From Instrument to Controller Benjamin O’Brien To cite this version: Benjamin O’Brien. From Instrument to Controller. 4ème Journée des Jeunes chercheurs du GREAM, Apr 2016, Strasbourg, France. hal-02177820 HAL Id: hal-02177820 https://hal.archives-ouvertes.fr/hal-02177820 Submitted on 9 Jul 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. FROM INSTRUMENT TO CONTROLLER Benjamin O’Brien, PhD Marseille, France http://benjamin-obrien.com 4ème Journée des Jeunes chercheurs du GREAM : « Instruments, instrumentalité et lutherie » RÉSUMÉ For example, listeners might become suspicious if they recognise and identify audio samples as triggered by plu- While the popularisation of analog effects in the 1960s cked strings. 1 In this case, is the electric guitar acting as changed the electric guitar sound, the application of digi- a musical instrument or a controller ? When considering tal signal processing techniques has transformed the ins- the latter scenario, what exactly does the electric guitar trument into a controller. Arguably, this shift transcends control and how ? If these questions cannot be adequa- the domains of hermeneutics and psychoacoustics. When tely answered, then the electric guitar may be considered faced with a new electric guitar sound, audiences might a mere prop for performance. brush it off as just another effect. However, it is the effect This paper examines the potential problems digitally itself that is the focus of their attention, which, in turn, mi- enhanced electric guitars pose in the context of musical nimises the electric guitar and its role as a sound produ- performance. The first part looks at how their use blurs cer. In a sense, the effect supersedes its source. This paper aesthetic considerations of content and form. The second discusses how advancements in digital music technology part discusses what constitutes electric guitar virtuosity in have changed the ways listeners engage with the electric the digital age. The paper concludes with thoughts on the guitar. instrument’s future in regards to a small, but emergent, trend of transforming acoustic instruments to sound like electronic versions of themselves. 1. INTRODUCTION Since its invention in 1931 [1], the electric guitar has 2. CONTENT & FORM undergone a transformation. Although the mechanics re- main largely intact, a transducer converts string vibrations Before considering how digital technology might af- into electronic impulses that are then amplified, its use fect a listener’s expectation and perception of an electric and sound have changed. Early on, jazz and pop musi- guitar, clear definitions of content and form are necessary. cians popularized its sound. For many, Jimi Hendrix’s per- In the context of a musical performance, the difference is formance of The Star Spangled Banner at Woodstock in an electric guitarist’s actions in time (form) articulate that 1969 forever changed the perspective of the electric gui- which is being performed (content). While abstract, these tar, as he conjured the sound images of "bombs bursting in definitions serve as a basis for questioning how identity air" with his expert control of the instrument and feedback relates to content, and control to form. [2]. Thereafter, modern guitarists were encouraged to ex- plore how different technology - guitars, effect pedals, and 2.1. Sound & Identity amplifiers - could change and develop their sound. And while most might not know the differences in circuitry A combination of techniques and technologies facili- that distinguish, for example, a Gibson SG from a Fender tates an electric guitarist’s exploration for desired sounds. Telecaster, many accept that these differences only affect Because of its design, the sonic possibilities of the electric sound quality. guitar are vast and (virtually) unrivalled. 2 Despite this po- Over the last decade, some musicians have been using tential, conventional techniques, such as plucking or strum- digital music technology to aid their creative practice. No- ming, and effects, such as reverb or distortion, have crea- wadays, electric guitarists can store, sequence, and pro- ted a standard class of electric guitar sounds. As Fred Frith cess sounds in real-time by using and developing MIDI programs and audio programming languages, such as Max/MSP 1 . For example, thinkplay has developed an audio application that, and SuperCollider [3][4]. They have in turn complicated among other things, does exactly this. A demonstration is available on YouTube [Accessed 7 March 2016] the relationship between the instrument and its role as a 2 . Although not designed for the sole purpose of making music, the sound producer. laptop computer is now arguably a more versatile musical instrument. //SynthDefinition to model Ibanez Tube Screamer //var amp_arg scales values [0.01, 1.0] to represent 'pre-gain' SynthDef(\tubeScreamer, {|out = 0, gate = 1, amp_arg = 0.01| First-Order High-Pass Amplification Clip Softly at Clip Hardly at input + output Filter (11.851 < gain < 0.48 Vpeak 2.5 Vpeak var sig, ts, env, amp_map; (Frequency cutoff: 118.234) sig = SoundIn.ar(0); 720.484 Hz) env = Linen.kr(gate, 0.1, 1, 0.1, 2); amp_map = ControlSpec(11.851, 118.234, \exp, 1.07); input First-Order Low-Pass Filter First-Order High-Pass output ts = RHPF.ar(sig, 720.484); (Frequency cutoff: 723.431 Hz) Shelving Filter ts = ts * amp_map.map(amp_map); //pre-gain ts = ts.softclip; ts = Mix.new([sig, ts]); ts = ts.clip; Figure 1. Ibanez Tube Screamer circuit schematic ts = RLPF.ar(ts, 723.431); sig = Limiter.ar(ts, 0.0)); Out.ar(out, sig * env); }).store; says, one way to "defeat the characteristics of the instru- ment as they presented themselves" [5], is to develop idio- Figure 2. SynthDef of Ibanez Tube Screamer written in syncratic techniques, and, if necessary, use technology to SuperCollider aid them. For some, technology is fundamental to the de- velopment of an electric guitarist’s sound, which, in many ways, is a metonym for their identity as a performer [6]. quence it, and thus their perspective of the electric guitar Rather than suggest a correlation between an electric gui- shifts from instrument to controller. tarist’s sound and their identity, one might consider the re- lationships between a sound’s characteristics and the tech- 2.2. Gesture & Control nology used to create the sound. First, how might digital technology be used to modify For some audience members, part of the dissonance electric guitar sounds to invoke other guitar sounds ? The comes from their lack of understanding the software used Boss AC-3 Acoustic Simulator, for example, transforms in conjunction with the electric guitar. Whereas a string the electric guitar into an acoustic guitar [7]. In this case, might be manipulated to make a sound, software mea- technology is being used to process electric guitar sounds sures input data to process and generate sound [10]. While to simulate acoustic guitar sounds. For some listeners, an some types of input data, such as frequency or ampli- interesting dissonance forms between what they hear and tude, could be discerned from informed audience mem- see. They hear strings vibrating over a resonating body, bers, most spectral analysis processing is less perceivable. but see that the electric guitar does not have one. These Thus, audiences are unable to decode whether the electric observations may lead them to reevaluate the criteria used guitarist’s gestures relate to instrumental manipulation or to distinguish an acoustic from an electric guitar. measurement. In addition to using technology to model the sounds of An interesting work that illustrates how an electric gui- other instruments, custom software can be written to re- tarist can use gesture to collapse distinctions between ma- create conventional effects. Given the circuit schematic of nipulation and measurement is Pat Metheny’s Orchestrion the Ibanez TS9 Tube Screamer Overdrive (Figure 1) [8], Project [11]. Metheny and a team of programmers and ins- one could program its design in SuperCollider (Figure 2). trument builders built a sophisticated system that allows The process of digitally implementing an analog effect re- the guitarist to control autonomous musical robots with veals a desire to create sounds that comport with existing his guitar. During performances, audiences hear and see electric guitar sound identities. Although reasons for this Metheny perform conventional jazz guitar music, but also are contingent on the electric guitarist, one might specu- sense he has some control over his robotic backing band. late that the presence and use of a computer, which has Thus, each gesture relates to both the making and measu- a capacity to do "anything," creates a need to reinforce ring of sound. Of course, this work is quite complex - and sounds associated with the electric guitar. extraordinary, which leaves some to consider the relation- So what happens when a computer is used to process ship between gesture and control in musical performance. and create sounds that are not directly associated with the There are many theories on musical gesture. David Mc- electric guitar ? For example, some electric guitarists use Neil defines ancillary gesture as "not directly involved cataRT, a concatenative sound synthesis 3 application de- in the production of sound" [12], whereas Claude Cadoz veloped at IRCAM [9], to create rich, fragmented sonic and Marcelo Wanderley write instrumental gesture is the textures that invoke the form of their playing, but retain "means of action on the physical world and a means of the qualities of the source recordings.