Felipe Otondo
Department of Music
University of York
York Y010 5DD United Kingdom
http://music.york.ac.uk/
fo500@york.ac.uk
Creating Sonic Spaces:
An Interview with
Natasha Barrett
Natasha Barrett is a freelance composer who cur-
rently lives in Norway. Her compositional output
consists of works for instruments and live electron-
circuitos integrados, sound installations, dance, theatre, and anima-
tion projects, but all her energy seems to stem from
her acousmatic composition. En 2006, she received
the Nordic Council Music Prize—the most presti-
gious recognition for a Nordic composer. She has
also received awards from the Bourges International
Electroacoustic Music Competition (1995, 1998,
2004), Concurso Internacional de Música Elec-
troacústica de São Paulo (2001), the International
Rostrum for Electroacoustic Music (2002), y el
Noroit Electroacoustic Music Competition in France
(1998, 2002), among others. Barrett’s projects are fre-
quently commissioned by international organiza-
ciones, and her music is available on the Empreintes
DIGITALes, Cultures electroniques/Mnemosyne
Musique Media, Centaur, Computer Music Journal
Antología sonora, Prix Noroit, and Aurora labels.
Her studies include a master’s degree at Birm-
ingham University with Jonty Harrison and a doc-
toral degree supervised by Denis Smalley at City
Universidad, Londres. Mesa 1 provides a list of her
compositions.
This interview took place at the International
Computer Music Conference in Barcelona, España,
en 8 Septiembre 2005, and was focused primarily on
the composer’s thoughts on spatialization. Desde
this interview took place, the transcription has been
augmented with additional information in subse-
quent communication with Ms. Barrett.
The Listening Space
Felipe Otondo: You have been dealing with spatial
design for quite some time. What is your approach
toward the use of space in electroacoustic music?
Computer Music Journal, 31:2, páginas. 10–19, Verano 2007
© 2007 Instituto de Tecnología de Massachusetts.
Natasha Barrett: It depends on your listening
espacio. If for now you think about space away from
the context of the listener—for example, if you are
alone in the studio—I think you can compose a
three-dimensional impression of space, even when
you manipulate phantom images with two loud-
speakers. In stereo, you can then create a great
deal of depth—you can work with many degrees
of middle-, fore-, and background. This sense of
space is often captured through a careful recording
técnica. Pero entonces, por supuesto, as soon as you
leave that private listening space, your composed
space may collapse because you are no longer in
control of your environment. En este punto, I find
that spatial information suggesting simple room
acoustics can be quite stable, whereas other types
of spatial information that create, Por ejemplo, a
sense of perspective, occupation, or embodiment,
are fragile.
So then you need to think, “How is my space go-
ing to function?”—and you might like to try alter-
native spatialization techniques. Además, tú
need to decide whether you are aiming at home or
concert listeners, in which case I think you need to
approach these situations in different ways. Uno
way in which I have found common ground for con-
cert and home listening has been with surround and
ambisonics spatialization.
Otondo: Don’t you see a contradiction there—a
problem that many people don’t seem to be aware
of—a conflict between this space you can create in
the studio and this open space in a concert?
Barrett: Well, as soon as you take your stereo work
into a concert, you can make it sound multichannel
and occupy the room. I expect other people you
have interviewed have said the same thing. A menudo,
when I talk to someone outside our field, they ask
how many channels I have in the source. They don’t
believe me when I say it is stereo. If the loudspeak-
ers are set up correctly, if you have the right space
and you know what you are doing, then you can
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Mesa 1. Compositions by Natasha Barrett
Título
Crack Process
Instrumentation/Medium
Percussion, trumpet, electric guitar, and computer
(ambisonics and conventional multichannel)
Año
2006
Deep Sea Creatures
Acousmatic (stereo, 5.1, 12-ch, or 16-ch) (ambisonics
2006
Mobilis in Mobili
Trade Winds
and conventional multichannel)
Acousmatic (stereo, 5.1, 12-ch, or 16-ch) (ambisonics
2006
and conventional multichannel)
Acousmatic (stereo, 5.1, 12-ch, or 16-ch) (ambisonics
2006
and conventional multichannel)
Hommage à Parmerud
Abemolpas (Avoid being eaten by mimicking Acousmatic (5.1, ambisonics, and conventional
Acousmatic (stereo and 5.1)
other less palatable species)
Where shadows pass for bodies stand
Exploratio Invisibilis
Symbiosis
Prince Prospero’s Party
Angels & Devils
. . . fetters of a dream . . . (Fetters)
Agora
Push-me-Pull-me
Industrial Revelations
Displaced : Replaced
Rain Forest Cycle
RAS
Utility of Space
Liquid Crystal
Three Fictions
Circadian Cycles
Viva la Selva!
Diabolus
Outspan
Mimetic Dynamics
Microclimate II: Red Snow
Microclimate I: Snow & Instability
Buoyant Charm
Little Animals
Surf
St Paul’s Descending into the
Autumn mist
Racing Unseen
Racing Through, Racing Unseen
Earth Haze
Swaying to See
Imago
Puzzle Wood
multichannel)
Classical guitar and computer (stereo)
Acousmatic (ambisonics and stereo)
Cello and computer (stereo)
Acousmatic (ambisonics and stereo)
Acousmatic (stereo)
Acousmatic (stereo and 5.1)
Electroacoustic Theatre (16-ch acousmatic,
sound-making installation, and soprano)
Cello, violin and computer (stereo)
Acousmatic (stereo)
Installation (ambisonics cubic array)
Installation (triangular pyramid array)
Percussion quartet and computer (stereo)
Acousmatic (ambisonics and stereo)
Clarinet and computer (stereo and multichannel)
Acousmatic (stereo)
Sinfonietta and computer (stereo and multichannel)
Acousmatic (stereo)
Percussion, voice, computer (stereo)
Acousmatic (stereo)
Installation (quadraphonic)
Acousmatic (stereo)
Double bass, alto flute, percussion, and computer (stereo)
Acousmatic (stereo)
Acousmatic (stereo)
For two classical guitars and computer (stereo)
Acousmatic (stereo)
Acousmatic (stereo)
Acousmatic (stereo)
Acousmatic (stereo)
Acousmatic (stereo)
Clarinets and computer (stereo)
Acousmatic (stereo)
2005
2004
2004
2003
2002
2002
2002
2002
2002
2001
2001
2000
2000
2000
2000
2000
2000
1999
1999
1999
1999
1999
1998
1998
1997/2001
1997
1997
1997
1996
1996
1995
1995
1995
1994
Otondo
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make a good diffusion performance sound ex-
tremely multichannel and multilayered.
Otondo: You are good at diffusion performance.
Barrett: I started in Birmingham during a master’s
degree supervised by Jonty Harrison and have been
practicing ever since. I can play okay—I enjoy it and
I know that I can project the right thing in the music.
Otondo: But it was not enough for you? Why did you
feel you needed more?
Barrett: There are some limits to sound diffusion in
the concert. Yet there are also some advantages.
Sound diffusion is a performance practice involving
interpretación, and you can tailor the spatialization
to work within the space of the concert hall. Alguno
compositions demand a specific diffusion perfor-
mance for the musical structure to be clear. Otro
music gives the performer a greater degree of inter-
pretation. But whatever the intentions from the
compositional side, you cannot project the simulta-
neous spatialization of different sound streams, hacer
things that are impossible to do with one pair of
manos, work with the idea of spatialization as a
structuring method reliant on details a performer
may miss, Etcétera.
The last point is maybe most important for me.
If the diffusion interpretation does not convey the
composed spatial intentions, then you could say that
the spatial musical structure becomes a bit less accu-
rate and takes a direction other than that intended.
No es sorprendente, I have experienced this scenario
mostly at events where diffusion as a performance
practice is a rarity, even though the performer may
have an understanding of the music. Sin embargo, con
ambisonics, because you can accurately compose the
spatial information, you gain tighter control over
the spatial musical structure and therefore allow it
to play a more important role. With sound diffusion
actuación, you really have to accept some chance.
Otondo: And then the performer plays a big part in
él, giving a unique interpretation of the piece with
whatever style or assumption is desired.
Barrett: Exactly, and this performance can make a
“not-so-good” piece sound fantastic, but it can de-
stroy a great piece if it goes against the spatial musi-
cal structure present in the music. So when you
want to go further than spatial generalizations—if
you want to work with spatial hierarchy where tiny
movements in space and spatial relationships con-
tribute to sound identity—you need a technique
that is not going to break in performance. Esto es
the point where I started to move into ambisonics.
Ambisonics can also result in a concert disaster, pero
that is a technical rather than a performance inter-
pretation issue. Tiene, sin embargo, meant that since
my sudden burst of ambisonics compositions in
2000–2003, I am now more selective when I choose
to use the technique.
Otondo: Can you explain a little more about
ambisonics?
Barrett: I’ll try to give an easy introduction. En el
moment there are two main ways to create and ma-
nipulate a virtual three-dimensional sound field, o
a sound field that mimics the properties of our real
acoustic sound field: ambisonics and wavefield syn-
tesis. Each involves quite different methods, pero en
a perfect world would produce the same result. A
capture or encode the spatial information in the
first place, we have two choices: either we can at-
tempt to capture the real sound field via recording,
such as by using a Soundfield microphone, or we
can synthesize the spatial information using the
math of either ambisonics or wavefield synthesis.
With ambisonics, higher-order representations pres-
ent a more accurate description, where each order
corresponds to an order of spherical harmonics.
Otondo: Can you explain a little more about the
higher-order representations?
Barrett: You can make a comparison to spectral rep-
resentimiento, where if you try to represent a complex
sound with one sine tone you don’t get very far. Pero
the more harmonics you add, the closer your repre-
sentation will be to the original. The same goes for
capturing the three-dimensionality of sound using
spherical harmonics. The Soundfield microphone
can capture a first-order representation, de lo contrario
known as B-format. This is not a very accurate de-
scription of the sound field compared to higher-
order representations. Therefore I choose to work
more with the latter.
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Cifra 1. Natasha Barrett.
Creating Spaces
Otondo: Listening to your music, one gets the feel-
ing that you are quite concerned with the issue of
creating spaces. You are very good at making the lis-
tener perceive both tiny and large spaces; sometimes
with small objects you can create a huge space. Es
this related to the idea of allusion that you wrote
about in articles (Barrett 1999, 2002), working with
the material as a way to create space?
Barrett: Creating spaces is strongly connected to
the experience of our surroundings, and in this re-
spect, spatial mimicry made possible with ambi-
sonics can be a useful approach. But you are correct,
it is also very much connected with the idea of allu-
sión. When you consider very tiny sounds building
up an impression of space, then you can begin to
imply a space within which these sounds should
live. If you use abstract sound material, it can be dif-
ficult for the listener to find the spatial context. Si
you don’t want to use reverberation, you don’t have
a clear spatial context to start off with, either. Pero
gradually, as the sound material unfolds, its behav-
ior, its motion behavior—the relation between
many things happening at once—imply space, incluso
though you are not using reverberation or clear
sound identities. This is something I find very inter-
esting because I don’t like using reverb. When I do, I
try to calculate a realistic room model using ambi-
sonics reflections.
Otondo: How does that work?
Barrett: I calculate the early reflections as ambi-
sonics reflections in the virtual space. Pero, as I said,
I try not to use reverberation. I prefer to use convo-
lution in a way that doesn’t explicitly say “this is a
small room” or “this is a big room.” I find normal
reverberation distracts too much from something
else you might be trying to do.
Otondo: Has this to do with the idea of putting a
room inside another room as Dennis Smalley
(austin 2000) suggests?
Barrett: That’s one part of it, the problem of com-
bining the listener’s space with the space in the mu-
sic. But I think it also has to do with the fact that a
Otondo
13
Otondo: So once you have captured or encoded the
spatial information, what next?
Barrett: Then we need to reproduce, or decode, el
soundfield information over our chosen speaker
arrangements. It is here that more compromise is
needed. The higher the order of the encoding, el
more loudspeakers we need in the decoding. But a
nice compromise is to use a third-order encoding,
which in the horizontal axis requires a minimum of
eight loudspeakers and fits quite nicely into a small
concert situation.
Working practically with compromise is the nice
thing about ambisonics over wavefield synthesis.
For wavefield synthesis to recreate a soundfield,
little compromise is possible, and large numbers of
adjacent loudspeakers are required. Other compro-
mises involve considering our perceptual interpreta-
ción. How much accuracy of spatial information is
perceptually relevant? How can we treat the sound
material to enhance the perception of spatial cues
through filtering, loudness, and pitch changes? En
many situations I begin with stereo sources and
then relocate the sound image within my composed
ambisonics soundfield. This sometimes involves
splitting the sound into different frequency layers,
each located in a slightly different spatial position.
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clear reverberation effect can dominate what you
are doing. It blurs spectral detail and “messes up”
textural information. It can distract the ear from
something more important, such as the indirect im-
plication of space. Para mí, it is at that moment of
implication and ambiguity that music starts to
come through. The listeners start to use their imag-
ination and their own experience to find a place in
the music.
Ambisonics and the Hybrid Approach
Otondo: Going further into ambisonics, do you
think that aside from the advantages of three-
dimensional sound, these systems are still restric-
tive for most composers? They can be complex and
quite expensive . . . you need very specific studio
software and hardware.
Barrett: First of all, ambisonics is not expensive,
y, for the user, it is not technically challenging.
Provided you don’t want to program the math, es
not technically challenging at all. The software I
use is free, and there are in fact quite a few com-
puter music centers working with ambisonics, pero
maybe not so many full-time composers. Hay,
sin embargo, problems with the stability of the ambi-
sonics sound field that I touched on. Because ambi-
sonics is an encoding and decoding system where
you encode the spatial information and decode the
result for the locations of your loudspeakers, este
means that if you decode in advance, you have to
place your speakers in the exact locations for which
you decoded. Unless the hall is completely flat and
of correct geometry, it is very difficult to place the
loudspeakers correctly.
Ahora, with ambisonics, the nice thing is that you
can decode your encoded information for (theoreti-
cally) any loudspeaker geometry, and so you might
think it would be easy to decode on site. But in
práctica, that doesn’t always work, because the de-
coding algorithms currently do not cope well with
asymmetry in loudspeaker placements and loud-
speaker responses. So as soon as you change a circle
to an oval—just that compression along one axis—
the decoding algorithms will not work as well.
Otondo: What happens then?
Barrett: When loudspeakers are different distances
from the central point, you have to think about phase
problems throughout the spectrum and volume dif-
ferences. The sound field will be distorted and will
break down. En la práctica, when listening, this can re-
sult in an uneven sound distribution, front–back re-
versalles, or simply a feeling of spatial mono or spatial
“meaninglessness.” In my successful ambisonics
concerts, I’ve carefully set up the loudspeakers just
for this music. Sin embargo, if you setup a diffusion rig
in the standard European diffusion format, como
the BEAST format (harrison 1998), stereo diffusion
will work much better than ambisonics. Actualmente, I
normally only set up an ambisonics concert array if
I am playing only ambisonics works, or if the project
is an installation where I can exactly locate the equip-
mento. Despite my faith in soundfield recreation tech-
niques, I also need to be realistic about my demands!
Otondo: But it does fit well with 5.1 surround?
Barrett: Sí. Even though 5.1 is asymmetric, el
loudspeakers are the same distance from the center
punto, which makes decoding easier than, Por ejemplo,
for an oval. When composing for a fixed speaker array
como 5.1, I sometimes use normal panning as well.
One of the great things about ambisonics is that it is
easy to make a feeling of space and to make clear tra-
yectorias. But when a sound is stationary, then the
location is not quite as clear, and it is better to place
the sound in a conventional way. Straightforward
5.1 for home listening is not a problem, but I don’t
think 5.1 works that well in the concert where the
listener is not sitting in the perfect location. en contra-
certs where it has been necessary to play from a 5.1
source, I have used at least two 5.0 configurations—
uno 5.0 configuration close and one distant or one
elevated, and manually diffused between the two
with careful control over the subwoofer channel.
Otondo: So you create the piece in ambisonics and
then you do the mix again in 5.1?
Barrett: De hecho, I first create the piece in quad or
stereo while listening in the perfect position. Con
my first ambisonics piece (The Utility of Space), I
worked in a second-order, nine-channel ambisonics
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Cifra 2. Dodecahedron
setup from the ambisonics
version of Exploratio
Invisibilis.
format from the beginning, and my computer was
not fast enough to do all the multichannel mixing
and decoding in real time. I had to encode and then
decode out of real time and then mix and listen. Él
was a big piece that took too long sitting and wait-
ing for the computer to complete the task. Now ma-
chines are faster, and software has changed. Con
many of my ambisonics pieces, I spatialize maybe
20 simultaneous items, which still puts a strain on
the computer if also simulating air absorption, el
Doppler effect, and maybe a few early reflections.
Otondo: So, what do you do then?
Barrett: Then I use scripting software that allows
me to script as many simultaneous objects as I
want, but as a non-real-time process. Then we are
back to first working in stereo or quad, getting a
good sense of potentially three-dimensional infor-
formación, and—when all other aspects of the compo-
sition are correct—implementing spatial ideas that
I could only plan or imagine in the earlier stages.
You could say that I render the high-quality ver-
sion at the end once I’ve got the composition “right.”
To some people, it may sound strange that I compose
first in stereo or normal quad and then realize the
ambisonics version once the materials, the timing,
the counterpoint, and the flow are correct. Things
do change when you compose the ambisonics field,
obviously—when calculating Doppler shifts and fil-
tering, pitch and volume changes! Then you have to
go back and change the material—but to do most of
the composition first in the more traditional format
makes the complete process manageable.
Otondo: So you have developed a sort of hybrid
acercarse . . .
Barrett: Sí, I have from the compositional point of
vista, because the technical aspects of ambisonics
were starting to get in the way of the compositional
proceso.
Otondo: This allows you to work with more tradi-
tional spatial formats. I guess you spend some time
doing all this.
Barrett: Well, it’s quicker now because software is
easier to use and more accommodating to multi-
channel formats.
Otondo: How do you compensate in ambisonics for
the size and the acoustics of the hall?
Barrett: If it is a very reverberant space, you don’t use
ambisonics. In a large-room acoustic, the music needs
care to bring out the detail. In that case, I would go
for diffusion, and I would go for the diffusion of stereo
rather than multichannel. This is because you can con-
trol the piece better and adjust for the changes that hap-
pen due to the sound moving in a big acoustic with a
strange coloration. In a very reverberant room, the only
reason I would use a multichannel version is if the
piece were to be divided into layers that I would diffuse
simultaneously, and not as, Por ejemplo, eight fixed
canales. You could call it multiple-stereo diffusion.
Multichannel and 5.1 Surround
Otondo: Just about that, what is your opinion about
the conventional approach of multichannel diffusion?
Have you made pieces that are just multichannel?
Barrett: Not multichannel in a conventional sense.
My first multichannel piece was in fact an ambi-
sonics work (The Utility of Space), and was later
mixed to stereo for practical reasons.
Otondo
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Otondo: Do you think purely multichannel compo-
sition is restrictive?
Barrett: It depends how you work. Por ejemplo,
Barry Truax has worked in a way where his compo-
sitional approach is partly dependent on the multi-
channel setup (Truax 1999). So, it depends on the
kind of music and the approach that you have, y
my approach is not like that. It would therefore be
inappropriate for me to start that way.
Otondo: It is very difficult to monitor with eight
speakers in a conventional studio.
Barrett: That’s right, it is difficult. I think Annette
Vande Gorne has a studio where they monitor in
eight. I remember it’s very nice there. yo a veces
monitor in an octagonal setup, but only in the last
stages of the composition. If you are not working
with speakers as independent voices, then there is
less reason to monitor over eight speakers—at least
in the horizontal axis. As long as you are sitting in
the perfect position, four speakers are enough. En
that respect, I have composed directly into quad for
some parts of a piece, and then converted the mix to
eight channels or multiples thereof, or separate near
and far layers, and near and far multichannel mixes.
Otondo: Don’t you think one could combine both
multichannel techniques? Maybe surround 5.1 es un
good example of that.
Barrett: Por supuesto, you can combine any tech-
nique—there is no limit. It just depends on the mu-
sic and your intention. In a way, 5.1 surround is a
hybrid combining the idea of the center speaker as a
voice with normal phantom images.
Otondo: I have been working a bit with surround
5.1 trying to get an idea of the transition from the
living room or studio situation to the concert hall
situation, and I have found that it is a very complex
transition in terms of spatial experience for the lis-
tener (Otondo 2005). What is your approach towards
surround 5.1? Do you think it is something fashion-
able that will disappear in some time?
quad and drop the center channel or pan it center
frente. Pero, if I am thinking in a practical way, then I
have to understand that most people who buy a 5.1
setup are not audio experts—they have a home cin-
ema system. El 5.1 layout does not fit into all liv-
ing rooms, but it can, if you reorient furniture and
change your life a little bit! But to contradict my-
self, playing ambisonics goes “out the window”
cuando el 5.1 system consists of three unknown and
different types of loudspeakers.
Otondo: But what happens with 5.1 in the concert
hall?
Barrett: In the concert hall there are two problems
with 5.1—maybe more than two problems, pero dos
main problems. The first problem is that in a large
concert hall, the five speakers are far away from the
audience, so you loose a sense of intimacy. With dif-
fusion, por supuesto, you place speakers at different dis-
tances to the audience, whereas in concert playback
de 5.1, because the speakers are far away, the rever-
berant field blurs the direct source early on, y
there is nothing you can do about it.
The second problem has simply to do with five
speakers not being enough for a large space. Si usted
are not sitting in the center, then you get a biased
sound picture, and of course all the big cinemas use
more than just five loudspeakers. Often there will
be a large array at the front, and then extra loud-
speakers at the sides and back. This doesn’t solve
the loss of intimacy, but as large cinemas are rather
dry, reverberation does not cause so much of a prob-
lem. As I mentioned earlier, my own solution is to
work with multiple 5.0 configurations and diffuse
among them.
Otondo: So you also have this problem when you
go from ambisonics in a 5.1-channel arrangement in
the studio and you play it in a 5.1-channel system in
a concert hall?
Barrett: Same problems—interference from re-
verberation and not enough speakers to fill in the
espacio.
Barrett: No, I don’t think it will disappear at home,
because in a way it is a practical setup. Some home-
audio consumers don’t listen in 5.1—they listen in
Otondo: Let’s pretend I am a millionaire, and I will
give you the chance to play your music in a perfect
ambiente. What would you want?
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Barrett: Well, then I would tell you to build a con-
cert hall! Well, to be realistic, then I would say to
buy some good loudspeakers.
Otondo: How many speakers would you use then?
Barrett: Depends on the size of the space.
Otondo: A normal concert hall.
Barrett: A normal concert hall for ambisonics? Six-
teen would be good. Maybe another sixteen for ele-
vación. And then you could probably create a good
sound field. Pero de nuevo, you need to have the right
kind of speakers.
Otondo: Do you need the same type of speakers?
Barrett: For ambisonics, Sí. If not, different speaker
colorations and diffusion angles will distort the
recreation of the sound field.
Space and Composers
Otondo: Now I’d like to get into something more
general. Do you think there has been a change in
the approach toward space lately by electroacoustic
music composers due to cheaper and more sophis-
ticated equipment?
Barrett: [Laughs] Depends what country you are in.
Otondo: En general.
Barrett: Not as much change as there could have
estado. The main difference is that composers are us-
ing better reverberation effects. But the understand-
ing of spatial issues, at least among composers, es
still not so advanced.
Otondo: Don’t you think that cheaper sound cards
and the spatial possibilities of programs like Max/
MSP, pd, Spat, and others have opened new possibil-
ities for spatial design?
Barrett: Well, many people are working with multi-
channel music. The problem is that some appear
unclear as to why they are doing it. Maybe they work
with multichannel because it is “the thing to do.” I
tener, sin embargo, unfortunately been seated in bad lis-
tening positions in many multichannel concerts—
Cifra 3. Sound-making el-
ements from the installa-
tion part of Barrett’s work
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stuck on an end with one loudspeaker pointed at my
ear. I have experienced stereo diffusion that sounds
more “multichannel” than some real multichannel
pieces. One assumes that with multichannel you
can easily play with independent spatial trajectories,
but getting that to function in the concert space is
difficult once the music is fixed to maybe eight
canales. When the sound just gets stuck at the
back due to the room acoustics, speaker characteris-
tics, or inaccurate speaker placement, there is little
that can be done. In part I think the spatialization
equipment and technology have become readily
disponible, but the users haven’t caught up.
Otondo: Por qué? Because it is difficult?
Barrett: I would not say it is difficult, only that it
requires a level of understanding, as all skills do.
When you first begin, the temptation to swing
sounds around the room is enormous! It feels physi-
Otondo
17
cal and immediate. But spatialization is about so
much more than that.
Otondo: So new means imply new complexities,
but people are not really aware of it, they are just
using and abusing this technology?
Barrett: That is what I sometimes hear.
Instrumental Pieces
Otondo: I have listened to your piece Symbiosis for
cello and live electronics in one of the listening
rooms here at the ICMC and wanted to ask you,
what is the difference in the spatial approach when
you work with instruments compared to those
purely electroacoustic works that you mostly write?
Barrett: Well, I think my opinion is the traditional
uno. When a performer is on stage, the visual aspect
means you hear in a different way. And so in Sym-
biosis, you see the cellist on stage. She is not just
sitting there playing—she is moving around a little
bit and using her voice. It is a dynamic piece, y entonces
her whole physical presence is quite spectacular.
What you are seeing ties you down; it provides a
constant reference point regardless of whether the
sound is moving through the space. One has to take
advantage of this fact and not experience it as a
problema. Although the electroacoustic part of Sym-
biosis contains some spatially relevant non-cello
sound material, the cello is the center of that sound
world, and the performer is articulating the struc-
tura, visually emphasizing the aural totality. en par-
particular, sound propagates from the performer and
away throughout the space.
Otondo: So you take a completely different spatial
approach than with the purely electroacoustic
pieces—you try to understand things from a perfor-
mance perspective.
Barrett: The thing is that in reality, when you com-
pose a piece for a performer, normally the per-
former has commissioned the work and therefore
you should write something that is good to be per-
formed, something that takes full advantage of that
perfomer’s skills. Often you may have a musical
agenda that is not the same as the performer’s
agenda, especially coming from an acousmatic point
of view, and you need to balance these agendas and
find things that work.
Otondo: You have different goals you want to
achieve with the piece?
Barrett: A veces. Por ejemplo, unless I am com-
posing a purely theatrical work, my initial agenda is
sound, whereas the performers’ primary agenda is
actuación, and they are not necessarily the same
thing. Esto es, por supuesto, not always the case, but ei-
ther way we need to integrate the demands of both
performance and sound. Por ejemplo, in Symbiosis,
there is—toward the end—a stretch of three min-
utes for solo computer.
Otondo: There are also parts where it is almost
purely instrumental.
Barrett: Exactly, and in Symbiosis, this is one way
in which I balance the elements: to give both parts
solos and to have both coming together at important
meeting points. In those three minutes of solo com-
puter, the performer has to find a way to “compose”
herself. Everybody is looking at her, and she is a per-
former having to listen. In that section the theater
emerges as she demonstrates the act of listening and
not just sitting there waiting for the next thing to
happen. You see a string quartet play a piece with
computer or tape, particularly when they play with
a click track, and they look like they are thinking,
“When do I come in next? What time is it?"
Otondo: It looks like they are really uncomfortable.
Barrett: That’s right, so one trick is to find a way
for both parties to feel comfortable when the other
is soloing. Para mí, it is the potential in the sound
that makes the integration of the reality of the per-
formance and the reality of the sound possible.
Otondo: When you play a piece like this one live,
are you concerned with the issue of the balance of
the reproduced sound and the radiated sound from
the instrument? I feel that most live-electronics and
instrument-plus-tape pieces that I have listened to
in concerts have a problem in this respect. The lis-
tener gets a very fragmented spatial experience with
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the sound radiated from the instrument coming di-
rectly from the center and the sound coming from
the speakers from the sides. It is hard to integrate
everything spatially.
Barrett: Yes—well, integration is a two-fold problem.
There is the issue of composition, where you have
to consider spectra, gesture, and articulation, y
there is the issue of concert loudspeaker setup—
placing the equipment correctly in relation to the
performer and the space. You could refer to some
well-known pieces by Dennis Smalley, and you can
say they demonstrate a spectromorphological unity.
But then when it comes to the concert, if you use
speakers in one part of the hall and place the per-
formers elsewhere, this will result in a detachment
of sound sources. There is the practical aspect of
setting up the speaker rig so that these two layers of
acoustic and electroacoustic elements—of composi-
tion and performance—function. Para esto, it is nor-
mal to place a pair of speakers quite close to the
performers on stage as the primary projection of the
amplified acoustic sound (if this sound is amplified
en absoluto), or for the primary projection of live sound
transformación.
Over these speakers, we can also balance some of
the pre-made electroacoustic sound material. Como
more speakers are spread around the hall, then I dis-
tribute a little of the acoustic or live transformation
along with more of the other types of sound—such
as non-instrumental sound material or material
that if heard toward the back or in the surroundings
won’t feel detached from the performance. Este
means we can build a sound world where the instru-
mental sounds come from the direction of the per-
formadores, unless the conceptual aspect of the
composition demands otherwise.
Otondo: But don’t you think that is the easiest thing
to do—most composers detach the transformed
sound from the instrument’s sound. Like most of
the pieces we have listened to here at the ICMC in
Barcelona, we have sounds totally detached from
the radiated sound of the instruments. Don’t you
think that the hard thing to do is to try to integrate
the sound spatially and at a level of timbre? Es
hard to find pieces where it is done properly.
Barrett: I think we are looking at a difference in
aesthetic. In performance I often find that the North
American style is somewhat different from the Eu-
ropean style. Yet on a recording, I suppose it’s the
luxury of studio editing that maybe blurs these dif-
ferences in aesthetic.
Otondo: You are quite skeptical about this.
Barrett: Not at all. It’s a matter of taste. The style
that I hear at this ICMC uses the tape and computer
parts as if they were two separate “acoustic” instru-
mentos. The electroacoustic part contains articula-
tions and sounds which are strongly instrumental
in character. This type of material allows you to
spatially detach the electroacoustic from the live
part in that the electroacoustic becomes an “invis-
ible acoustic” performer. Whereas a conjunction of
textures and sound fields, of articulations and tra-
yectorias, I believe, stems from a different aesthetic
and a different compositional approach. A pesar de
my personal taste is with the latter (probably stem-
ming from my admiration of Varèse), I can defi-
nitely appreciate a good piece of music working
with the former aesthetic. Después de todo, it’s the music
that counts.
Referencias
austin, l. 2000. “Sound Diffusion in Composition and
Actuación: An Interview with Denis Smalley.” Com-
puter Music Journal 24(2):10–21.
Barrett, norte. 1999. “Little Animals.” Computer Music Jour-
nal 21(3):13-15.
Barrett, norte. 2002. “Spatio-Musical Compositional Strate-
gies.” Organised Sound 7(3):313–323.
harrison, j. 1998. “Sound, Space, Sculpture: Alguno
Thoughts on the ‘What,’ ‘How,’ and (Most Importantly)
‘Why’ of Diffusion . . . and Related Topics.” Journal of
Electroacoustic Music 11:12–20.
Otondo, F. 2005. “Some Considerations for Spatial De-
sign and Concert Projection with Surround 5.1.”
Paper presented at the 2005 Digital Music Research
Network Summer Conference, 21 December,
glasgow.
Truax, B. 1999. “Composition and Diffusion: Space in
Sound in Space.” Organised Sound 3(2):141–146.
Otondo
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