Early Computer Music Experiments in Australia and England

Abstract

This article documents the early experiments in both Australia and England to make a computer play music. The experiments in England with the Ferranti Mark 1 and the Pilot ACE (practically undocumented at the writing of this article) and those in Australia with CSIRAC (Council for Scientific and Industrial Research Automatic Computer) are the oldest known examples of using a computer to play music. Significantly, they occurred some six years before the experiments at Bell Labs in the USA. Furthermore, the computers played music in real time. These developments were important, and despite not directly leading to later highly significant developments such as those at Bell Labs under the direction of Max Mathews, these forward-thinking developments in England and Australia show a history of computing machines being used musically since the earliest development of those machines.

Full text

Early Computer Music Experiments in
Australia and England
PAUL DOORNBUSCH
Australian College of the Arts, 55 Brady Street, South Melbourne, VIC 3205, Australia
Email: pdoornbusch@collarts.edu.au
This article documents the early experiments in both Australia
and England to make a computer play music. The experiments
in England with the Ferranti Mark 1 and the Pilot ACE
(practically undocumented at the writing of this article) and
those in Australia with CSIRAC (Council for Scientific and
Industrial Research Automatic Computer) are the oldest
known examples of using a computer to play music.
Significantly, they occurred some six years before the
experiments at Bell Labs in the USA. Furthermore, the
computers played music in real time. These developments were
important, and despite not directly leading to later highly
significant developments such as those at Bell Labs under the
direction of Max Mathews, these forward-thinking develop-
ments in England and Australia show a history of computing
machines being used musically since the earliest development
of those machines.
1
1. INTRODUCTION
Music has always employed the latest technology to its
ends. For example, the technology of drawing metal
for strings made it possible to replace catgut for greater
brilliance and volume, nineteenth-century precision
manufacturing techniques of the day were used to
develop instruments such as the pianoforte, and in the
twentieth century there was the explosion of develop-
ments related to electrification. Music has always
taken maximum advantage of available technology.
Today it may seem obvious to use computers in all
aspects of music; from the creation of ideas and
creating the music, to the performance, recording and
reproduction process, computers are a ubiquitous and
integral part of the practice. However, in the early days
of computing, the machines were incredibly primitive
by today’s standards and turning their powers to music
was a leap few would have made.
In the 1940s, the calculations required by the
advancements in modern physics were unwieldy and
tedious. To help overcome this, calculating machines
had been developed, such as the ‘linear equations
machine’, the ‘differential analyser’and the ‘multi-
register accounting machine’(Hemstead and
Worthington 2005: 110; Hally 2006: 11–13). However,
the calculating machines still required significant
human intervention, so there was a desire to build an
automatic calculator with some sort of system to store
the data and the instructions for what to do with
the data.
There were some major technological advances at
the time that allowed the realisation of an automatic
calculator with memory. One such advance was the
use of thermionic valves (vacuum tubes), as switching
devices. The other major advance was storage or
memory systems such as mercury delay line ‘memory’
and the Williams Tube. Mercury delay line memory
had been used in radar systems during the Second
World War to process radar echoes. This memory
system could be adapted for use in an automatic
calculator, such as the Electronic Delay Storage
Automatic Computer (EDSAC) or the CSIR Mark 1.
Other early computers used different storage mechan-
isms, such as the Williams Tube, which used the
phosphor of a cathode ray tube to store digital data.
The first automatic computers were developed to run
calculations too cumbersome for humans with calcu-
lators to manage,
2
and also to organise and sort large
volumes of data. With this fundamental function in
mind, using a computer for music at all seems a rather
odd idea. Indeed, the first book on computer music,
Experimental Music by Hiller and Isaacson published
in 1959, several years after the developments discussed
in this article, says in chapter one:
Upon first hearing of the idea of computer music, a person
might ask: ‘Why program a digital computer to generate
music?’The answer to this question is not simple, since
such an undertaking immediately raises fundamental
questions concerning the nature of musical communication
1
The definition of a computer here means an all-electronic calculat-
ing machine with memory for the data and program; sometimes
called a stored-program machine. This definition is expanded upon
later, but the Manchester Small Scale Experimental Machine (Baby)
from mid-1948 is generally considered to be the first such machine.
There were several electronic and electromechanical programmable
calculators in the 1940s (e.g. Colossus, the Zeus machines and the
original ENIAC), which do not quite make the definition.
2
The term ‘automatic computer’may seem tautologous now, but in
the late 1940s and early 1950s the term ‘computer’referred to the
person who operated a calculator. In that era, the computing
department was a room full of people (often young ladies) running
computations with calculators. When the first programmable elec-
tronic computers came along, they were called ‘automatic’compu-
ters, to distinguish them from the person.
Organised Sound 22(2): 297–307 © Cambridge University Press, 2017. doi:10.1017/S1355771817000206
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and its relation to formal musical structures. (Hiller and
Isaacson 1959: 1)
Early computers produced more raw sound than any-
thing else: they did not have the sort of display we are
used to today, and they had electromechanical per-
ipherals producing large amounts of sound in opera-
tion. So perhaps using a very early computer to play
music was a more obvious and natural development
because of the often-rhythmical sounds from the
operation, and more easily imagined than using one to
create an image.
The interface of early computers was nothing like
today’s computers. There was no alphanumeric
keyboard for inputting information, and output was
usually punched paper tape, transferred to another
machine to print out text. There was little visual
feedback beyond status lights, and sometimes a view
into the memory on a cathode ray tube.
Several early computers included a loudspeaker used
to communicate where the program was during execu-
tion. For example, a sound could be programmed to let
the operator know the program had completed, or other
sounds could be programmed to keep track of the
execution of the program. Some of the computers that
included a loudspeaker were the Ferranti Mark 1,
Pegasus and Pilot ACE in England, UNIVAC-I and the
TX-0 (at MIT) in the USA, CSIRAC
3
in Australia, the
and others (Miyazaki 2012).
The audio interface of early computers was used as a
signalling or diagnostic aid for users. A programmer
would have the loudspeaker output a sound (called
‘blurts’by CSIRAC programmers) indicating a pro-
gram had completed or what stage had been completed.
Early computers were not very reliable and sometimes
produced erroneous results. Programmers would run a
program multiple times for an important calculation.
The poor reliability of early computers meant that
sometimes maintenance engineers and programmers
could hear a problem before it was noticed by other
means or erroneous output. One of the main engineers
of the BINAC and UNIVAC-I computers, Louis
Wilson, recalled that in 1949, to assess the state of the
machine he would listen to interference created on a
radio. He recalls:
When we were testing BINAC out, we were working two
shifts and we worked all night long, and we had a radio
going. After a while we noticed that you could recognize
the pattern of what was happening at the moment by
listening to the static on the radio. So I installed a detector
in the console and an amplifier and a speaker so that you
could deliberately listen to these things. (Miyazaki 2012)
This is not a unique occurrence. Frank Cooper, an
early computer engineer in England, recalls an event
from the early 1950s when a commissioning engineer
was sent to commission a new Ferranti Mercury
computer:
He was in his hotel room waiting to go onsite to do some
commissioning of a new Mercury, and he switched his
bedroom radio on, and what should come on but an
interview at the Bracknell weather centre: ‘This super new
computer […] is now about to forecast the weather!’And
lo and behold you heard some raucous semi-music com-
ing out of this computer, which was supposed to be the
computer forecasting the weather. However, Geoff, being
very familiar with the machine, recognised this music as
the overall test program, he also recognised that there was
a fault in the multiplier of the computer. (Burton 1995)
Such diagnostic listening has been part of human
behaviour for centuries. From the earliest medical
practice to machine operators and technicians, people
have used diagnostic listening to hear if there is an
abnormality; a mechanic will listen to the machine in
operation to determine what may be wrong. The
practice of using audio output as a diagnostic and
computer operation aid was not uncommon (Miyazaki
2012) as there were few other sensory interfaces, so it
was perhaps more of a natural development that
curious or creative programmers would try taking this
further and make a computer play music.
2. EARLY DEVELOPMENTS IN THE USA
The documented history of computer music is domi-
nated by the activity at Bell Telephone Laboratories in
the USA. By the end of the 1950s, the USA was a
country about 20 years out of the Great Depression
and a decade after the Second World War, with a
booming economy. This created an environment
where speculative research could thrive. At the New
Jersey Bell Telephone Laboratories in 1957, Max
Mathews and John Pierce started experiments with
making a computer synthesise waveforms. Utilising
the first commercial digital-to-analogue converter
(DAC), Mathews could synthesise any waveform
(Roads 1996: 10); digital synthesis is theoretically
unlimited and has unparalleled precision. However,
the most powerful machines took many hours of pro-
cessing to calculate a few seconds of sound waveform
‘samples’. The output was digital magnetic tape, which
could then be used with the DAC (Roads 2015: 93–4).
Mathews and Pierce applied the fundamentals of
analogue synthesis to digital synthesis, which had
applications in telephony. Pierce was a music enthusiast
who realised that understanding how much information
was in speech, and music, was useful for telephony
research. Mathews, after going to a concert with Pierce,
started writing the Music I program to perform music
on the computer through digital waveform synthesis
3
CSIRAC was originally known as the CSIR Mark 1 in Sydney, its
name was changed to CSIRAC when in Melbourne in 1955 (Door-
nbusch 2004). The names are used interchangeably, but I have
endeavoured to use CSIR Mark 1 for events from the Sydney time
and CSIRAC for other times.
298 Paul Doornbusch
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(Park 2009). The first people to use the program were
engineers. Mathews realised that composers would
make full use of the extended abilities, so he solicited for
composers to use the program. The composer James
Tenney was employed to work in the Audio Research
Department (Roads 1980). The requirements of com-
posers spurred the development of more advanced
MUSIC programs, culminating in MUSIC V, which is
the historical precursor of the current computer music
program Csound, and which was given away by Bell
Telephone Laboratories to universities to advance the
development of computer music.
While digital waveform synthesis and research into
computer music began in the USA in the late 1950s, this
was not the first time computers were used to play music.
In Australia the CSIR Mark 1 was programmed to play
music from about late 1950, and in England a Ferranti
Mark 1 computer played music from about late 1951.
Recently reported is activity from 1949 in the USA
(Stuutz 2015) that may or may not have occurred. There
were some similarities and differences in what happened
in the various locations. However, none of the early
groups had access to a DAC, and the computers would
have barely been capable of waveform synthesis if a
DAC was available. Also, the activity earlier than that in
Bell Labs was not done with the intent of exploring what
a computer might do for music, but rather as a
programming challenge, entertainment, or a trick.
Betty Holberton is reported to have programmed
the BINAC (Binary Automatic Computer) computer
to play music in 1949 (Stuutz 2015), although this is
doubtful. Another reported recollection of Holberton
programming BINAC to play music in 1948 (Kleiman
1997) must be an error –BINAC ran its first test
program in February 1949, but she mentions the
delivery party may well be August 1949, which is what
Holberton says in an oral history transcript (Tropp
1973: 169). Nancy Stern wrote the authoritative
history of BINAC in several books and documents, she
describes the Northrop Acceptance on 22 August 1949
in detail but does not mention it playing music (Stern
1979: 12). Given the detail and thoroughness in Stern’s
accounts, it would be an unusual oversight. Louis
Wilson used radio interference as a diagnostic aid in
1949 when working on BINAC (Miyazaki 2012). An
Associated Press article about BINAC on 22 August
1949 reports it calculating quickly (Altschull 1949: 7),
however, they do not report BINAC playing music,
which would be an obvious, spectacular event. Later in
the report, Eckert says a future computer (UNIVAC)
may play chess and write music as they can be descri-
bed mathematically; he discussed the future possibility
not what BINAC had done. Without evidence it is
impossible to prove or disprove Holberton’s claim.
Possibly BINAC played music around 22 August 1949,
but there are no other reports of this event and there
were good opportunities for it to have been reported.
3. EARLY DEVELOPMENTS IN AUSTRALIA
FROM 1950
In the late 1940s, Australia’s Council for Scientificand
Industrial Research (CSIR) embarked on a project to
build a fully electronic digital computer. Trevor Pearcey,
an English radio physicist, and Maston Beard, a
researcher at the CSIR Radiophysics Laboratory in
Sydney, designed the machine known then as the CSIR
Mark 1 (later known as CSIRAC) and it ran its first
program in November 1949. The CSIR Mark 1 was
a serial computer designed as a proof-of-concept proto-
type to be commercialised as a more powerful machine.
The first programmer was a mathematician called Geoff
Hill, who had assisted with the logical design of the
machine. Crucially, Hill came from a very musical
family, and he had perfect pitch. He programmed the
CSIR Mark 1 to play music from about late 1950.
As a serial computer, the CSIR Mk1 was thus very
different from today’s computers (Figure 1). A serial
computer will transfer data from ‘sources’to ‘destina-
tions’; for example, to and from memory, one bit at a
time. Modern computers move data around in parallel
chunks, typically 32 or 64 bits at a time. This difference
in the architecture of the CSIR Mark 1 (and other
similar machines) had significant consequences for
programming the machine and it is especially proble-
matic for applications with critical timing such as
playing music in real time.
While developments in Australia occurred in isola-
tion, the personnel involved were not cut-off from the
rest of scientific advances. Pearcey had worked in
England on advanced radar systems from 1940 to 1945,
becoming well acquainted with the contemporary
(electro) mechanical calculators. After the Second
World War he travelled via North America to
Australia. While in America he had contact with
researchers, some of whom were using large university
calculators in their work. He also had a chance meeting
with Howard Aiken, who had completed a machine
called the Automatic Sequence Controlled Calculator
(ASCC, also known as the Harvard Mk1) for IBM at
Harvard University. The ASCC was a very large com-
plex calculator, using relays and partially controlled by
a punched paper tape. In early 1947, Trevor Pearcey
and Maston Beard officially commenced the ‘Electronic
Computer’project. Also in 1947 the University of
Pennsylvania published the details of ENIAC.
The overriding considerations for the design of the
CSIR Mark 1 were engineering and programming
simplicity, as this was to be a prototype for a larger,
more capable machine. The designers decided on a
relatively small 20-bit word length, a serial architecture
and a moderate instruction-clock frequency of
1000Hz. The first program, a simple multiplication of
two numbers, was run late in 1949, probably in
November but nobody recorded the exact date. Trevor
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Pearcey recalls, ‘We all shouted “Hooray!”and went
back to work’(Doornbusch 2005: 3).
3.1. The Hoot instruction and the loudspeaker
The CSIR Mark 1 had a loudspeaker attached to one
of the serial ‘destinations’and a ‘hoot’instruction to
alert the operator when the computer needed some
sort of attention. By sending a string of pulses to the
speaker, a sound would be made to signal an operator.
It is unclear exactly how Beard and Pearcey
conceived of the loudspeaker. The original design
documents do not show it, but at the end of 1948
Pearcey travelled to England and saw computers there,
including the Manchester Mark I which had some sort
of hooter, and EDSAC which had a bell when the
STOP instruction was executed. Some first-generation
computers had a non-programmable hooter; an
instruction would trigger a fixed sound. Why Pearcey
gave the CSIR Mark 1 a programmable hooter is a
mystery and not documented anywhere (Doornbusch
2005: 19, 20). The Manchester Mark 1 did not
initially have a programmable hooter: the records
show the ‘hoot’instruction first appeared in the evol-
ving instruction set in February 1950 (NAHC 1951b;
Lavington 2016). Turing’s programming manual
for it mentions how a loop of instructions could be
used to make a sound (Turing 1950: 24), however,
there is no record of the Manchester Mark 1
being used to play any music, and Turing’s manual is
from 1950.
It is probable that Pearcey recognised the need for a
‘hoot’instruction, and implemented the simplest and
most pragmatic solution of providing a programmable
destination with a speaker attached. It is likely he saw
the hooter on the Manchester Mark 1 (even if it was
not programmable in 1948), and he simply copied the
idea without much thought, as a simple, obvious, and
direct solution. Pearcey planned for a programmable
hooter on the CSIR Mark 1, without realising it
offered the flexibility for a programmable frequency
output, if one could negotiate the programming gym-
nastics to achieve it.
As a serial computer, the CSIR Mark 1’s speaker
was built into the computer as a destination for data,
effectively on a register of the machine and it received
the raw pulse data off the ‘bus’. A single pulse would
produce barely a click, for audible output multiple
pulses would be needed. The notation used to send
pulses to the speaker was the ‘P’statement, and the
programmers would notate this as ‘->P’. Several
inline ‘P’statements could be put in sequence or they
could be organised as a short loop of instructions. The
timing of the pulses (and of the loop) would have
caused a change in the frequency of the sound from the
hooter. Any programmer with an interest in sound or
music would see the potential. However, there are two
difficulties with this: the major problem to be over-
come was the variable amount of time each memory
access took of the mercury acoustic-delay-line
memory. The other difficulty was the major clock fre-
quency of CSIRAC, only 1000Hz, and this granularity
Figure 1. CSIRAC on display for its 50th birthday celebrations in Museum Victoria. The hooter loudspeaker can be seen in
the right-hand door of the console. Image copyright the author.
300 Paul Doornbusch
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of instruction execution made generating pulses with
exact timing very difficult. The sequence of instruc-
tions could, for example, look like this:
start of note
set counter to x
loop start, send pulse to speaker
wait time t1
send pulse to speaker
wait time t1
send pulse to speaker
wait time t2
send pulse to speaker
wait time t3
send pulse to speaker
decrement counter
if x equal to zero then exit, else
return to loop
end of note
Achieving a steady stream of pulses to the speaker took
considerable effort, a very intimate understanding of
the machine’s operation, and the arrangement of data
and instructions in memory. Geoff Hill’s musical
knowledge was critical for him to program the CSIR
Mark 1 to play music. Being a mathematician, he
would know if he could send the hooter pulses with a
regular period, it would make a steady pitch. Later, if
the pulse-periods could be organised enough, it could
play the notes of a diatonic scale.
Initially, playing music on the CSIR Mark 1 was a
tremendous programming challenge. Naturally, Hill
and the others programmed the CSIR Mark 1 to play
popular melodies. They were engineers and scientists
not specialist composers. The first song on the CSIR
Mark 1 ‘Music Program’tape (a punched-paper tape),
after a major scale, was Colonel Bogey, the popular
wartime song. There are several references putting the
first music on the CSIR Mark 1 as late 1950 or early
1951. Trevor Pearcey has been interviewed on video
saying the music was a very early programming exercise
in 1950 or 1951 (Doornbusch 2005: 24). Dick McGee,
in an interview with the author, also remembered the
music at the computing conference on 7–9 August 1951,
but also in April 1951 when he started with the CSIRO
(Doornbusch 2005: 25). There are other personal
stories placing the CSIR Mark 1 music in very early
1951 or late 1950. This is strong evidence for putting the
CSIR Mark 1 among the first computers to play music.
Significantly, this happened six to seven years before the
developments at Bell Labs, and it was real-time
computer music unlike the work at Bell Labs.
However, there were developments in England at about
the same time, and at least talk of something similar in
the USA.
To the engineers, programming the CSIR Mark 1 to
play music was a technical challenge in computation;
the programmers were not investigating what this
meant for creativity or the future of music. Sadly, it
could have been otherwise. Percy Grainger was one of
Australia’s more adventurous composers with an
interest in advanced music and he came very close to the
CSIRAC when it was at the University of Melbourne in
1957. The staff of the computation laboratory would
watch him walk past and say, ‘There goes Percy
Grainger!’(Doornbusch 2005: 82). Unfortunately they
never thought to show him CSIRAC playing music and
discuss the possibilities with him.
4
Grainger had devel-
oped Free Music Machines from the mid-1940s with
rudimentary electronic synthesis techniques and had an
acknowledged interest in music and the possibilities
afforded by technology. The involvement of musicians
(composers) with engineers is one of the crucial points
of difference with the later developments in the USA
and the great advances there.
4. EARLY DEVELOPMENTS IN ENGLAND
FROM LATE 1951
Modern computing began in England in the mid-
1940s, with the earliest machine recognisable as a
computer by a modern definition
5
being the Small
Scale Experimental Machine (SSEM) at the Victoria
University of Manchester. The ideas spread quickly to
other parts of the world where there was a need to
perform large volumes of calculations or manage large
amounts of data. Many early computers had simila-
rities (such as the serial architecture, or mercury delay-
line memory) dictated by the availability of technology
to perform a particular task.
While the early computing developments in England
are well documented, the music programmed on the
early machines is practically unknown and undocu-
mented. The Small Scale Experimental Machine
(SSEM, operational mid-1948) in Victoria University
of Manchester was further developed and improved to
become the Manchester Mark 1 (operational mid-
1949). Ferranti commercialised this design in 1951 as
the Ferranti Mark 1 computer (Figure 2), and it was
the world’sfirst commercially available general-
purpose computer (Allison 2003).
4
Sound examples of the accurately reconstructed CSIRAC music (it
was never recorded) are available online at www.doornbusch.net/
CSIRAC/index.html.
5
The history of computing shows a continuum of developments for
several hundred years, and the distinction between a programmable
calculator and a computer can be fine. However, from a modern
perspective, a computer (as described by Turing in 1936 and von
Neumann in 1945) is an all-electronic digital machine, with electro-
nic memory containing data and instructions, and with a branching
instruction.
Early Computer Music Experiments in Australia and England 301
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Christopher Strachey, research physicist at STC
during the Second World War who’sfatherworked
with Alan Turing as a cryptographer, had an interest in
computing. A schoolmaster after the Second World
War, Strachey was given a copy of the 1950 program-
ming manual for the Ferranti Mark 1 by his friend
Turing (Burton 1995; Hally 2006: 100). In 1951 Stra-
chey developed a program to write love letters by
picking random words; Strachey’ssignaturefirst
appeared in the logbook on 25 September1951 (NAHC
1951a; Lavington 2016). He also wrote a program to
play draughts, completed in October 1951, and at the
end of the program it played the national anthem, ‘God
Save the King’. Soon after, other programmers wrote
programs to play music, thetunes played were ‘Baa Baa
Black Sheep’,‘In the Mood’, and so on. It was this
program the BBC recorded and is recognised as the first
recording of a computer playing music.
Turing’s 1950 programming manual mentions the
hoot instruction and the possibility of making a note
‘rich in harmonics’with a pitch about middle C (Tur-
ing 1950: 24). However, Turing did not describe the
process of making the Manchester Mark 1 or the Fer-
ranti Mark 1 play music, he only described the ‘hoot’
instruction as a way to signal an operator. Strachey,
took the next step to make the Ferranti Mark 1 play a
steady note and melody, thus doing the same work
Geoff Hill did in Australia to get the machine to play a
recognisable melody.
In September 2016, researchers in New Zealand
reported they had restored the recording made of
Strachey’s program playing music (France-Presse
2016). The existence of the recording is not new
information; the BBC reported it in 2008 (Fildes 2008),
it is also mentioned in 1995 (Resurrection the Compu-
ter Conservation Society UK bulletin, issue 12) and
2005 (Doornbusch 2005: 21). The recording was on a
78 rpm acetate disk (a vinyl ‘master’) and the report
discusses the cleaning of this recording of the inevitable
crackles and pops from the analogue recording format,
to hear the original recording closer to how it would
have sounded in late 1951. Such restoration is a stan-
dard software function now. There are many inac-
curacies in a Guardian article: it claims the music was,
‘Played on a gigantic contraption built by the British
computer scientist Alan Turing.’However, it was
played on a Ferranti Mark 1, as noted by Frank
Cooper, who was there, and it was not created by
Turing despite what the headline says (Burton 1995,
2016). The article also says Turing was a musical
innovator and makes other similar claims, but there is
no evidence for such claims and it is Christopher
Strachey who took the steps to use the ‘hoot’instruc-
tion to create music. To illustrate what Turing
achieved, Turing’sentire documentation of the hooter
in the 1950 Programming Handbook for Manchester
Mark 1 Electronic Computer (which also suited the
Ferranti Mark 1) is reproduced here:
9.2 The hooter
When an instruction with function symbol /V is obeyed an
impulse is applied to the diaphragm of a loudspeaker. By
doing this repeatedly and rhythmically a steady note, rich
in harmonies, can be produced. This is used to enable the
operator to be called to attend to the machine in some
way. The simplest case is where the whole of a job is
Figure 2. Ferranti Mark 1 computer with some of the many cupboards open and console. The hooter loudspeaker was to
the side of the console and cannot be seen. Image courtesy of the University of Manchester.
302 Paul Doornbusch
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completed and it is required to clear the electronic stores
and start something different. All that is then required is
to repeat a cycle of instructions including a hoot, e.g.
FS NS/V
CS FS/P
In this case every second instruction will put a pulse
into the speaker. These pulses will occur at intervals of
8 beats i.e. 1.92 ms giving a frequency of 521 cycles
(about middle C). Or one could use the loop of three
instructions
O@ /V
G@ P@/V
M@ G@/P
which gives a slightly louder hoot a fifth lower in
frequency. Single pulses applied to the loudspeaker are
distinctly audible as something between a tap, a click, and
a thump. This fact can be turned to good account. By
putting hoot instructions into programmes at suitable
points one is enabled to ‘listen in’to the progress of the
routine. Some indication of what is going on is given by
the rhythm of the clicks that are heard. (Turing 1950)
This description could be said to allude to using the
hooter to play at least musical notes, but only as signals
about the machine’s operation. As musical intervals are
ratios, and Turing was a savant mathematician, it is
also reasonable that Turing understood the timing of
the instruction loop and expressed the ratios of the
two frequencies as a musical interval in common usage.
The description avoids the complexities required to
produce a scale (the finely tuned delays between the
pulses), and Strachey made the leap to make the
machine play a musical scale and produce recognisable
melodies.
Listening to the music played by the Ferranti Mark 1
(Burton 1995), and reading Turing’s manual, it would
appear the sound production method was the same as
on CSIRAC. The Ferranti Mark 1 used different
memory technology to CSIRAC, the Williams Tube,
which may have had improved access times, but this is
currently unknown and worthy of further research.
Williams Tube memory is random-access whereas delay
line memory is sequential-access, and timing critical
applications are inherently easier to program with
random-access memory. The memory technology con-
tributes greatly to the programming difficulty in
achieving a steady and accurate pitch from the hooter,
as does the main clock frequency of the machine.
A recording of the Ferranti Mark 1 computer
playing music, along an interview in which Frank
Cooper discusses the recording, may be found online.
6
In another significant early development in England,
unreported at least in the electronic and computer
music communities, the National Physical Laboratory’s
(NPL) Pilot ACE computer (operational in mid-1950)
played music autonomously from around 1952
Figure 3. Pilot ACE computer. Image courtesy of the NPL.
6
Recording of Ferranti Mark 1: http://curation.cs.manchester.ac.uk/
digital60/www.digital60.org/media/mark_one_digital_music/index.
html. Interview with Cooper: http://curation.cs.manchester.ac.uk/
digital60/www.digital60.org/media/interview_frank_cooper/index-2.
html (accessed 17 January 2017).
Early Computer Music Experiments in Australia and England 303
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(Figure 3). Designed by Alan Turing, the Pilot ACE
was the prototype machine for the full ACE (Automatic
Computing Engine), and it had a programmable hooter
similar to the Ferranti Mark 1. Mercury acoustic delay
line memory was used on the Pilot ACE, giving it
variable instruction timing, similar to CSIRAC.
Most interesting is that the Pilot ACE had program
routines that would allow it to create its own music.
Davies reports:
The ACE Pilot Model and its successor, the ACE proper,
were both capable of composing their own music and
playing it on a little speaker built into the control desk.
I say composing because no human had any intentional
part in choosing the notes. The music was very interesting,
though atonal, and began by playing rising arpeggios:
these gradually became more complex and faster, like a
developing fugue. They dissolved into coloured noise as
the complexity went beyond human understanding.
(Davies 1994: 19)
Diagnostic routines were built into the Pilot ACE,
some sent pulses to the speaker. One diagnostic tool
was a console meter triggered by data transfer
instructions, used as a crude measure of program
complexity and machine efficiency (fewer data
transfers meant greater efficiency). However, the
signal driving the meter had a higher frequency AC
component obscuring the average reading, so Davies
filtered this out to make the meter readings clearer, and
out of curiosity sent it to the speaker. This was not
initially intended to make music, but rather as a diag-
nostic aid, so programmers and operators could have
an indication of efficiency. This was a kind of diag-
nostic listening as previously discussed, but it was also
a kind of sonification of the machine’s activity.
Another engineer, David Clayden added switches
to aid in program testing and debugging, allowing the
internal data or instructions to be changed. While
testing this new facility the engineers accidentally dis-
covered the ability to trick the machine into making
music by overwriting memory. Davies recalls:
The program would be in a loop and therefore give a note
from the speaker. By fixing the operation to add into a
suitable bit in the instruction delay line, this counter
would spill over into the timing fields and periodically
enter a new kind of loop. Using the right switch settings
made the loop size stay constant for a while (a note), then
abruptly change in size.
Loops were always multiples of 32 microseconds long, so
notes had frequencies which were submultiples of 31.25
KHz. The music was based on a very strange scale, which
was nothing like equal tempered or harmonic, but was
quite pleasant.
Initially the playing was rather slow, as though it was
simply familiarising the listener with its unorthodox scale.
Higher up the scale, when the notes are a bit high even for
young ears, the spilling over process gets more complex.
It is next to impossible to work out what is going on in the
delay line, with the instructions changing all the time.
The next bars of music are a little faster and the same scale
of notes appears, generally rising but now varied in
sequence like an arpeggio. This repeats with ever faster
and more complex patterns until it becomes too fast and
complex to follow. Once you get used to the strange scale
it really sounds musical and even intelligent.
We were amazed when we first heard it. To get a nice
composition you had to choose the right setting on
David’s switches, and the settings for the interesting music
were rather critical. Some switch settings gave falling
arpeggios. (Davies 1994: 20)
This would appear to have been in the early 1950s,
approximately 1952–53, as the Pilot ACE was shut
down in 1955, and the full ACE machine was opera-
tional in 1957. Davies describes this event just as the
computer was being readied to move to a new home as
a service computer.
This seems to have been a happy accident, rather
than an early planned exercise in computer-aided
algorithmic composition. However, this seems to
have happened before the computer-aided composi-
tion experiments by David Caplin and Dietrich Prinz
in the mid-1950s (Ariza 2011), and quite some time
before the highly documented and rigorous work of
Hiller and Isaacson.
5. DISCUSSION
It seems like a small distinction, but these computers
did not just play music on their own, the personnel who
programmed them and used them made the computers
play music. The programming required was extra-
ordinary; it was convoluted and an order of magnitude
more difficult than what was required for other
computation tasks. Humans enjoy a challenge, and
this was a programming challenge par excellence; to
send regularly timed pulses to a speaker from machines
with variable and unreliable timing for many things,
including memory access. So it is extraordinary
programmers were bothered (also with the Bell Labs
developments, but at least there it may have had
applications to their main business). The programmers
in both Australia and England must have had a great
interest in music (as they did in the USA), and also
in the machines, to develop programs to play music.
It was an extraordinary effort.
In Australia in the very early 1950s, the CSIR
Mark 1 playing music was initially a programming
challenge, it was also seen as a diversion and a trick of
the computer (Doornbusch 2005: 25). By the late
1950s, the music played by CSIRAC was seen as an
amusement and people were more impressed with its
calculating abilities (Doornbusch 2005: 45). In a young
304 Paul Doornbusch
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country focused on primary production, the music was
never seen as something worthy of serious investiga-
tion. Also, when the CSIR Mark 1 was in Sydney
(1949–55) it was part of the CSIR Radiophysics
department, which was undergoing a realignment of
proprieties. The CSIR Mark 1 was always intended to
be a prototype machine to be commercialised outside
the CSIR, thus concluding the project. The main per-
sonnel involved with the CSIR Mark 1 were trying to
popularise it through the music to save the project.
CSIR management of course resisted this, so the music
played by the CSIR Mark 1 was never recorded or
broadcast. The music developments with CSIRAC
were not seen as leading to any productive activity, so
they were not pursued any further beyond the novelty
value and programming challenge of making a com-
puter play music.
There is good evidence of the CSIR Mark 1 playing
music either late in 1950 or very early 1951, and there is
also good evidence that Christopher Strachey pro-
grammed the Ferranti Mark 1 to play music slightly
later, probably mid-September 1951. Strachey’s music
output was recorded in November of 1951, and the
CSIR Mark 1 played music publically in September
1951, but there was activity before these public events.
The music played by the Ferranti Mark 1 in England
was also seen as a trick (Burton 2016). The music was
unrelated to the ‘serious’business of performing
calculations for advanced physics and engineering.
Similarly, the engineers and management of the Pilot
ACE did not see the musical output as worthy of
further investigation, which is understandable in a
country still recovering from the Second World War.
In light of the foregoing, it is unsurprising that the
early computer music developments in Australia and
England did not lead to any further investigation such
as those from the early work at Bell Labs. The history of
computer music celebrates the developments in the
USA, mostly by Max Mathews, with justification. The
early work in Australia and England is often over-
looked, despite the fact that computer music activities
there began some six years earlier than in the USA, and
they played music in real time; something that did not
happen in the USA until many years later.
There are several reasons for celebrating the USA
developments over those in Australia and England.
The main reason is that the work in the USA was
designed from the outset to explore the possibilities of
computer music and led to numerous future develop-
ments, while in Australia and England it was an amu-
sement only. The early developments in Australia and
England occurred before the availability of a DAC,
so there was no flexibility in the sound production and
thus less obvious potential. The only group that would
have seen this as useful would have been advanced or
experimental composers, but they were not involved
and unaware of the potential.
Digital waveform synthesis with a DAC allows any
waveform to be synthesised with excellent control and
precision, with obvious potential for sound synthesis
regardless of how costly it was of computer resources
and time. In America, Max Mathews realised engi-
neers were not excellent musicians and, crucially, he
advertised for composers to become involved with the
project. In an interview in 1980, he recalls:
When we first made these music programs the original users
were not composers, they were the psychologist Guttman
and John Pierce and myself, who are fundamentally scien-
tists. We wanted to have musicians try the system to see if
they could learn the language and express themselves with
it. So we looked for adventurous musicians and composers
who were willing to experiment. The first one was David
Lewin, who was at Harvard at the time. We corresponded
and he did a composition mostly by mail, which
was a brave thing to do. Then John Pierce met Jim Tenney
at the University of Illinois, where Tenney was studying
with Hiller. Pierce was very much impressed with
Tenney’s music and his interest in computers. He invited
Tenney to take a temporary job at the Laboratories to try
out the music programs. Tenney took the job and
developed some timbres of his own and also some pieces.
(Roads 1980)
Clearly, Bell Telephone Laboratories (at least Pierce’s
group) was the sort of company to see potential and
value in such a speculative venture. To meet composers’
needs, Mathews developed software with additional
flexibility and functionality. However, this did not hap-
pen in England and Australia, where the developments
occurred too early to use DACs and such speculative
research was unsupported. Bell Labs started the first ever
project with the intent of exploring the possibilities of
computer music and a composer was employed to work
with the researchers. These combined factors had the
effect of keeping the developments in Australia and
England unknown for decades; they did not lead to
further developments and in modern terms the results
were very unsophisticated. The early work of Christo-
pher Strachey in England is still not well researched or
documented, and is an area for further investigation.
There are other developments in electronic music
from Australia and England that are also largely
ignored, such as the film sound experiments of the early
1930s by Jack Ellitt and the electronic music machines
and pieces by Percy Grainger. Ellitt and Grainger chose
to follow their experimentalist dreams by emigrating (to
Europe and America respectively) where they could be
with more like-minded individuals and engage in their
practice. Grainger at least made regular trips ‘home’
and attempted to engage with his original culture. Per-
haps these people and their work are less known
because they did not inspire further developments, or
because they occurred in a cultural context where such
radical ideas could not take hold.
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6. CONCLUSION
The history of electronic and computer music is made
of many small and often uncoordinated steps; the
developments discussed above are some of those steps.
While these developments did not lead to the
enormous advancements that happened at Bell Labs
under the direction of Max Mathews, they are none-
theless noteworthy. The developments in England and
Australia show that, at the very least, people seem to
have a natural predisposition to turn anything new to
the production of music. When discussing the CSIR
Mark 1 developments from 1950 with Max Mathews
in 2000, Mathews wrote:
I found it very interesting and the implications about
human beings most encouraging to me, the most
impressive thing was the shortness of the time between
the development of a computer powerful enough to make
any kind of musical sound and the actual production of
music with the computer. I think this shows how funda-
mental and important music is to human beings. (Math-
ews 2000)
When we first chatted about the CSIRAC music,
Mathews instantly asked about the memory
architecture of CSIRAC, and when I told him, he
groaned and said how ‘hard’it would be to get a
steady note from CSIRAC; he immediately
understood the implications and the difficulty of
the task.
While in Australia and England the first steps were
taken to make a computer play music, and also to
create music independently, there was not the tech-
nology for arbitrary waveform synthesis (via a DAC)
or the cultural environment to see the potential benefits
of this. Australia in the early 1950s was focused on
primary industry, and technology was viewed as either
supporting that end or it was unnecessary. Similarly,
England was emerging from the Second World War at
the time and focused on rebuilding a shattered country.
Thus, CSIRAC or the Ferranti Mark 1 or the Pilot
ACE playing music was a fun ‘trick’and a useful
programming challenge or tool, but it was not seen as
impressive as the raw calculation ability of the
machines and it could not be seen as a useful under-
taking for societies either building a new country or
rebuilding an old one.
ACKNOWLEDGEMENTS
I am indebted to several people who have helped to
ensure the accuracy of this article: Chris Burton and
Simon Lavington of the UK Computer Conservation
Society, also Cort Lippe, Curtis Roads and Peter
Thorne. I am very grateful for their generous assis-
tance, which has helped to improve this article and
ensure its accuracy.
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