This paper discusses a semi-improvised compositional approach, within a hybridised electroacoustic music context. It will feature a live presentation and discussion of a novel form of professional application to expand contemporary, artistic practice. A central component of this approach is a discussion of the Analogue Shift Register (ASR) including its various digital representations. Historically the ASR emerged during the early 70s with the first example by Serge Tcherepnin, described as a '.. sequential sample and hold module for producing arabesque-like forms in musical space'. A contemporary realisation of the ASR can be found in devices such as Ornament and Crime's (O&C) CopierMaschine and Turing Machine (Music Thing Modular/Tom Whitwell). The Shift Register, whether analogue or digital, as part of a composing/writing practice can be a potentially more engaging vehicle, due to its self-generative capabilities, than perhaps a sequencer would be for many practitioners. Whilst it is a slightly more 'esoteric' device, the lines or patterns developed using these systems can in turn be resampled and integrated into various types of composition. As a practical aid the device can seed results applicable to any electroacoustic medium whether for stage, recording studio or live performance. Outputs can be managed with varying levels of granularity and artists can produce innovative results when combined with knowledge of harmony, oscillator tuning, cv quantisation, alongside the exploration of various generative algorithms. Assisted by these devices, the performer/composer would be able to extend their practice to generate structurally complex pieces using a novel approach that hasn’t previously been realised or considerably experimented with alongside contemporary music making tools The presentation will demonstrate some approaches that allow for original work to be devised using a modular synthesiser as part of the compositional/songwriting process and will enable discussion of the relative merits of this novel form of professional application.

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Improvising Songwriting and Composition Within A
Hybrid Modular Synthesis System
Author: Hussein Boon
Author Correspondence: h.boon@westminster.ac.uk
ORCID: https://orcid.org/0000-0003-3380-9474

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Introduction
The use of Ornament and Crime
(o_C) CopierMaschine, implementation of an Analogue
Shift Register, as a performative and
writing/composition tool.

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Introduction
history of Shift Register
general information
concerning operation
discussion of potential
application
example case studies from
my own improvising and
writing approaches

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Introduction
The Shift Register is broadly applicable to any
style or genre and is an equally interesting tool
from which to make samples such as Liquid Drum
and Bass or for those requiring an immediate
Reich/Glass (Gleiss?) like composition tool

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History
The Shift Register is in the domain
of sequencing technologies
Analogue Shift Register (ASR)
emerged during the mid 70s
evidence that custom modules,
Fortune Modules, built by Fukushi
Kawakami for the composer Barry
Schrader (Shrader, 2019)

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first available commercial
unit for the Serge
Synthesizer System
described as a '.. sequential
sample and hold module for
producing arabesque-like
forms in musical space'
origins in Bucket Brigade
Device (BBD an Sample
and Hold (S&H) module
History

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BBD
The Bucket Brigade Device,
developed by Phillips Research
Labs (Computer Music, 2019) at the
end of the 1960s, allowed a stored
analogue signal to be shifted, or
shuttled, through a series of
capacitors updated each clock cycle.

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S&H
The Sample and Hold circuit
captures (samples) a dynamic
voltage source updated every
clock cycle.
…, the S/H can “look” at a
continually changing voltage
source such as the output of an
audio oscillator or LFO, noise,
an envelope, keyboards, etc.
(Strange, 1973, pp.80)

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Arabesques In Space
The arabesque patterns promised by the literature
resulted from passing a dynamic waveform, such
as Sine or Triangle, into the module, sampled with
a fast enough clock or gate signal to produce an
output that closely mirrors the waveform shape.
When outputs are patched to two or more
oscillators these will appear to 'chase' each other
in sync very much like a Quadrature LFO or
'leaping salmon'.

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Random
Composition
When considering using a Shift
Register or S&H device, users will
have to accept that randomness
will be formulated as part of their
working practice.
For those working in areas of
Generative Composition this can
be a fruitful area for exploration.
“Note that a slight change in the
relative frequencies of the two
waves can have a profound effect
on the output sequence.”
(Chamberlin, 1987, pp.327)

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A Canonic Utility
Shift Register - sort of canonic utility device
with outputs shaped by a combination of:
Waveform shape
Waveform amplitude
Clock interval cycle
Some semi-randomness due to it being
“designed as a sequencer that you can steer
in one direction or another, not one that you
can program precisely.” (Whitwell, 2012a).

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CopierMaschine
CopierMaschine app extends the original Shift Register
“ASR mode works as a cascaded, four-stage sample-and-
hold module” (Stadler et.al, 2016a) with innovations
 self generating internal sampling CV sources
 quantisation algorithms
 Scale mask and scale rotation
 Freeze (Hold) function

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Performance
Approaches
A number of approaches
possible including:
Electro continuo
Combinatorial/Prominent
Voice
Discontinuous/Disrupted
Clocks

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Freeze Function
Use of Freeze function as means of
identifying a malleable 'hook'. Variation
mediated by:
Scale rotation
Gain – consider this as similar to
headroom but managing voltage/value
range
Relative Osc levels

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Conclusion
Overall, this module opens up a wealth of
possibilities in terms of design workflow enabling
experimentation to generate different performed
composition outputs that are not products of the
more traditional keyboard, guitar or even DAW
paradigm and is highly applicable in any
contemporary songwriting, composition,
improvisation, recording or media context.

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References
Bjorn, K. and Meyer, C. (2018). Patch & Tweak, Denmark, Bjooks, p. 253.
Chamberlin, H. (1987). Musical Applications of Microprocessors, Indiana, Hayden Books, pp. 326-
328.
Ciani, S. (1976). Report to National Endowment Re: Composer Grant, University of Victoria.
Available from
https://people.finearts.uvic.ca/~aschloss/course_mat/MU307/MU307%20Labs/Lab3_BUCHLA/Susan
ne%20Ciani%20Buchla.sm.pdf [Accessed 30 November 2019].
Computer Music. (2019). A brief history of bucket-brigade delays (and 4 great plugin emulations),
Music Radar (website), available online from https://www.musicradar.com/news/a-brief-history-of-
bucket-brigade-delays-and-4-great-plugin-emulations [Accessed 30 November 2019].
Hard Sync. (2019). A brief history of Analog Shift Registers (ASR), Hard Sync, March 2009. Available
from http://hardsync.blogspot.com/2009/03/brief-history-of-analog-shift-registers.html [Accessed 30
November 2019].

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Shrader, B. (2019). The Fortune Modules, Barry Shrader (website), available online from
https://barryschrader.com/the_fortune_modules/ [Accessed 30 November 2019].
Stadler, M., Dowling, P. and Churches, T. (2016a) Ornament and Crime User Manual for v1.3,
Ornament and Crime, 2016. Available from https://ornament-and-cri.me/user-manual-v1_3/ [Accessed
30 November 2019].
Strange, A. (1972). Electronic Music: Systems, Techniques and Controls, USA, W.C. Brown.
Waltari, M., and Halonen, K. (2003) Sample-and-Hold Operation, Circuit Techniques for Low-Voltage
and High-Speed A/D Converters. The International Series in Engineering and Computer Science
(Analog Circuits and Signal Processing), vol 709. Springer, Boston, MA, pp.19-21.
Whitwell, T. (2012a). 22 things to know about the Turing Machine, Music Thing Modular, 2012.
Available from https://musicthing.co.uk/pages/turing.html [Accessed 30 November 2019].
References

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Thank You
Author: Hussein Boon
Author Correspondence: h.boon@westminster.ac.uk
ORCID: https://orcid.org/0000-0003-3380-9474
Further information and book
here: https://www.routledge.com/Innovation-in-Music-
Future-Opportunities/Hepworth-Sawyer-Paterson-
Toulson/p/book/9780367363352