On the History and Aesthetics of Noise Reduction

Art Style | Art & Culture International Magazine On the History and Aesthetics of Noise Reduction Jens Schröter Abstract Modern sound production would and could not exist without different forms of noise reduction: Analog media technologies often used noise reduction filtering in different ways. A prominent example is of course the case of analog audio technologies, in which a variety of noise reduction technologies existed (Dolby A, B, C, SR, S; dbx; Highcom etc.). Firstly, the history of the most important of these systems will be media-archaeologically reconstructed. Noise reduction became necessary with the widespread use of analog audio tape technology, which has certain limitations. The focus will especially on the history of Dolby A, B and C since these were the most widely used systems. Their dominance blocked the way for technically better alternatives, especially Highcom. With the advent of digital technologies the discussed noise reduction systems became obsolete—the last commercial noise reduction system by Dolby: Dolby S couldn’t be established on the markets for tape decks anymore. Secondly, there is a genuine aesthetics of noise reduction: On the one hand, analog noise filtering produces artefacts— especially when reproducing noise reduced tapes in the wrong way or simply by the (sometimes incorrectly calibrated) noise reduction process (like, e.g. ‘hiss flags’ in dbx or a certain ‘muffled sound’ with Dolby). On the other hand, these effects are a rich source for experimental media aesthetics especially in electronic music, as can especially be seen in the work of Maurizio. A very important usage of noise reduction is the possibility to produce convincing silence—e. g., in cinema. This can be shown with outstanding clarity for the case of the movie A Quiet Place, in which—as its title already says—quietness plays an important role. ______ 85 ______ Art Style | Art & Culture International Magazine In Claude Shannon’s (and Warren Weaver’s) communication and information theory basal elements of a communication system are described (Fig. 1). It is emphasized that the channel is threatened by ‘noise’ at any time: During transmission, or at the receiving terminal, the signal may be perturbed by noise or distortion. Noise and distortion may be differentiated on the basis that distortion is a fixed operation applied to the signal, while noise involves statistical and unpredictable perturbations. Distortion can, in principle, be corrected by applying the inverse operation, while a perturbation due to noise cannot always be removed, since the signal does not always undergo the same change during transmission.1 Figure 1. Schematic of a communication system according to Shannon. Shannon, Claude. “Communication in the Presence of Noise”. In Proceeding of the IRE 37, no. 1, 11. 1949. Shannon discusses the need to remove as much of the interference that occurs in the channel—distortion and noise—as possible if the signal is to be transmitted with the best possible quality. Elsewhere he also discusses a ‘correction system’ (Fig. 2). Figure 2. ‘Correction system’ after Shannon, Claude Shannon, “A Mathematical Theory of Communication,” The Bell System Technical Journal 27 (1948): 409. ______ 86 ______ Art Style | Art & Culture International Magazine He relates this to a ‘discrete channel’, which does not have the characteristics of the analog sound reproduction systems that will be the focus here—but we will encounter this principle again in a similar form. The ‘correction system’ works like this: An ‘observer’, which of course can be an “auxiliary device”2 (but sometimes is also a skilled sound engineer), taps the signal M from the transmitter and compares it with the signal M’ received. The difference between the two is due to the interference of the channel. So the observer generates ‘correction data’ and forwards it to a ‘correcting device’, which transforms the signal M’ so that it again corresponds to the original signal M (or at least comes as close to it as possible). Without going further into Shannon’s difficult theory here, this scheme of ‘correction devices’ points to upcoming methods of noise suppression—the filtering out of the “thermal noise that all matter—and therefore also resistors or transistors—radiates when operating (according to another one of Boltzmann’s formulas) …”3 To remain in our example: If it would be possible to successfully add the noise of the channel phase-inverted to the signal M’, it would disappear. Also in this sense, “messages themselves can be generated as … filterings of noise.”4 But this does not have to be the case: Artfully applied filters, e.g., to alienate acoustic or visual signals, serve exactly the opposite purpose of distancing from an original signal, however given, and make the technicality of the channel visible—to the extent that the underlying channel (in its institutional forms) can even give its name to the filters, as on Instagram, for example. This essay focuses on a particular group of media technologies, their history, associated practices and aesthetics, at least sketchily: Analog sound recording on tapes (tape, compact cassette). As one can infer from Shannon’s general theory of communication, ‘noise’ is a problem for any channel, not just a particular type of channel. The concentration on analog tape recording of audio signals can be explained—apart from the inevitable need to focus on something—simply by the fact that analog audio technology made the concept of ‘noise reduction’ and the filtering methods associated with it, especially such as ‘Dolby’, known for at least a certain time; the Dolby logo (Fig. 3) is, or rather was, widely known.5 ______ 87 ______ Art Style | Art & Culture International Magazine Figure 3. The Dolby logo (January 18, 2020). On the basis of the technical operations certain cultures, practices and aesthetics of noise filtering developed, which can be described at least in excerpts. Eventually one could get first hints on the connection of theories, technologies and practices like the aesthetics of filtering. It is not possible to go into detail here about the history of the tape technology and the subsequent development of the compact cassette as a commercial technology.6 It can be stated that audio tapes, which are to be magnetized, as sound storage media pose special challenges with regard to the channel. Thus, in 1940, it was stated laconically: “The reproduction of magnetic sound recordings on steel wire and steel tape, but also on magnetizable film, is, according to the present state of the art, afflicted with a disturbing background noise.”7 On the one hand, they cannot be recorded at arbitrarily high levels, because then there is a risk of distortion. On the other hand, this means that the signal is not very ‘loud’ compared to the white noise of the tape. Early developments such as premagnetization—later dynamized in ‘Dolby HX Pro’ depending on the proportion of high frequencies in the audio signal8—allowed a significant improvement in level control, but still left a hefty noise.9 An early idea to reduce noise (which was also used in broadcasting) is ‘pre-emphasis.’ The idea: Since noise is especially disturbing in the range of higher frequencies, one raises high frequencies before the recording, with an appropriate circuit, and lowers them again during playback—so one also reduces the noise.10 The big problem with this is that the high frequencies become louder during recording and the saturation of the tape is reached more quickly, i.e., distortion is created. This in turn means that you have to lower the recording level as a whole, which then leads to a lower signal-tonoise ratio in other frequency ranges. ______ 88 ______ Art Style | Art & Culture International Magazine In addition, the quality of the signal reproduction depends decisively on the tape speed. The faster the tape runs, the higher the frequency range and signal-tonoise ratio. For this reason, many classic tape machines had comparatively high tape speeds of 38.1 or even 76.2 cm/s.11 So, in order to make the channel as noise-free as possible, it would be advisable to use the highest possible tape speed. But obviously, this introduces a new problem: The faster the tape runs, the less the running time of a given reel. If one wanted to reproduce a longer concert, one would have to use very large reels, which make the device bulky and unwieldy and, moreover, create mechanical problems with the acceleration and deceleration of the large, sluggish reels. Making the tape thinner is also a limited option—after all, it must not break. The problem becomes even more acute when trying to establish tape technology as a handy commercial technology in the form of the compact cassette. The small—i.e., ‘compact’—cassettes do not fit as much tape, but the vinyl records established at that time had an average running time of about 40–45 minutes. So, cassettes were developed that could hold either 90 minutes (45 minutes per side = a whole record) or 60 minutes (30 minutes per side = one side of a record). However, because so little tape fit into the cassette, the tape speed then had to be greatly reduced—to 4.76 cm/s for the compact cassette. This significantly reduced headroom and signal-to-noise ratio—even taking into account that the compact cassette was intended more for a market that was concerned with recording the less dynamic, popular music.12 Add to that the fact that the tape was quite narrow compared to tape on tape reels,13 again at the expense of headroom. In short, the quality was weak. In order to establish the compact cassette as a popular medium, improving its sound quality and, above all, lowering the noise level was certainly desirable.14 The trade-off between the economics of tape length (which included its commercial fit into an existing media ensemble) and quality motivated the development of noise filters. Even the much better and often more expensive tape recorders still produced considerable noise at economically reasonable lower speeds: “The continuing demand for improvement in quality delivered to the consumer makes further evolution in noise-reduction systems mandatory.”15 This is also a complicated story that has not been presented anywhere as far as I can see. I can only go into one, but still the most famous, case here: Dolby.16 Ray Dolby founded Dolby Industries in 1965 and soon developed his first noise reduction system, the professional Dolby A. Sound studios in particular needed noise reduction methods, because multitrack recordings are used especially in the production of popular music. However, with each track—especially since each track must be narrower to fit on the tape—more noise is added, so that either a ______ 89 ______ Art Style | Art & Culture International Magazine further increase in tape speed comes into question, which soon reaches both economic and mechanical limits, or noise reduction. In 1967, a paper appeared in which Dolby outlined his process. The basic principle is that, as with other ‘companders’ (of ‘compressors’ and ‘expanders’), only in many ways more cleverly realized, the signal is separated into frequency bands by a system of filters before recording. These are treated separately, with the quiet parts being boosted during recording and lowered again during playback—and with them the noise: Low level signal components are amplified in four independent frequency bands prior to recording/sending, which is accomplished by adding the outputs of four filter and low-level compressor channels to the main signal. During reproduction, the filter and compressor network is connected in a complementary way. Low-level components are subtracted from the incoming signal, and noise acquired in the audio channel is thereby subtracted or reduced as well.17 Figure 4. Simplified illustration of the operation of the Dolby compander, Heinrich Sauer, “Immer mit der Ruhe,” Stereoplay 11 (1982): 42. ______ 90 ______ Art Style | Art & Culture International Magazine Dolby’s development had a number of merits, so that already in 1970 it could be stated that “there are no technical arguments or quality compromises that could speak against its general use. It is therefore also to this day the only compander process that has found its way on a larger scale into commercial music production for record and radio throughout the world.”18 Soon a slimmed-down process was introduced: Dolby B. It no longer worked with four different frequency bands and only in the high frequency range, where noise was most distracting. It was to be found in practically every consumer tape deck from the second half of the 1970s at the latest.19 It has been noted about this process that it “keeps circuitry costs down and is ultimately good for the wallet.”20 The technology is a “compromise between engineers and marketing experts.”21 Figure 5. Commercial music cassette “Tomorrow Santa Claus is Coming” with Dolby logo (January 18, 2020). In any case, Dolby A largely prevailed in the professional sector and Dolby B in the consumer sector, Dolby B also in commercial music cassettes (Fig. 5)22—also because cassettes recorded with Dolby B could be played in still acceptable quality on devices without Dolby expanders (an important backward compatibility). This entry of the music industry, as well as tape deck manufacturers into Dolby, which would require its own historical representation, created a path dependency that made it very difficult for competing systems. ______ 91 ______ Art Style | Art & Culture International Magazine A system that was used at least in some tape decks (for example by Technics, the author of this text was a long-time owner of a Technics tape deck RS-B905 with Dolby B, C and dbx) and increasingly also in the studio area was dbx. It produced—since it companded the whole frequency range unlike Dolby B—a larger signal-to-noise ratio, however the tapes compressed in such a way could not be played back well without dbx and dbx produced easily artifacts like socalled ‘breathing’, i.e. an audibly louder and softer becoming noise around signal peaks above all in the high tone range. 23 From the mid-1970s, Telefunken developed a very good and advanced compander system, HighCom, which was clearly superior to Dolby B,24 but was no longer able to establish itself due to the path dependency—especially since Dolby introduced a better commercial compander, at least compared to Dolby B, with Dolby C as early as 1980.25 In 1986, Dolby Labs introduced Dolby SR, the successor to Dolby A for the professional sector, which is considered the crowning achievement in the history of analog audio companders.26 From Dolby SR there was—similar to Dolby A to Dolby B—again a simplified procedure for the consumer sector, Dolby S, which was implemented for the first time in 1990 on commercial tape decks (and where care was taken to ensure that tapes compressed in this way could also be played back to some extent with Dolby B). But at that time the CD had already been established and especially the possibilities to copy CDs with computers had grown. The analog tape deck technology gradually disappeared, so that Dolby S was denied the big breakthrough. The spread of especially Dolby B and other noise reduction methods was also accompanied by some specific practices and aesthetics,27 which will be briefly discussed below and, as it were, autoethnographically based on my years of tinkering with tape decks. There was the principal problem that the whole principle of the compander presupposes a symmetry between compression and expansion: Only when all these control processes are exactly mirror images of each other during recording and playback can the original signal be heard again with an intact frequency and phase response, transient response and correct dynamics. This is not a problem in theory. But in practice. Tape devices always bring their own individual frequency response, head mirror resonances and treble drop make the compander believe something different during playback than the compander entrusted to the tape during recording.28 ______ 92 ______ Art Style | Art & Culture International Magazine Tapes often sounded muffled, so it was better to play them back without the Dolby noise filter, which made them more noisy but sounded clearer. Another trick was to cleverly mask the notches on the top of the cassette, so that a CrO2 tape cassette, for example, was played back as a Fe2O3 tape cassette, which also raised the treble—and thus made it possible to use the Dolby noise reduction without dullness. In general, all companders require very precise calibration procedures; already during recording it is recommended to measure the individual tape exactly manually or with the help of a measuring computer (if available), which was only possible on higher-quality tape decks.29 In the process, the calibration required for good quality companding is also compromised over time: Over the years, tapes may lose magnetization, affecting proper noise filtering; but it may also be that no or no correctly working devices can be found for playback. This is where the problem of archiving arises—in addition to tapes, equipment must also be archived. So, a small connoisseur scene has formed around the question of how to play back and restore old tapes correctly and what problems can arise in the process, a ‘Culture of Noise Reduction’ if you will.30 At the same time, these difficulties also mean that one can hear—at least with some experience—when music is reproduced incorrectly. The music then sounds dull or sharp, pumping, breathing, reverberating or distorted. In such disturbances the filter system, which should make the channel as inaudible as possible, itself becomes audible and possibly the connoisseur can even hear which noise reduction was used. Nevertheless, this typically analog sound disturbances can itself become the source of an aesthetics. The early cassette culture, often associated with experimental or ‘underground’ music, was accompanied by a corresponding sound, often associated with involuntarily or unconsciously false companding practices (which could also operate as an opposition to the high-quality ‘high fidelity’ perceived as bourgeois31). Even under digital conditions and a nostalgic desire for the analog32 associated with them, the dull, the breathing, and the lace itself can become aesthetic forms - for example, in electronic dancefloor music. For example, “M Ø6B” by Maurizio cites overtly misrepresented tapes that are highly noisy, while “M07A” follows the aesthetic of the dull.33 In the track “Don’t” by Actress (on the album “Ghettoville”) you hear a sample at the beginning and in the short pause after that the noise level turns up like a Dynamic Noise limiter gone crazy, or a badly calibrated dbx tape played back without dbx.34 ______ 93 ______ Art Style | Art & Culture International Magazine But perhaps the most important aesthetic contribution of noise reduction as a technology of silence is that silence can be produced. Phases of silence as a dramaturgical tool, die Ruhe vor dem Sturm, are only possible if silence is not obstructed by hiss. A brilliant example for this strategy is the 2018 movie A Quiet Place (John Krasinski). The original plot is that earth is invaded by a hostile alien species that killed most of humanity. The species is blind—but they have very good ears. The remaining humans can only survive if they behave very, very quiet—if you make one noise then the monstrous aliens can locate you, come and kill you. The film is centered on a family that tries to survive. Most of the film is very quiet—the slightest noises, for example like dry leaves crackling under the feet, are thereby amplified in a haunting way. Noises that are normally completely overheard in real life and in the movies are blown up to an existential dimension. Every object that could produce a sound becomes an ominous threat. This is even more radicalized by the figure of the daughter. When scenes are shown from her point-of-audition there is an absolute, oppressive silence. Since we heard through her, non-functional, ears, it is unclear if she or someone else made a dangerous noise. This brilliant and terrorizing aesthetics of silence is only possible if you don’t hear hiss all the time. The silence produced by noise reduction is not just an absence of sound—it is an aesthetic element in its own right. Author Biography Jens Schröter, Prof. Dr., is chair for media studies at the University of Bonn since 2015. Since 4/2018 director (together with Anja Stöffler, Mainz) of the DFG-research project “Van Gogh TV. Critical Edition, Multimedia-documentation and analysis of their Estate” (3 years). Since 10/2018 speaker of the research project (VW foundation; together with Prof. Dr. Gabriele Gramelsberger; Dr. Stefan Meretz; Dr. Hanno Pahl and Dr. Manuel ScholzWäckerle) “Society after Money – A Simulation” (4 years). Director (together with Prof. Dr. Anna Echterhölter; PD Dr. Sudmann and Prof. Dr. Alexander Waibel) of the VW-Main Grant “How is Artificial Intelligence Changing Science?” (Start: 1.8.2022, 4 Years); April/May 2014: “John von Neumann”-fellowship at the University of Szeged, Hungary. September 2014: Guest Professor, Guangdong University of Foreign Studies, Guangzhou, People’s Republic of China. Winter 2014/15: Senior-fellowship at the research group „Media Cultures of Computer Simulation.” Summer 2017: Senior-fellowship IFK Vienna, Austria. Winter 2018: Senior-fellowship IKKM Weimar. Winter 2021/22: Fellowship, Center of Advanced Internet Studies. Recent publications: Medien und Ökonomie, Wiesbaden: Springer 2019; (together with Christoph Ernst): Media Futures. Theory and Aesthetics, Basingstoke: Palgrave 2021. Visit www.medienkulturwissenschaft-bonn.de / www.theorieder-medien.de / www.fanhsiu-kadesch.de ______ 94 ______ Art Style | Art & Culture International Magazine Notes 1. Claude Shannon, “Communication in the Presence of Noise,” in Proceeding of the IRE 37, no. 1, 11. 1949. 2. Claude Shannon, “A Mathematical Theory of Communication,” The Bell System Technical Journal 27, no. 3 (1948): 408. 3. Friedrich Kittler, “Signal-to-Noise Ratio,” In The Truth of the Technological World: Essays on the Genealogy of Presence, ed. idem, trans. Erik Butler (Palo Alto: Stanford University Press, 2014), 167. Kittler refers in the following with Shannon to a further point, namely that the noise could also be a carefully encoded message and is relevant for the further military use of communication theory (and incidentally also for the question of extraterrestrial communication), but I will skip this here. 4. Kittler, “Signal-to-Noise Ratio,” 169. 5. What is not discussed in detail here is the role of Dolby technologies for cinema, see Gianluca Sergi, The Dolby Era. Film Sound in Contemporary Hollywood (Manchester: Manchester University Press, 2004). I will also not go into the technologies of ‘Active Noise Cancellation’, which currently play a major role in headphones, see Jens Schröter, “Technologies of Silence.” In Techniques of Hearing: History, Theory and Practices, edited by Michael Schillmeier, Robert Stock und Beate Ochsner 21–35 (New York: Routledge 2022). 6. Cf. Pia Fruth, Record. Play. Stop. Die Ära der Kompaktkassette: Eine medienkulturelle Betrachtung (Bielefeld: transkript-Verlag, 2018) and Axel Volmar and Judith Willkomm, “Klangmedien,” in Handbuch Medienwissenschatf, ed. Jens Schröter (Stuttgart: J.B. Metzler, 2014). 7. Hans-Joachim von Braunmühl and Walter Weber, Verfahren zur magnetischen Schallaufzeichnung, Reichspatentamt Patentschrift Nr. 743 411, Klasse 42g, Gruppe 10 02, filed June 28, 1940 and issued November 4, 1943. Translation by the author. 8. Cf. Ian Hardcastle, “Quality Improvements in Pre-Recorded Cassettes,” SAE Transactions 95 (1986): 1622–1629. 9. Cf. Braunmühl, and Weber, “Verfahren zur magnetischen Schallaufzeichnung” esp. 2ff. 10. Interestingly, the first CD standard also included a pre-emphasis for CDs, but this was hardly used in practice. 11. Cf. “Tonbandtechnik,” Genesis-Audioline accessed January 17, 2020, genesisaudioline.de/technik/tonbandtechnik/: “You may wonder how the ‘crooked’ values for tape speeds came about: they were created by halving the next highest speed in each case (the number of tracks is also gained by progressive halving, after all). At the beginning of tape technology there was a venerable 76.2 cm/sec, which corresponds to 30 inches per second. Ultimately, in fact, the gradation is based on the British-American system of measurement, and in order not to complicate international tape exchange, it was left at that and values from the metric system were dispensed with (38.1 cm/sec = 15″/sec; 19.5 cm/sec = 7.5″/sec; 9.53 cm/sec = 3.3/4″/sec, (″ is the abbreviation for inches)”, translation by the author. ______ 95 ______ Art Style | Art & Culture International Magazine 12. It cannot be surprising that the formats of the distribution media tend to determine not only dynamics but also, for example, length of popular music pieces, cf. Theodor W. Adorno (signed “Hektor Rottweiler”), “The Form of the Phonograph Record,” October 55 (1990): 57f: “The only thing that can characterize gramophone music is the inevitable brevity dictated by the size of the vinyl plate.” 13. 3.81 mm compared to 6.35 mm of the narrowest tape. 14. See the notes on the “Phillips Dynamic Noise Limiter” in Anonymous, “London Audio Fair. Review of a Show Attended by more than 70,000,” Wireless World 77 (December 1971): 585/586. 15. David E. Blackmer, “A Wide Dynamic Range Noise-Reduction System,” DB: The Sound Engineering Magazine 6 (1972): 54. However, the quote is from a text that is already about a critical reaction to the Dolby system. 16. See on Dolby’s method fundamentally: O. Diciol, “Dolby-System. Technik zur Verbesserung des Störspannungsabstands,” Hifi-Stereophonie 11 (1972). The method is very well described in Heinrich Sauer, “Immer mit der Ruhe,” Stereoplay 11 (1982). 17. Ray Dolby, “An Audio Noise Reduction System,” Journal of the Audio Engineering Society 15, no. 4 (1967): 388. See also Ray Dolby, “Audio Noise Reduction – Some Practical Aspects,” Audio 52, no. 6 (1968a) and idem, “Audio Noise Reduction. Part 2 (Conclusion),” Audio 52, no 7 (1968b). 18. K. Bertram, “Dynamikverbesserung mit dem Dolby-stretcher,” Fernseh- und Kinotechnik 4 (1970): 123. Translation by the author. 19. Cf. Dolby, Ray. “A Noise Reduction System for Consumer Tape Recording,” in 2nd Audio Engineering Society Convention. 16–18 March 1971. 20 Sauer, “Immer mit der Ruhe,” 43. Translation by the author. 21. Friedrich Kittler, “Gleichschaltungen. Über Normen und Standards der elektronischen Kommunikation,” in Geschichte der Medien, ed. Manfred Faßler, and Wulf Halbach (Munich: Fink, 1998), 261. Translation by the author. 22. And even with the audio tracks of videotapes. 23. For dbx, see Blackmer, “A Wide Dynamic Range.” 24. Cf. Jürgen Wermuth, “Dynamik-Erweiterung durch neuartigen Studio-Kompander,” Funkschau 47, no. 18 (1975) and Gerhard Dickopp, and Ernst Schröder, “Der Telefunken-Kompander,” Rundfunktechnische Mitteilungen 22, no 2 (1978). One of many other alternative, ultimately failed approaches is, for example, the Burwen Laboratories Noise Eliminator, see Richard S. Burwen, “Design of a Noise Eliminator System,” Journal of the Audio Engineering Society 19, no. 11 (1971). Cf. Michael G. Duncan, Davud Rosenberg, Graham W. Hoffman, “Design Criteria of a Universal Compandor for the Elimination of Audible Noise in Tape, Disc, and Broadcast Systems,” Journal of the Audio Engineering Society 23, no. 8 (1975). This text uses computer simulations to design criteria for an ideal compandor (the spelling ‘compandor’, also common in Dolby’s early texts, did not prevail) and measures Dolby, dbx, and the Burwen Laboratories Noise Eliminator against them. None of the systems meets the criteria, the ideal compander does not seem to have been realized, although it would be worth checking whether Telefunken would do better here with Telcom and then HighCom. ______ 96 ______ Art Style | Art & Culture International Magazine 25. On Dolby C see, among others, Hardcastle, “Quality Improvement,” 629ff and Ray Dolby, “A 20 dB Noise Reduction System for Consumer Applications,” Journal of the Audio Engineering Society 31, no. 3 (1983). 26. Cf. Karl M. Slavik, and Stefan Weinzierl, “Wiedergabeverfahren,” in Handbuch der Audiotechnik, ed. Stefan Weinzierl (Berlin: Springer-Verlag, 2008): 621–622. 27. We cannot and should not go into the interesting discussions about an aesthetics of noise in literature, for example, see Rüdiger Campe, “The ‘Rauschen’ of the Waves. On the Margins of Literature,” SubStance 61 (1990). 28. Sauer, “Immer mit der Ruhe,” 43. Translation by the author. 29. The most expensive and best tape decks at the time, the Nakamichi Dragon and the Revox B-215, were in various ways technologies for calibration fetishists. The history of these extraordinary media technologies remains to be written. 30. Cf. “Noise Reduction,” Richard L Hess–Audio Tape Restoration Tips & Notes, accessed January 18, 2020, richardhess.com/notes/formats/magnetic-media/magnetictapes/analog-audio/noise-reduction. Apparently there are no digital emulations of the playback side of companders yet, which would facilitate the playback of old tapes and offer greatly expanded calibration possibilities: “The question of noise reduction companders comes up often on discussion boards. I am unaware of any noise reduction (NR) plugins to decode analog signals, it would be a logical item to create.” 31. Cf. Fruth, Record. Play. Stop. 32. Cf. Dominik Schrey, Analog Nostalgie in der digitalen Medienkultur (Berlin: Kulturverlag Kadmos, 2017). Not only the vinyl record, but even the tape deck are making a comeback today – albeit on a modest scale. Let’s see when there will be a Dolby nostalgia …. 33. Both on: “Maurizio – M-Series,” Discogs, accessed January 18, 2020, www.discogs.com/de/Maurizio-M-Series/release/203360. 34. See generally on glitches in electronic music, though without direct reference to noise reduction, Mark Fisher, “The Metaphysics of Crackle. Afrofuturism and Hauntology,” Dancecult: Journal of Electronic Dance Music Culture 5, no. 2 (2013). ______ 97 ______ Art Style | Art & Culture International Magazine Bibliography Adorno, Theodor W. (signed “Hektor Rottweiler”), and Thomas Y. Levin. “The Form of the Phonograph Record.” October 55 (1990): 56–61. Anonymous, “London Audio Fair. Review of a Show Attended by more than 70,000.” Wireless World 77 (December 1971): 585–587. Bertram, K.: “Dynamikverbesserung mit dem Dolby-stretcher.” Fernseh- und Kinotechnik 4 (1970): 123–126. Blackmer, David E.. “A Wide Dynamic Range Noise-Reduction System.” DB: The Sound Engineering Magazine 6 (1972): 54–56. Von Braunmühl, Hans-Joachim, and Walter Weber. Verfahren zur magnetischen Schallaufzeichnung. Reichspatentamt Patentschrift Nr. 743 411, Klasse 42g, Gruppe 10 02, filed June 28, 1940 and issued November 4, 1943. Burwen, Richard S.. “Design of a Noise Eliminator System.” Journal of the Audio Engineering Society 19, no. 11 (December 1971): 906–911. Campe, Rüdiger. “The ‘Rauschen’ of the Waves. On the Margins of Literature.” SubStance 61 (1990): 21–38. Diciol, O.. “Dolby-System. Technik zur Verbesserung des Störspannungsabstands.” Hifi-Stereophonie 11 (1972): 1152–1161. Dickopp, Gerhard and Ernst Schröder. “Der Telefunken-Kompander.” Rundfunktechnische Mitteilungen 22, no. 2 (1978): 63–74. Discogs. “Maurizio – M-Series.” Accessed January 18, 2020. www.discogs.com/de/Maurizio-M-Series/release/203360. Dolby, Ray. “An Audio Noise Reduction System.” Journal of the Audio Engineering Society, 15, no. 4 (October 1967): 383–388. Dolby, Ray. “Audio Noise Reduction – Some Practical Aspects.” Audio 52, no. 6 (1968a): 19–22. Dolby, Ray: “Audio Noise Reduction. Part 2 (Conclusion).”Audio 52, no. 7 (1968b): 26–30. Dolby, Ray. “A Noise Reduction System for Consumer Tape Recording”. In 2nd Audio Engineering Society Convention , (Cologne/Germany, 16–18 March 1971). Dolby, Ray. “A 20 dB Noise Reduction System for Consumer Applications.” Journal of the Audio Engineering Society 31, no. 3 (1983): 98–113. Duncan, Michael G., Davud Rosenberg, and Graham W. Hoffman. “Design Criteria of a Universal Compandor for the Elimination of Audible Noise in Tape, Disc, and Broadcast Systems.” Journal of the Audio Engineering Society 23, no. 8 (1975): 610–622. Fisher, Mark. “The Metaphysics of Crackle. Afrofuturism and Hauntology.” Dancecult: Journal of Electronic Dance Music Culture 5, no. 2 (2013): 42–55. Fruth, Pia. Record. Play. Stop. Die Ära der Kompaktkassette: Eine medienkulturelle Betrachtung. Bielefeld: transcript-Verlag, 2018. Genesis-Audioline. “Tontechnik.” Accessed January 17, 2020. genesisaudioline.de/technik/tonbandtechnik/. ______ 98 ______ Art Style | Art & Culture International Magazine Hardcastle, Ian. “Quality Improvements in Pre-Recorded Cassettes.” SAE Transactions 95 (1986): 622–637. Hess, Richard L. Audio Tape Restoration Tips & Notes. “Noise Reduction.” Accessed January 18, 2020. richardhess.com/notes/formats/magnetic-media/magnetictapes/analog-audio/noise-reduction. Kittler, Friedrich. “Gleichschaltungen. Über Normen und Standards der elektronischen Kommunikation.” In Geschichte der Medien, edited by Manfred Faßler, and Wulf Halbach, 255–268. Munich: Fink,1998. Kittler, Friedrich. “Signal-to-Noise Ratio.” In The Truth of the Technological World: Essays on the Genealogy of Presence, edited by idem and translated by Erik Butler, 165–177. Palo Alto: Stanford University Press, 2014. Sauer, Heinrich. “Immer mit der Ruhe.” Stereoplay 11 (1982): 42–45. Schrey, Dominik. Analoge Nostalgie in der digitalen Medienkultur. Berlin: Kulturverlag Kadmos, 2017. Schröter, Jens. “Technologies of Silence.“ In Techniques of Hearing: History, Theory and Practices, edited by Michael Schillmeier, Robert Stock und Beate Ochsner 21–35. New York: Routledge 2022. Sergi, Gianluca. The Dolby Era. Film Sound in Contemporary Hollywood. Manchester: Manchester University Press, 2004. Shannon, Claude. “A Mathematical Theory of Communication.” The Bell System Technical Journal 27, no. 3 (1948): 379–423 and 27, no. 4 (1948): 623–665. Shannon, Claude. “Communication in the Presence of Noise.” Proceeding of the IRE 37, no. 1, (1949), 10–21. Slavik, Karl M., and Stefan Weinzierl. “Wiedergabeverfahren”. In Handbuch der Audiotechnik, edited by Stefan Weinzierl, 609–685. Berlin: Springer-Verlag, 2008. Volmar, Axel and Judith Willkomm. “Klangmedien.” In Handbuch Medienwissenschaft, edited by Jens Schröter, Simon Ruschmeyer, and Elisabeth Walke, 279–288. Stuttgart: J.B. Metzler, 2014. Wayback Machine. “Oval Archive.” Accessed January 18, 2020. web.archive.org/web/20070709154158/http://www.meso.net/oschatz/oval/. Wermuth, Jürgen. “Dynamik-Erweiterung durch neuartigen Studio-Kompander.” Funkschau 47, no. 18 (1975): 103–196. ______ 99 ______