BACHELOR THESIS
The Relationship of Audio Signal Processing and Musical Complexity
Robert Eklund
Bachelor of Arts Audio Engineering
Luleå University of Technology
The Relationship
of Audio Signal Processing
& Musical Complexity
By Robert Eklund, Luleå University Of Technology, 2012
Abstract
This essay studies the relationship of audio signal processing and musical complexity, focusing on minimalistic electronic music. Minimalistic electronic music is a genre that builds on repeating monotonous music patterns, and is perceptually “low complexity” music. The song structure is often dependent on audio signal processing, used almost as a musical instrument to increase or decrease the intensity of the song. This essay investigates if audio signal processing might increase the perceived complexity of a low complexity music pattern (such as minimalistic electronic music).
This is investigated by doing a literature review and a listening experiment. The literature review, which is on music history and musical complexity, showed that the evolution of minimalistic electronic music is correlated to the evolution of audio technology, and that it is likely that audio technological advancements has induced minimalist approaches to popular music production.
The listening experiment was a modified MUSHRA-test where subjects listened to rhythmical patterns of various complexity, played with and without audio signal processing. Although few results could be verified with confidence intervals at α = 0.05, it could be concluded that there are tendencies of perceived complexity being increased by audio signal processing. Audio signal processing also seemed to have a greater effect on low complexity music than on music of higher complexity. This shows that there might be perceptive reasons behind the extensive audio signal processing in minimalistic electronic music.
Table Of Contents
1.Introduction...1
1.1.Audio Signal Processing ...1
1.2.Musical Complexity...1
1.3.Minimalistic Electronic Music...1
1.4.Research Question...2
1.4.1.Main Research Question...2
1.5.Aim...2
1.6.Objective...3
1.7.Analysis Questions...3
2.Literature Review...4
2.1.Auditory Attention...4
2.2.Perception, Interpreting Patterns...5
2.3.Musical Complexity...6
2.4.Minimalism In Electronic Music...7
2.5.Music Examples of Minimalistic Electronic Music...9
2.6.Minimalism and Perception...10
2.7.Electronic Music and Audio Technology...12
2.8.Discussion of Audio Technology's effect on Minimalism in Electronic Music...15
2.9.Conclusions...16
3.Method ...17
3.1.Prominence ...17
3.2.Modified MUSHRA-test...18
3.3.Procedure...18
3.4.Stimuli...19
3.4.1.Complexity Categories...19
3.4.2.Measuring the Complexity of the Stimulus...20
3.4.3.Calculated Patterns...22
3.4.4.Audio Signal Processing Degrees...24
3.4.5.Specifications of the Audio Signal Processing...24
3.5.Subjects...26
4.Results and Analysis...27
4.1.Results and Analysis Introduction...27
4.2.Test A...27
4.3.Test B...29
4.4.Analysis A)...33
4.5.Analysis B)...33
4.6.Analysis C) ...33
5.Discussion...34
5.1.Reliability...34
5.2.Validity...35
5.3.Ecological Validity...35
6.Conclusions...37
7.Reference list ...38
7.1.Bibliography...38
7.2.Software...39
8.Appendix...40
8.1.Complexity Calculation, Notation and Tables...40
8.2.Test B, Data Tables...43
1. Introduction
This is an essay that investigates the relationship of audio signal processing and musical complexity. Audio signal processing, being the use of audio technical equipment to alter or add details to a sound, and Musical Complexity, being a theory of how easy or hard it is for the human mind to perceive a logical structure from a musical pattern. These two phenomenons are from widely different fields of literature (technical writings and cognitive-science), and are usually not discussed as having anything to do with one another. But despite this, they actually do co-exist professionally in music production. Within music production, different professions contribute to different aspects of the music. The musician handles the musicological properties of a song, while the audio engineer handles the audio properties of a song. Perhaps, it is because of that these two phenomenons are segregated by these two different professions that they are often discussed as separate topics. But in this day and age, when computers allow musicians to become engineers and engineers to become musicians, it is perhaps time that that it is investigated how one affects the other.
1.1. Audio Signal Processing
When an audio engineer applies audio signal processing to a sound, the aim is to improve the aesthetic or technical qualities of the sound. The audio engineer might alter the balance of the frequency spectrum with an “Equalizer” (EQ), alter dynamics with a “compressor” or apply reverberation with “reverb” or “delay”. This would be done to shape the aesthetic properties of the sound. But the engineer might also fix technical problems, such as reducing unwanted noises or operate audio equipment to transmit the audio signal as true to the original quality as possible.
1.2. Musical Complexity
As for musical complexity, different music genres can be said to have different types of musical complexities, as has been investigated by Muir & Walker (2008). The more repetitive and predictable a musical pattern is, the easier it is for the human mind to understand it as music, but perhaps it will also become less interesting to listen to. On the contrary, music that is unpredictable and in-consequent may be perceived as more interesting and sometimes even confusing. Madsen &
Widmer (2006) even suggest a computation that can predict which notes of a musical piece that represent the lead melody, by measuring the complexity of its musical patterns.
1.3. Minimalistic Electronic Music
The scope of this essay will be on one specific genre of music, which is; minimalistic electronic music. Minimalistic electronic music is particularly interesting to the subject, because it has a very distinct low musical complexity, which makes it suitable to study from a musical complexity point of view. This genre is also interesting from the audio technical point of view, because its musical structure actually relies heavily on audio signal processing. Contrary to conventional pop music structures (such as verse, bridge, refrain, etc), minimalistic electronic music uses so called “breaks”
and “build ups”. The musical features of the song are brought to a minimum during the break, and then successively increases in audio technical features during the build up (often adding extensive amounts of reverb and delay). When the build up reaches it maximum, and audio effects are
essentially everywhere in the mix, things are yet again brought to a minimum, repeating the process.
It almost seems as though in this genre, audio signal processing is helping the musical structure to increase or decrease the intensity of the song. But does this mean that audio signal processing is also altering the musical complexity of the song?
1.4. Research Question
Could it be that audio signal processing increases musical complexity, which catches our attention in the same way that high musical complexity often represented the lead melody in the study by Madsen & Widmer (2006)? This thought forms the main research question question of this essay;
1.4.1. Main Research Question
Does audio signal processing alter the perceived musical complexity of rhythmical patterns?
The research question is narrowed down to rhythmical percussive patterns only, for the convenience of the listening experiment of this essay, that will be discussed later on.
The research question brings up some other intriguing thoughts. If audio signal processing actually does increase musical complexity, is it then possible that the low musical complexity of
minimalistic electronic music spawned its audio production techniques? Or is it vice versa?
The minimalist music concept existed long before the electronic music genre adopted its
characteristics, and electronic musicians are quite destined to explore audio signal processing, since that is the origin of their genre. But maybe it is also possible that the low complexity, stripped down, desolate musical environment of the minimalist genre made it extra fit for audio technical exploration? Perhaps, audio quality was given a space to shine as attention wandered off from the monotonous musical patterns?
1.5. Aim
This essay aims to investigate if and how audio signal processing and musical complexity are interrelated within minimalistic electronic music. To investigate this, both a literature review and a listening experiment were made. The literature review utilizes earlier research on perception in an attempt to explain the elaborate audio signal processing used in minimalistic electronic music. But it also investigates music production writings and music culture writings to see if minimalism in electronic music may be historically correlated to the evolution of audio technology.
The listening experiment has a more empirical approach, observing if audio signal processing actually may increase the perceived complexity of a rhythmical pattern, studying 12 human subjects. This experiment is meant to contribute some empirical grounds to the more theoretical approach of the literature review. Combined, the literature review and listening experiment are meant to give an increased understanding of how musical complexity and audio signal processing may be interrelated.
From reading this essay, an audio engineer working in music production might find ways to deal with music that has minimalistic properties. When an audio engineer is faced with a boring or uninteresting song, this essay may be helpful in understanding why the song is perceived as such.
Perhaps, this essay can also spawn ideas on how to make the song more interesting; Does the problem lie in mixing, or in the musical structure, or is it a combination of the two? The essay may also appeal to any musician or audio engineer who wishes to broaden their understanding of their respective professions from a perceptual point of view. Also, the literature review of the essay will be of interest to anyone who wants to deepen their knowledge about minimalistic electronic music.
1.6. Objective
A listening experiment will be conducted on 12 human subjects, observing if audio signal
processing increases the perceived musical complexity of a set of rhythmical music patterns. The listening experiment also investigates if the complexity of these rhythmical patterns is affected differently depending on whether the patterns musical complexity is high or low. To determine if the musical complexity of the rhythmical patterns actually can be categorized as low or high, a
complexity calculating computation method referred to as: Pressing's Cognitive Complexity Computation* (PCCC), will be used. Thus, the experiment will also show whether or not the PCCC-method can successfully approximate the musical complexity of rhythmical patterns.
A literature review of earlier research will act as a basis for the listening experiment. The literature review describes the perceptual, musicological, and audio technology-historical-aspects of
minimalistic electronic music, and how they may be interrelated.
1.7. Analysis Questions
To be able to analyze the results of the listening experiment, three sub-questions are posed. These three questions are;
Analysis A) Did subjects agree to the complexity categories determined by the PCCC- method?
Analysis B) Did the perceived complexity of the stimulus increase when signal processing was added?
Analysis C) Did signal processing affect perceived complexity of the stimulus differently within different complexity categories?
2. Literature Review
As has been brought up earlier, this literature review is on perceptual, musicological, and audio technology-historical-aspects of minimalistic electronic music. Here follows a brief explanation of the different literature areas that are reviewed.
• Perception.
A theory on how the human mind is thought to pick out information from patterns. More specifically in this case; patterns in musical audio streams.
• Musical Complexity.
A theory that tells of which types of musical patterns that are easy or hard for the mind to conceive of as actual patterns and not just random noise. This subject will be reviewed with the aim of understanding how minimalism may be perceived by the human mind.
• Electronic Music.
A genre of music that consists mainly of electronic instruments, including audio signal processing equipment used as a sort of instrument.
• Minimalistic Electronic Music.
A sub-genre within electronic music that utilizes highly continuous and repetitive musical patterns.
• The History of Audio Technology in Minimalistic Electronic Music.
Research on literature describing different minimalist electronic musicians use of audio technology.
Each of these three main topics (Cognition, Musicology and Audio Technology History) must be understood to be able to answer the research question. The topic of cognition is an important part of this knowledge, because it treats how we perceive the features of the other two topics. Therefore, it is perhaps best to start with discussing the perceptual aspect of the subject, to understand how our brain judges which sounds it needs to listen to, and which ones it can disregard.
2.1. Auditory Attention
Picture yourself having a conversation with a friend, while walking along the sidewalk of a street in the suburbs. What do you hear? There would be multiple sound sources around you; cars, birds, a construction site nearby, and of course the voices of you and your friend, conversing. Despite all of these sound sources, you would be able to focus on your friends voice. Having a conversation in this environment, would not be a problem. The concept of focusing on a specific sound in an auditory scene like this, is called auditory attention. There are almost always multiple sounds in a persons surroundings, some sounds might be of interest, and some might be disturbing. Sometimes, a sound that is not of interest at the moment, is louder than a sound that is of interest, yet we are able to focus on the interesting sound. (As in the example with suburban conversation, above) On the contrary, sometimes a sound that is of interest is louder than a sound that is not of interest, yet we are not able to focus on the interesting sound. Clearly, the foreground and background of an auditory scene (the auditory attention), is thus more complex to determine than just judging the loudness of individual sounds.
- Wrigley & Brown (2000)
2.2. Perception, Interpreting Patterns
If it is indeed not just how loud our friend talks that make us focus on him instead of the
background noise, then what is it about our friends voice that catches our attention? There are of course a number of acoustical factors like frequency-content that can be utilized to explain this, but there is also the aspect of perception playing a big part. Our cognitive perception of sound is
fundamentally based on patterns (Pressing, 1999), and as far as our brains are concerned, sound is a pattern of information that is received by our ears and interpreted in our minds. We can extract information from these sonic patterns, by interpreting them in our mind (Zanette, 2008) A pattern is a formation of something, that the human mind puzzles together, and makes sense of. All
information processed by the human mind is extracted from patterns, be it patterns of letters and words in a book, color patterns in a picture, or patterns of rhythms and melodies in music. But as in our example with the suburban conversation, above; our mind considers some patterns to be of higher relevancy than others.
It is believed that patterns with high consistency and repetitiveness, are easier for the human mind to puzzle together as a pattern. Less consistent patterns that contain a lot of change, are harder for the human mind to puzzle together as a pattern. How easy or hard it is for the mind to puzzle a pattern together is called; the complexity of a pattern. The easier a pattern is to puzzle together, the lower the complexity. The harder a pattern is to puzzle together, the higher the complexity. Low complexity patterns are consistent and repeat information, while high complexity patterns appear as more randomized and presents new information to the brain. A low complexity pattern tells the brain information that was already established earlier. We have already “learned” what the pattern means. Patterns of high complexity could be said to “make less sense” to the human mind, than patterns of low complexity. Though that does not at all mean that high complexity patterns are
“discarded” by our mind, it can explain why we where able to focus on our friend in the suburban conversation-example. The brain recognizes the pattern structure of our friend speaking with us, decodes the meaning of the words, and chooses that speech is more important to listen to than the background noise.
Speech is of course something that the human mind is very familiar with, and words
instantaneously mean something to us. The background noise from the suburb however, does not convey as much useful information as speech. Thus, our brain deems our friends words to be of higher importance than the background noise, and we are able to focus on the conversation.
- Zanette (2008)
- Madsen & Widmer (2006) - Pressing (1999)
2.3. Musical Complexity
Now, picture yourself in a concert hall. To the left of you, there is a violinist playing a melody, and to the right of you there is a flutist playing another melody. Would you focus your attention on the violinist or the flutist? This turns out to be a much harder question to answer than the suburban conversation-example, yet according to Madsen & Widmer (2006), musical complexity can be measured, by looking at the musical patterns. Musical patterns with high continuity will result in low complexity, while patterns with low continuity will result in high complexity. Madsen &
Widmer (2006), also conclude that if two voices are played simultaneously, the one of them that has the more complex musical pattern will most likely be considered as the interesting one. In our example with the duo in the concert hall, it could thus be derived from this theory that the musician playing the most complex musical pattern would win our attention, instead of the least musical pattern that makes more sense to us. It could even be said that low complexity musical patterns risk making so much sense that they bore us. Zanette (2008)'s research on musical complexity suggests that both repetitiveness and change are crucial for humans to create and understand the meaning of a music pattern, or literature. As Zanette (2008) points out:
In the search for a satisfactory combination of intelligibility and aesthetic substance, music conveys a subtle balance of reiteration and change, of redundancy and novelty, of recurrent shapes and fresh figures.
Different music genres balances repetition and change differently. But both are needed in order for the listener to perceive a musical structure and be able to extract information from it, according to Zanette. Music creating and listening, can be thought of as encoding and decoding information by using repetition and change as the rules for the code. It is not the repetition and change itself that constitute the information conveyed, they are simply the cognitive rules used to perceive a pattern.
An example that clarifies this can be read in Madsen & Widmer (2006), the essence of which is that:
pattern 1) abc abc abc and pattern 2) acb cba bac
consists of the exact same letters, and each letter occur the same amount of times, but the structure of the letters differ from pattern 1 to pattern 2. This means that the repetition and change (the complexity) are the same in both of the patterns, but due to their structure, they convey different information.
To be able to extract information from a piece of music, it is thus important to understand the structure that it was encoded with. In other words, to understand a certain type of music (for example minimalistic music), it helps to know what to listen for. An example of this would be the solos of Jazz Music. One part of the jazz song is called the “theme”, which is often structured as a
“normal” melody. Then, after the theme, a solo is introduced, in which of one of the musicians gets to improvise more or less freely over the chord-progression of the song. A listener who is familiar with jazz music will know what part of the song is the theme, and which part is the solo, which will help the listener to always stay on top of what is happening in the song. However, a listener who has never heard of jazz music might be confused by the sudden turn of the song, as the song looses its repetitive structure when the theme transcends into the solo part.
2.4. Minimalism In Electronic Music
Another interesting example of how musical complexity is employed in different genres is the genre that is in the scope of this essay; minimalism. In the 1960's, composers such as Steve Reich, Philip Glass, La Monte Young and Terry Riley had created a classical composing technique that centered around repetition and continuity, reducing the musical complexity to a minimum. Static, droning harmonies, and constantly repeating rhythmic patterns, slowly modulating throughout a musical framework devoid of solos, themes, refrains, and verses, was the core of minimalism composing in the '60s. These minimalist composers were deliberately trying to compose low complexity music, utilizing the very musical complexity theories that Madsen & Widmer, Zanette, and Pressing are discussing today. But it seems from much of the literature reviewed for this study, that as much as minimalism is about repetition and continuity, it is also about exploring the qualities of sound.
As Potter, (2012) describes it;
-Young's static harmonies, articulated with unchanging dynamics over long periods of time, set the agenda for a musical minimalism built on exploring the innards of sound.
[...] Reich and Glass [...] while continuing to activate their music with the crucial ingredient of repetition – or sustained sound, in the case of Young and other Americans such as Pauline Oliveros (b 1932) and Phill Niblock (b 1933) – have given greater prominence to melodic profile, timbral variety and sheer sonic allure.
The minimalism composing technique has lived on since the '60s, and keeping the fascination of sound in mind, it is perhaps not so strange that one of minimalism's heirs is the electronic music genre. Audio Culture: Readings in Modern Music (Cox & Warner, 2004), a book that is often cited in electronic music literature when defining genres, and in that context reviewed by Computer Music Journal as;
-About as good a solution as you might wish for”
(Whalley, 2005)
declares that minimalism in electronic music, such as the Techno-genre, owes its heritage from the classical minimalist composers in the 1960's, such as Steve Reich, Philip Glass, and Terry Riley.
In their book, Cox & Warner (2004) state that;
-Today, the cultural ties between minimalist composers and popular music have never been stronger, thanks largely to the influence of techno and its offshoots. […] Though composed for marimbas and bongos instead of samplers and sequencers, the kind of layered, modular repetition later fostered by Reich and Glass is the stuff of which Techno is made. Techno's minimalism recapitulates the sonic and social spirit of early minimalism, offering a repetitive, psychedelic provocation for mind-expansion and all- night partying. […] Minimal techno corkscrews into the very heart of repetition. Unlike dancehall, there are no “rewinds” in Techno: everything moves forward, but always maintaining the illusion of standing still.
(p.287, 288, 322.)
The word repetition seems to be a keyword in defining what minimalism is, not only to Cox &
Warner themselves, but also to Philip Sherburne, (2004) who was a co-writer in Cox & Warner's book;
-Detroit Techno pioneers like Derric May and Juan Atkins – emphasized a pared-down palette that cut away all the excesses of a bloating rock and pop tradition. Since then, much dance-floor fare has restrained itself to a limited set of sounds and has produced forms heavily reliant on loops, recurring sequences, and accumulation-through-
repetition. These are key tropes in much pop music, but electronic dance music particularly foregrounds the strategies pioneered in the work of so-called minimalist composers like Steve Reich and Philip Glass.
(p.319)
Later literature by Sicko & Brewster (2010) also implies that Techno is very much based on repetition, when describing the work of Minimal Techno-artists Robert Hood, and Daniel Bell;
-Hood's and Bell's sparse production styles have helped create one definition of
"minimalist" techno -the other coming from a style based on a reduction of the "song"
component to mere fractions of one bar. By cramming notes into smaller spaces, techno seems to become synonymous with repetition -one of the characteristics that generally turns people off from listening to dance music.
(p.141)
It is clear from the reasoning of Sherburne, Sicko & Brewster that minimalism in electronic music stems from the same repetitive and stripped down music structuring techniques that the minimalist composers in the '60s utilized, and that this composing technique coincides with the theories of how low complexity in musical patterns works. There is a consistent pattern to be found in literature on how the musical patterns are structured/arranged when composing minimalist electronic music. It is a very stripped-down musical arrangement-technique, in which the composer discards all excessive musical information, reducing the composition to an absolute minimum of musical components, or as more aesthetically put by Sicko & Brewster (2010), when describing minimalism within Techno;
-“There is also a strain of techno that survived by shedding characteristics rather than collecting them.”
(p.140)
These stripped-down, minimalistic, musical patterns are then wrapped and looped around a 4/4 kick drum and often an offbeat hi-hat, this constitutes the so called “beat”. The beat is however far from exclusive to minimalism within electronic music. Rather, the beat is constitutional for most
electronic dance music. Butler (2006) describes the importance of the beat within electronic dance music, in a passage about a live performance from Techno and House-DJ and producer Stacey Pulley;
-The common motif running through this cloth, however, is rhythm.
[…] The most obvious rhythmic force is the bass-drum beat: loud and insistent, it sounds out the same basic quarter-note pattern throughout most of the performance, and Pullen keeps it at a more or less constant tempo. In many ways, the beat is the music. Fans often describe the music simply as “beats” (as in, “let's go to the club and hear some beats”), and from this performance it is clear that the beat also defines the music as dance music.
[…] rhythm, therefore, is the raison d'être of electronic dance music.
(p.4)
The rhythmic patterns are repeated along the beat throughout the song, parts of it modulating in and out of the arrangement, rendering a musical result that differs greatly from, for
example, the climaxing arrangement-techniques of the Rock-genre.
-Where the traditional rock song is always invested in the logic of tension and release, build up, climax, and dénouement, minimalism has fostered a new interest in what philosophers Gilles Deleuze and Félix Guattari call the “plateau”, “a continuous, self- vibrating region of intensities whose development avoids any orientation toward a culmination point or external end.”
(Cox & Warner, 2004, p.288)
2.5. Music Examples of Minimalistic Electronic Music
• Jeff Mills – The Hacker.
Album: Waveform Transmission Vol. 1 (1992).
Label: Tresor.
• Plastikman – Consume.
Album: Consumed (1998).
Label: M_nus.
• Alexi Delano & Tony Rohr – Discoteca Butt.
Album: Sour Impressions (2008).
Label: Frankie Rec.
• Robert Hood – Minimal, Minimal.
Album: Omega: Alive (2011).
Label: M-Plant.
2.6. Minimalism and Perception
Earlier research on the human perception of musical patterns, has shown that music with low complexity is likely to receive less auditory attention than music with high complexity. (Madsen &
Widmer 2006) As has been discussed in this essay, minimalistic electronic music is characterized by highly continuous, stripped-down, repeating musical patterns, and could therefore be argued to have low musical complexity. It could be argued that earlier cognitive research implies that repetitive minimalistic electronic music risk to appear uninteresting to the listener, because of its inability to draw auditory attention. This coincides with implications already cited in this essay;
-By cramming notes into smaller spaces, techno seems to become synonymous with repetition -one of the characteristics that generally turns people off from listening to dance music.
(Sicko & Brewster, p.141)
Yet, musical minimalism has been around in popular culture since the 1960's, and is in its modern form (minimal techno, for instance) greatly appreciated on dance-floors all over the world. This suggests that the potential boredom inherent in the cognitive structures of minimalistic music may be overcome by some other aspect that actually interests the listener. Why and how can minimalism be interesting to the human mind? There are different explanations for the use of repetitiveness in minimalistic electronic music. Here follows a translated Swedish quote from Fredrik Johansson (2010), regarding Ambient-producer and composer Brian Eno,
-Eno wanted to create music that belonged to specific places. Music that was as easy to ignore, as it was interesting. He also wanted it to be divided into very long pieces, with little variation.
(p.54)
Johansson suggests that some minimalistic composers, like Brian Eno, use repetitiveness as a possibility for the listener to choose whether or not to focus their attention on the music. This implies that musical repetitiveness is only boring on a superficial level. Choosing to focus on repetitiveness, may reveal other interesting aspects of the music, rather than the music itself. This phenomenon seems to have been discovered by other artists than Eno;
-For artists such as Ryoji Ikeda and Carsten Nicolai, minimalist repetition provides a means of slowing down the data flow and focusing the listener's attention to the nature of sound and signal.
(Cox & Warner, (2004), P.287)
Sherburne (2004), on the other hand, suggests that there might be a more sociopolitical aspect of the purpose and effect of minimalism;
-One wonders if minimalism reflects a fundamental ambivalence about machine music.
Is the urge to pare things down to the absolute minimum born of some distrust of buttons and circuits? When machines can cram every nanosecond with noise, is the last refuge of humanity to be found in space, in restraint, and in silence?
(Sherbourne in Cox & Warner, 2004, p.326)
Sherburne brings a more contemporary analysis of minimalism, suggesting minimalism might be product of the contemporary music producers reaction to living in the fast lane of the modern world.
It is a viable thought, since readings in musicological literature on contemporary music production indicate that as of lately, minimalism has been a big trend in contemporary popular music culture.
As the possibilities of minimalism are explored by contemporary electronic musicians, minimalism has and may continue to influence contemporary music production greatly. In the same way that jazz went from being misunderstood as “boisterous dance music” to influencing all of the popular culture that came after it (Tucker & Jackson, 2012), minimalist electronic music may go from being considered as boisterous dance music to influencing all of the popular culture that is to come. It is perhaps only when one understands the concept of a music genre, that one can truly appreciate it.
It is perhaps only when one is immersed in the structural rules of minimalism, that one can listen beyond the boredom of repetition suggested by Madsen & Widmer, and move on to listening for the nature of sound and signal suggested by Cox & Warner.
Perhaps, most sounds are more complex then they seem at their first audition, and repetition gives the mind enough time to interpret increasingly complex patterns within the sound that are
overlooked at first.
Pressing (1999) concludes the following about the consequences of complexity for human behavior;
-When complexity overwhelms the system's capacity, performance breaks down by faltering, stopping, or by substitution of a simpler behavior that typically still retains some contextual fit. […] Adaptive practice reduces the likelihood of breakdown, and promotes rapid recovery to contextually apt behavior.
(p.7)
According to Pressing, if the complexity of a pattern exceeds our ability of puzzling it together fully, the mind will deconstruct the pattern into a simpler, but still contextually representative version of the pattern. When we have been exposed or trained sufficiently on the pattern at hand, we can handle the complexity better, and the mind puzzles the pattern together more correctly.
If one would think of the repeating musical patterns of minimalism, as a sort of constant training on interpreting a pattern, the following quote by Simon Reynolds seems to be not only an aesthetic description of minimal techno, but also an observation on the very same cognitive behavior that Pressing describes;
-What initially registers as merciless monotony reveals itself, on repeated plays, to be an inexhaustible forest of densely tangled breaks and multiple bass lines (the latter acting both as subliminal, ever-modulating melody and as sustained subaural pressure), relieved only by the sparest shadings of sampled jazz coloration.
(Reynolds, 1999, p.346)
2.7. Electronic Music and Audio Technology
It is quite self-explanatory that electronic music relies heavily on audio technology, which owes much to the advent of minimalism. When electronic music first arrived to the popular music scene in the form of such bands as Kraftwerk, they played sounds that had never been heard before.
This means that in a way, there was no pre-existing frame for early electronic musicians to adjust to.
Had electronic musicians played guitars instead, the audience would have had a reference of what a real guitar sounds like, and they might had been more reluctant to accept the quite dramatic way of audio signal processing that electronic music has fostered. But because of that the electronic musicians synthetic instruments did not originate from a natural acoustical environment, there has never been any limits to what electronic music may or may not sound like, because there was never any realism to reproduce. This lack of reference-point has enabled a relationship between the electronic musician and audio engineering equipment, in which (contrary to other music genres) the musician is often also the audio engineer.
-The origins of electronic music lie in the creative imagination. The technologies that are used to make electronic music are a realization of the human urge to originate, record and manipulate sound.
(Rincón, 2007, p.7)
Rincón implies that much of the electronic musicians creativity lay in the technology he uses, for technology is the electronic musicians instrument. The process of creating electronic music is not the traditional way of writing music for an instrument, but rather to “write” the actual sound, by generating and manipulating it with technology. Holmes (2002) means that the relationship between the electronic musician and audio technology is vital to understand, when discussing composition within electronic music;
-This requires an understanding of the technology that aids the composer, for in the field of electronic music the creative act is securely tethered to the equipment.
(Holmes. 2002, p.5)
When Holmes writes; “The technology that aids the composer”, this is not something exclusive to the electronic music genre. The tools of an artist is destined to in some way shape or guide the artists creative work, and therefore; the result of an artists work is to some extend dependent on the tools of the trade. A piano player, for instance, would probably not have written the same musical pieces, had he been working with the guitar instead of the piano. The tool (being the instrument), is coherent to the musical work. In the case of electronic music, the tools or instruments are those of audio technology. Thus, audio technology shape or guide the electronic musicians work, in the same way that the piano shapes or guides the pianists work, and the evolution of audio technology will to some extent be coherent with the musical evolution of electronic music.
This is quite evident throughout the history of electronic music, where the very first seed that would sprout the idea of the genre, is technological, and can be thought of as “the advent of recording”.
-The advent of recording had an effect not only on listening practices but also what sounds could be heard as music. Recording equipment allowed one to amplify and focus upon previously unheard or inconspicuous sounds. Moreover, as recorded entities, the sounds of trains or frogs, for example, could be placed on par with sounds made by violins or trumpets. From there, it was a short step to begin to perceive environmental sound aesthetically, radically transforming the nature of musical sound and
composition. “This blurring of the edges between music and environmental sounds,”
wrote R. Murray Schafer in 1973, “is the most striking feature of twentieth century music”.
(Cox & Warner 2004, p.66)
The importance of tape recordings to the birth of electronic music is noticeable in other literature as well. And the advent of cutting and splicing these tape recordings is often thought of as a vital influence to the electronic music genre. Tape recording was of course vital to most other music genres as well, since this enabled the recording and storing of sound as a whole.
But the importance of tape recordings to the electronic music genre did not lie mostly in the ability to store, but rather in the ability to alter. Holmes writes accordingly about composer Terry Riley;
-As we have noted, he was probably the first composer to experiment with extended tape delay and the accumulating effect of running a single loop of tape through several tape machines, recording and rerecording signals in real time during the course of a
performance. Riley came to his music of repeating figures and pulse rhythms largely by way of the tape recorder.
(Holmes. 2002, p.249)
One of the tape recorders unique feature as a musical instrument being its ability to cut, paste, and loop the same sound over and over again, Holmes implies that the repetitiveness of Rileys music originated from the usage of the tape recorder. It is however, not just repetitiveness that signifies electronic music. In a passage of The Producer As Composer (2005), producer and composer Brian Eno offers an extensive discussion on how audio technological progress has effected music in popular culture;
-If you listen to records from the '50s, you'll find that all the melodic information is mixed very loud -your first impression of the piece is of melody- and the rhythmic information is mixed rather quietly. The bass is indistinct, and the bass is only playing the root note of the chord in most cases, adding some resonance. As time goes on you'll find a spectrum, which was very wide, with vocals way up there and the bass way down there, beginning to compress, until at the beginning of funk it is very narrow, indeed.
Things are all about equally loud. Then, from the time of Sly and the Family Stone's
"Fresh" album, there's a flip over, where the rhythm instruments, particularly the drums and bass, suddenly become the most important instruments in the mix. A timbral change also takes place. The bass becomes a very defined instrument; by the use of amplitude control filters, the bass actually begins to take on a very vocal attack. The bass drum gains a more physical sound, and also has a click to it; generally you’ll find that bass drums are equalized very heavily. [The bass drum] becomes the loudest instrument in disco -watch the VU meter while a track is playing, and you'll see the needle peak each time the bass drum hits. (Eno, 50)
(Brian Eno, as cited in Moorefield, 2005, p.58)
This discussion describes a historical coherence in the progress of audio technology and the
evolution of popular music. In the '50s, audio technology was not yet advanced enough to provide a detailed representation of many instruments at once. There was not enough channels to be able to mix as many individual tracks as is available today. Sacrifices were inherent to the productions, and because of this, one had to carefully choose what was necessary to represent in the mix and what was not necessary. As Eno describes, the choice of priority was often singing and melodies. (Which would seem logical, taking in account the theories of musical complexity and auditory attention)
As multitrack recording developed, and bandwidth limitations within the audio technological
equipment decreased, producers and engineers were able to represent a greater detail to instruments, simultaneously. A wider frequency spectrum became available, and because of this the mix of instrumentation generally changed towards a greater emphasis on the drums.
In his book, Moorefield implies that the advancement of audio technological equipment made possible a greater audibility for a wider frequency spectrum, such as bass and treble. And as more and more hidden qualities of instruments became audible, this ultimately changed the musical composition and arrangement-techniques of popular music.
-Moreover, it was the introduction of the compressor, a device which detects peaks in a signal and reduces their levels in a controllable way, which made it possible to make the bass frequencies louder: engineers could now control the amplitude of the most dynamic instruments, the drum and the bass. The widespread changeover to amplified bass was another factor in this development, as was the introduction of the synthesizer with its extended frequency range.
(Moorefield, 2005, p.58, 59)
As discussed by Eno, earlier in Moorefield's book, the ability to enhance and control the drums and bass of mixes resulted in music genres like Disco, that often shares the typical characteristics of the drums (namely “the beat”) with techno and other electronic dance music. (Barrey & Gianni, 2003) Another common denominator for disco and electronic dance music is the DJ-culture (Brackett 2012), in which, according to Reynolds (1999), the use of audio technology represents more than just sound quality, because it also has a musical value;
-EQ-ing (boosting or lowering the frequency levels) can also be used to add extra dynamics to the experience. Djs are also increasingly using effects processors with functions like echo, phasing, and reverb, or deploying drum machines to add an extra tier of poly-rhythm, or programming mini-samplers to throw simple beat loops or riffs into the mix. ( p.281)
2.8. Discussion of Audio Technology's effect on Minimalism in Electronic Music
Taking in account the quotes from Holmes, Moorefield, and Eno, it can be concluded that audio technological progress has had an effect on electronic music production. This effect is known to have fostered minimalism (as in Holmes example with Terry Riley and the tape recorder), and it is also known to have fostered an emphasis on drums and bass (as in Enos' and Moorefields' examples about popular cultural music and the progress of audio technology.) From the definitions of
minimalistic electronic music, it can be concluded that the genre contains minimalistic, rhythmical patterns, with key focus on drums and bass. Thus, it is not too farfetched to draw a connection between minimalism within electronic music and the progress of audio technology.
Taking in account the literature on musical complexity within cognitive science, there is also reason to believe that repetition of an audio pattern changes the human minds interpretations of said
pattern. I.e; increasing repetition of a pattern also increases the amount possible interpretations of the pattern. Landy (2007) brings up a Pierre Schaeffers term “Acousmatic sounds”, that touches upon interpretation of repeated sounds;
-The term acousmatic was taken up again by Pierre Schaeffer and Jërôme Peignot to describe an experience […] consisting of hearing sounds with no visible cause on the radio, records, telephone, tape recorder etc. Acousmatic listening is the opposite of direct listening, which is the “natural” situation where sound sources are present and visible. . . By isolating the sound from the “audiovisual complex” to which it initially belonged, it creates favorable conditions for reduced listening which concentrates on the sound for its own sake, as sound object, independently of its causes or its
meaning. . . By repeated listening to the same recorded sound fragment, the emphasis is placed on variations of listening […] Indeed, if curiosity about causes remains in acousmatic listening (and it can even be aroused by the situation), the repetition of the recorded signal can perhaps “exhaust” this curiosity and little by little impose “the sound object as perception worthy of being listened to for itself”, revealing all its richness to us.
(p.78)
This theory of how the mind responds to repetition of audio patterns is supported by the more aesthetic observation made by Reynolds in the quotation made earlier in this essay;
What initially registers as merciless monotony reveals itself, on repeated plays, to be an inexhaustible forest.
This theory on perception may be one of the key reason to why genres like Minimal Techno exists, and how its history of audio technological dependency may be explained by cognitive science.
It may also explain why Robert Hood, in the intro of his track Minimal, Minimal, repeats the exact same spoken word sequence “minimal.”, non-stop for 30 seconds, before deploying a drum-pattern.
2.9. Conclusions
• Minimalist composers in music, whether they be classical or electronic musicians, are deliberately structuring their music with great amounts of repetition and continuity.
Minimalism is therefore deliberately characterized by low musical complexity.
• There is an ambiguity about how low complexity music is perceived, where some research indicate that it bores us, and some research indicate that it interests us.
• Many writers on musical minimalism suggests that minimalism is a musical way of immersing in the concept and qualities of sound through highly repetitive music structure.
• The evolution of minimalism in popular music (such as electronic music) is to some extent coherent with the evolution of audio technology.
• It is likely that audio technological advancements has induced minimalist approaches to popular music production.
3. Method
A listening experiment was used to observe if the perceived musical complexity increases when audio signal processing is added to a rhythmical music pattern. This was tested by using a
“modified MUSHRA-test”, in which 12 test subjects graded stimulus on how “prominent” or
“attention craving” they perceived them to be, on a scale from 0 – 100.
3.1. Prominence
Asking subjects to grade stimulus on “prominence” or “attention need” may seem odd, when it is really the “perceived musical complexity” that the experiment is intended to measure. The reason for not just asking the subjects to grade complexity, but instead disguising it as “prominent” or
“attention craving” is because;
1) It is time consuming and complicated to explain “complexity”, as can be seen in the works of Pressing (1999), Madsen & Widmer (2006) and Zanette (2008).
2) Moreover, if complexity was explained, that explanation might guide the subjects to grade complexity based on the theories discussed in this essay. And that might then generate a rather constructed result.
3) Finally, complexity is not only a cognitive-science-phenomenon, but also a musicological phenomenon. That way, grading “complexity” might had aided subjects who have
musicological knowledge to only grade the rhythmical complexity and overlook any audio signal processing.
Thus, subjects must grade complexity, without being biased by theories on how complexity works.
This is of course problematic, and in order for the subjects to understand what they are supposed to grade, complexity must be explained without spoiling that audio signal processing hypothetically might increase complexity. If subjects are in some way aware of this hypothesis, they may be guided to set scores that they otherwise would not. For this purpose, subjects were instead asked to grade how “prominent” or “attention craving” they perceived the stimulus to be. This choice of words derives from Madsen & Widmer (2006);
Continuity should lead to a low complexity rate and change will lead to a high
complexity value. A voice introducing new material will potentially become interesting to listen to. However if the new material is constantly repeated, we will pay less and less attention to it – become habituated or accustomed to the stimulus.
(p. 1)
The same theory is used in this experiment; a low complexity stimulus should receive less attention than a high complexity stimulus. Thus, the listener's attention to the stimulus reflects the listener's perceived complexity of the stimulus. For instance, the lead melody of a song is the melody that catches most of our attention. And as Madsen & Widmer (2006) showed, lead melodies and attention often comes with a high musical complexity. This makes the words “prominent” or
“attention craving” appropriate substitutes for “musical complexity”, in this experiment.
To further understand this choice of words, it is important to note that the word “prominent” is a translation of the Swedish word “påfallande”. The word “påfallande” describes to become aware of something. Something that stands out, and catches ones attention. For example, the phrase;
“Landskapet var påfallande vackert.”
“The landscape was påfallande beautiful.”
Would mean that the landscape was so beautiful that one gave extra thought to how beautiful it was.
3.2. Modified MUSHRA-test
The modification of the MUSHRA-test is that it was done without reference, anchor or explanatory words for the scoring. The program used for the test was the “STEP”-program, from ARL.
It is important to understand that this test is not a real “MUSHRA-test”. It is merely the MUSHRA- test interface that was used, because it has a convenient layout that suits the purpose of the test.
This interface gave subjects the opportunity to compare multiple stimulus of various complexity and audio signal processing against each other in each trial of the test. The test was configured so that in each trial, subjects compared two patterns from each complexity category, with two different signal processings applied. If the subject sets different grades for different signal processings within the same complexity category, then that would mean that complexity has been altered by the signal processing. It is in this way that the experiment is intended to answer the research question.
3.3. Procedure
When the subject came to the experiment, they were first asked to read a brief instruction that explained what the test was about, how to do it, and what the subjects task was. A translatipon of the instructions (which originally was in Swedish, and can be found in the Appendix) reads accordingly;
“About The test:
This test is a part of my C-essay, which treats how we perceive musical complexity. The purpose of the test is to find out what may affect the complexity of music, and this is done by You as a test subject listening and grading a number of rhythmical audio examples from how “attention craving” You perceive them to be. The audio examples will be played 6 at the time in a simple, interactive, computer program, that You control by clicking the example You want to listen to, compare the examples against each other, and grade them with a slider ranging from 0 – 100.
The test has two parts, Test A and Test B. Test A is a pre-test that has 3 trials, and Test B is the main test which has 5 trials.
What You Are Supposed To Grade
Your task is to grade to what extent you perceive that the audio examples catches your attention.
The most interesting example is to be given the highest score, and the least interesting is to be given the lowest score. But this does not mean that the “best” example is to be given high scores, and the
“worst” is to be given the low scores. For example; Tragic news are seldom pleasant, still they do get Your attention. Accordingly, You are supposed to grade how “prominent” or “ear-catching” the audio examples are.
Thank You For Participating!!”
After reading this, the subjects were free to ask any questions they had about the test. The test consisted of two parts, Test A and Test B. In Test A, the subject graded all patterns in the study, with no signal processing added, this was to see if the subject confirmed/agreed to the complexity
categories.* In Test B, the subject graded five trials with six patterns in each trial. The patterns in Test B are the same patterns as in Test A, but this time they have various degrees of audio signal processing added. Each trial contained two low complexity patterns, two of medium complexity, and two of high complexity. One of the patterns in the pairs always had a higher degree of audio signal processing than the other. This way, the subject compared both signal processing degrees and
complexity categories against each other, simultaneously. Both the order of the trials and the order of stimulus within the trials was randomized for each subject.
3.4. Stimuli
The stimulus were rhythmic patterns from three different complexity categories, and each pattern was processed with three different degrees of signal processing. An overview of all the stimulus can be seen in Figure 1.
Figure 1. Stimuli Chart
The different numbers represent each pattern, which on the Y-axis are divided into the three degrees of audio signal processing, and on the X-axis are divided into the three complexity categories. As can be seen in the chart, this makes for a total of 27 stimulus.
Each stimuli consisted of a one bar rhythm pattern, played with a single percussive sample (a
“pop”).* Before each rhythm pattern, there was a count-in-click. The patterns were created via MIDI**, not accentuated, and the timing of the patterns was exact MIDI-grid-timing. This was intended to minimize the risk of other musical features than just timing affecting the musical complexity of the patterns, enabling control over which features that made up the musical complexity of the stimulus.
3.4.1. Complexity Categories
As can be seen in Fiugre 1, each pattern belongs to one of three complexity groups;
• Low Complexity
• Medium Complexity
• High Complexity
There are three patterns in each of these three complexity-categories:
Low Complexity – Pattern 1, Pattern 2, Pattern 3.
Medium Complexity – Pattern 1, Pattern 2, Pattern 3.
High Complexity – Pattern 1, Pattern 2 Pattern 3.
To verify that these patterns actually can be argued to belong to these three categories, each pattern will be measured for a “complexity-value” using Pressing's Cognitive Complexity Computation
* Notation of the patterns can be seen in the Appendix. (10.1)
