phone, particularly the voiced and vowel
phones of the text, glissandos downward. |
|
9' 10" |
The downward glissandi begin to sound more
scale-like. |
|
11' 0" |
The piece sounds more like a pulsing timbre than a
succession of musical events; the effect of the phasing has reached its peak
and a very gradual fade begins. |
|
12' 54" |
Piece ends. |
This descriptive, foreground
analysis of Come Out shows how Reich's process shows features associated
with more usual musical composition processes, namely the use of motivic and
phrase repetition and variation.
While there are the obvious
repetitions of the text, other aspects of the sonic palette are also repeated.
'Reverberation', or proximity to the listener, is the foreground feature at 3'
55", 4' 17"; the perception of different numbers of voices at 2'
0", 3' 20", 6' 0"; motion in stereo space at 21" and 6'
57"; the "sh" sound at 1' 50" and 7' 10".
According to Richard Boulanger
"an important aspect of Reich's Come Out is that the natural
declamation of the text is preserved yet the speech undergoes a unique and
significant transformation"[8].
By taking this approach Reich has maintained the integrity of the text and its
reading and in doing so produced music which has evolved out of speech.
Reich's use of the repetition of
a short phrase in Come Out is influential in composing the
installation Someone, which is presented here. In Come Out shifting
repetitions of a phrase eventually obscure the textual meaning of the phrase,
and mutate the phrase from language into music. This method of transformation
by repetition of a single phrase is used and extended in Someone. In Someone
there are many more iterations of the phrase and the phrase is repeated in many
different ways. Its speed, pitch, the number of phrases being repeated at the
same time and stereo placement, all vary greatly when compared to Come Out,
where there are only two iterations of the phrase being repeated, no pitch or
speed variations and the stereo placement of each phrase is panned to hard left
and to hard right.
Throughout Someone the
text is heard in part and, in some sections, in full. Each repetition is heard
in and out of phase with each other, just as the repetitions of the text are
heard in and then out of phase in Come Out. This process serves
to spread the text over the listening area both spatially and temporally:
segments are heard in one area and then repeated in another, or a series of
segments are heard concurrently, depending on the listener's position. Segments
may follow in the order of the text or be reordered so as to lose the intended
flow of the text. Segments may also play in close temporal proximity to each
other, creating an effect similar to that of Come Out depending
on the placement of the listener.
Altered voice: I am sitting in
a room
This piece is built on an
analogue tape recording of Alvin Lucier describing what he is doing and why.
The process Lucier used was:
to record his voice onto one tape player, play it back on
another tape player through a loudspeaker and record that rendition onto the
first tape player[9].
This
process was carried out nine times for the performance of I am sitting in a
room, as it is presented in Source: music of the avant garde. The
recording was done in Lucier's living room.
The purpose of Lucier's
composition is described in the composition itself. Lucier uses this
description as the underlying and driving element of the composition. It is
what he says into the first tape recorder, creating the seed of the
composition, and is given below.
I am sitting in a room different from the one you are in
now. I am recording the sound of my speaking voice and I am going to play it
back into the room again and again until the resonant frequencies of the room
reinforce themselves so that any semblance of my speech, with perhaps the
exception of rhythm, is destroyed. What you will hear, then, are the natural
resonant frequencies of the room articulated by speech. I regard this activity
not so much as a demonstration of a physical fact, but, more as a way to smooth
out any irregularities my speech might have[10].
As each further rendition is
heard the sense of the text disappears. The cascading effect of the resonances
causes first distinct pitches to be heard, which create motifs, and then
metamorphose into a musical composition. Table 3.3 below looks in more detail
at each section, taking each rendition of the text as a section. References to
pitches are approximate.
Table
3.3 Timeline of perceived changes in I am sitting in a room.
|
Rendition |
Perceived
changes |
|
|
Rendition
1 |
Normal
text reading is recorded. |
|
|
Rendition
2 |
Reverberation
of the room becomes apparent, also the mid-range frequencies of the voice are
accentuated. The sound of Lucier's sibilances are accentuated. |
|
|
Rendition
3 |
Room
reverberation increases creating an impression of distance; it is now a
distinctive part of the sound of the voice. A single pitch is now heard,
triggered by the voice, which creates a harmony for the reading. |
|
|
Rendition
4 |
The
background noise becomes a feature in the piece. The text is becoming obscured
but is intelligible. More pitches are heard, still obviously triggered by the
voice, which create a melodic motif, or "accompaniment", around the
voice. |
|
|
Rendition
5 |
Text
is barely intelligible; whatever remaining intelligibility there is may be a
result of previous exposure to the text. The intonational pitch changes of
the reading now more obviously affect the melodic pitch changes of the
"accompaniment". |
|
|
Rendition
6 |
The
background noise is now a prominent feature and appears to have a number of
distinct pitches, forming a non-tempered cluster around C# 5. (F# and C# seem
to be the most resonant pitches of the room). The "accompaniment"
is now the main feature of the piece; the text serves as part of the timbre
of the "notes" of the "accompaniment". |
|
|
From
this point on it becomes difficult to separate the sections one from the
other. Between sections six and seven there is a tape glitch or break which
defines the beginning of the new section. |
||
|
Rendition
7 |
The
background noise now has two distinct pitches which it glides between
regularly. The text is completely obscured but the rhythm of the reading
continues to drive the piece. Three distinct parts now run simultaneously:
the background noise, the "accompaniment" and now an adjunct to the
"accompaniment" follows it but seems to have a different motif. |
|
|
Rendition
8 and Rendition 9 |
From
here there is a general smoothing of the overall sound of the piece. The text
has degraded to the point of being unintelligible and it is now difficult to
hear even the intonational aspects, which are now obscured as the piece takes
on all the aspects of music and loses all aspects of speech. |
|
Alvin Lucier uses repetition as
the main structural element in I am sitting in a room. He uses the many
and changing resonances that are produced within a room by the intonational
aspects of his text reading to create music from speech. This transformation of
speech into music using resonance is reflected in Someone. Here forty
artificial rooms have been created for the whole text and text segment to
resonate in. As in I am sitting in a room the pitch and duration of each
resonance is affected by the intonational aspects of the reading, creating
melodies and harmonies which transform the text reading into a musical piece.
In Someone and I am sitting in a room the resonances that we hear
created by the voice are amplified through repetition.
The difference in Someone
is in the characteristics of the artificial rooms. The dimensions of each room
change as the intonational aspects (rhythm, timbre, pitch and amplitude) of the
reading change, thus changing the qualities of each resonance and its effect on
the reading. By doing this the reading becomes the only causal aspect in the
piece. In I am sitting in a room the reading and the room have equal
roles in creating the piece; in Someone the reading has become the only
agent in creating the piece.
I am sitting in a room
influences Someone in two ways. First in the use of repetition of a long
phrase: in the case of Someone the whole poem is repeated; and second,
by using the intonational aspects of that text reading as the trigger to alter
the sound of both the whole poem and the segment of the poem. This process is
discussed later in chapter three under the heading "The computer and
composition processes used inSomeone."
Enhanced voice: Smalltalk
and Late August
Paul
Lansky's Smalltalk and Late August also alter the voice to
become unintelligible in a lexical sense. According to Lansky
Conversation [has the] ability
to change its nature when one no longer concentrates on the meaning of the
words. [What is heard is the] intonations, rhythms and contours of the speech.[11]
Smalltalk
is based on a recording of a domestic conversation between Lansky and his
wife, Hannah MacKay. The recording was treated on a DEC Micro Vax II running
software Lansky wrote for the project. This resulted in obscuring "the
words we spoke while capturing the rhythms, pitches and contours of our
conversation"[12].
Late
August resulted from Lansky wondering
what would happen if I tried the
same sort of thing with another language, say Chinese, in which pitch and
contour have different meanings. [The result] is similar to Smalltalk on
the surface, but quite different in substance the sound world of the Chinese
language led to a very different kind of music[13].
While
the music may be of a different substance and kind this surface similarity can
make distinguishing the two pieces difficult, especially in the first few times
they are listened to. This may be due to Lansky's use of conversational rather
than highly structured and stylised text, such as a poem. His desire to create
tonal centres that do not appear to be based in the pitch field of the voices
also obscures the difference between the substance of Smalltalk and Late
August.
Table
3.4 describes the perceived changes over time in both Smalltalk and Late
August. In this description of the changes over time in both pieces it is
not essential that any of the textual foreground be mentioned. This aspect of
the pieces is subject to and obscured by the effects that Lansky applies to it.
To include a more detailed description of the foreground melody or harmonic
changes would also obscure the description of Lansky's large scale structural
composition of the pieces.
Table
3.4 Timeline comparing perceived changes in Smalltalk and Late
August.
|
Smalltalk |
Late August |
||
|
Time |
Perceived changes |
Time |
Perceived changes |
|
0'0" |
Melodic foreground and middle tessitura. |
0'0" |
Melodic foreground with high, wide tessitura. The
accompaniment is based on aspirant-like sounds. |
|
38" |
Faint single note accompaniment background. This
accompaniment is based on back vowel-like sounds[14]. |
|
|
|
1'13" |
Accompaniment background becomes lower in pitch. |
|
|
|
1'22" |
Return to original accompaniment pitch. |
|
|
|
1'35" |
Accompaniment becomes more dense. |
|
|
|
1'45" |
Accompaniment background an octave lower. |
|
|
|
2'07" |
Complete change in background, moves to a different
scale/key. |
|
|
|
2'35" |
Background accompaniment increases in activity. |
|
|
|
|
|
|
|
|
|
|
3'02" |
Large change in accompaniment. |
|
3'29" |
Return to original background accompaniment harmony/scale. |
|
|
|
3'54" |
Accompaniment shift. |
||