{"id":7034,"title":"History of Electronic Sound Modification","kind":"biblio","url":"https://www.videohistoryproject.org/history-electronic-sound-modification","version":"815a5b7027fd666b442894b63643d171fd39c7ab8212a27773b47475ed5d16fe","modified":"2011-06-22T20:57:12+00:00","credits":[{"role":"Author","name":"Harald Bode"}],"authorKeys":["Bode, Harald"],"subjects":[],"metadata":[{"label":"Publication","value":"Journal of the Audio Engineering Society","url":null},{"label":"Date","value":"October 1984","url":null},{"label":"ETC archive","value":"ETC0174","url":null}],"citations":{"page":"\u0022History of Electronic Sound Modification.\u0022 Video History Project, Experimental Television Center, 2011. https://www.videohistoryproject.org/history-electronic-sound-modification.","publication":"Harald Bode. History of Electronic Sound Modification. Journal of the Audio Engineering Society. October 1984.","risUrl":"https://www.videohistoryproject.org/citation/7034.ris"},"links":[{"label":"Scanned document","url":"https://archive.org/details/ETC0174","relationship":"linked document; contents not retrieved","contentType":"application/pdf"}],"sections":[{"name":"body","source":"VHP record body","generated":false,"characters":32737},{"name":"summary","source":"existing VHP generated summary","generated":true,"characters":755}],"content":{"section":"body","source":"VHP record body","generated":false,"text":"INTRODUCTION The history of electronic sound modification is as old as the history of electronic musical instruments and electronic sound transmission, recording, and reproduction. Means for modifying electrically generated sound have been known since the late 19th century, when Thaddeus Cahill created his Telharmonium. With the advent of the electronic age, spurred first by the invention of the electron tube, and the more recent development of solid-state devices, an astounding variety of sound modifiers have been created for filtering, distorting, equalizing, amplitude and frequency modulating, Doppler effect and ring modulating, compressing, reverberating, repeating, flanging, phasing, pitch changing, chorusing, frequency shifting, analyzing, and resynthesizing natural and artificial sound. In this paper some highlights of historical development are reviewed, covering the time from 1896 to the present. THE ELECTROMECHANICAL ERA To give a more complete account on this history, it is important to include the time span that preceded the purely electronic era, and also to include some history of electronic (and electrical) instruments whose sound modification devices formed an integral part of the entire system. A classic case is the Telharmonium, by Thaddeus Cahill which was built around 1896 [I]-[10]. This instrument used the principle of additive tone synthesis for sound manipulation and modification. The individual tone colors were built up from fundamentals and overtones, generated by huge dynamos. For the purpose of generating pure sine waves for the synthesis the individual generator coils were tuned with capacitors, another means of sound modification. THE ELECTRONIC ERA After the Telharmonium, and especially after the invention of the vacuum tube, scores of electronic (and electronic mechanical) musical instruments were invented with sound modification features. The Hammond organ is of special interest, since it evolved from Cahill\u0027s work. Many notable inventions in electronic sound modification are associated with this instrument, which will be discussed later. Other instruments of the early 1930s included the Trautonium by the German F. Trautwein, which was built in several versions. The Trautonium used resonance filters to emphasize selective overtone regions, called formants [11]-[ 14]. In contrast, the German Jorg Mager built an organlike instrument for which he used loudspeakers with all types of driver systems and shapes to obtain different sounds. In 1937 the author created the Warbo Formant organ, which had circuitry for envelope shaping as well as more complex filters than those used before. It had two sets of filters and a four-voice assignment keyboard [15] through which, for instance, voices 1 and 3 could be assigned to the first filter and voices 2 and 4 to the second filter. By making the pass regions of the filters mutually exclusive, complementary tone colors could be produced, which sounded very pleasing to the ear [16], [17]. In the late 1930s the Hammond Novachord was created, which also had formant filters for overtone modification and envelope shaping to produce tones like those of wind and string instruments [181, [19]. An interesting means of sound modification is found in the Electrochord by Oscar Vierling [16] and in the Miessner piano [20]-[23]. It was found that tonal qualities could be dramatically modified by changing the location of pickups (in this case capacitive) along the strings. For instance, when picking up the oscillations at the midpoint, all even harmonics would disappear, leaving only the odd harmonics, thus producing a hollow, clarinetlike sound. Placing the pickup at one third of the string\u0027s length, the third, sixth, and so forth harmonics would be canceled, and pickup points at other locations of the string length would produce yet different harmonic structures. The Electrochord as well as the Miessner piano were built without sounding boards, thus eliminating their damping effect and producing tones with longer decay times. The same was true for the Les Paul guitar, and it might be interesting to learn that Paul invented the solid-body guitar as far back as 1927 [24]. In his early experiments Paul used the magnets of the old-style headphones, which were equipped with steel diaphragms as membranes. The Gibson guitar evolved in 1941 and it has since been associated with an incredible number and variety of sound modification devices and methods, some of which will be discussed in more detail. From the beginning one important means of sound modification has been the tremolo and the vibrato, the tremolo being an amplitude modulation [25] and the vibrato a frequency modulation. It is interesting to note that post-source frequency modulation initially posed a problem. For this reason the first Hammond organs were equipped with means for amplitude modulation or tremolo. In the mid- 1940s a delay line with variable inductors was invented by Hanert, and after this a different type of variable delay line with a number of delay taps and a capacitive scanner was incorporated in the Hammond organ (Figs. 3 and 4) [261, [271]. By combining direct and the frequency-modulated signals, a type of choral effect was produced [28]. This laid the foundation for today\u0027s phasers. In the mid 1950s W. C. Wayne, Jr., proposed and built a purely electronic choral tone modulator for the Baldwin organ [29]. A different approach for choral tone modulation was taken by D. L. Bonham in the early 1960s [30], after he had created successfully a purely electronic vibrato modulator in 1958 [311. A unique contribution in sound modification devices was made by Homer Dudley through his creation of the voder and the vocoder in the late 1930s. The voder [32] was a keyboard-operated instrument controlling a number of bandpass channels for simulating the resonances of the human voice. With the addition of a tone source called the buzz source and a noise source called the hiss source, vowels and consonants of a speaker were imitated. The system became even more exciting when the voder, being an encoder, was combined with a decoder. This combination was called the vocoder, which comprised an analyzer for analyzing the speech and a synthesizer for remaking the same speech [331, [34]. For accomplishing this, the audio range was sliced up into a number of bandpass channels in the analyzer, which correspond to an equal number of bandpass channels in the synthesizer. In each analyzer channel a control voltage is generated with what we now call an envelope follower. This control voltage was then fed to the control voltage input of a voltage-controlled amplifier in the corresponding synthesizer channel. By listening to the recordings of the Dudley vocoder one notices that not only the speech articulation is being remade but also the speech inflection, which clearly indicates the presence of a pitch extractor - that works - as well as a pitch-to-voltage converter and a voltage-controlled oscillator. In the closing section of this article a few more aspects, modifications, and applications of the vocoder will be discussed. Thus far it has been observed that one important element in sound modification devices is represented by a variety of filters, such as the formant filters of the Trautonium and the Hammond Novachord, the complementary tone filters of the Warbo Formant organ, and the bandpass filters of the vocoder. Another instrument with strong formant filters was the Bode Melochord (preceded by the Melodium) [35], which was built for several major broadcast stations in West Germany by the late 1940s and the early 1950s. The Melochord was also equipped with circuitry for the control of attack and decay envelopes, vibrato, and the capability to play traveling formants, the frequency of which was keyboard controlled. In the Melochord for the Stockhausen Studio in Cologne the modular concept was adopted, by which external ring modulators, echo chambers, and the like could be included in the system [36] - [38]. A unique instrument combining many of the means of tone generation and sound modification known at that time was the RCA synthesizer which was created under Harry F. Olson. It made its debut in 1955 [39]-[41]. The RCA synthesizer is controlled by preprogrammed punched tape. It has such features as digitally controlled filters, control of attack and decay envelopes, digitally controlled pitch and waveshapes, random noise generation, and frequency and amplitude modulation. Around the same time Les Paul became famous with his multitrack guitar recordings, using tape speed transposition and the repetition effect. The well-known piece \u0022Whispering\u0022 was done in the early 1950s. Besides being an outstanding performer, Paul is an outstanding innovator. He introduced the multitrack recorder [eight tracks on 1-inch (25-mm) tape] in cooperation with Ampex. He also created Sel Sync. His repetition effect was done with a five-head recorder. His tape speeds were initially 60 and 30 in/s (1.52 and 0.76 m/s) and later reduced to 30 and 15 in/s (0.76 and 0.38 m/s). It was Paul who introduced the RIAA curve. Prior to the tape era, Paul created the repetition effect on 16\u0022 (406-mm) disks with five playback pickups in the same groove with the cutting head. This was in 1941. Les Paul, of course, stimulated many innovators, and due to his success encouraged them to work in the field of new sound effects. His influence in many areas is felt to this day. The author was so impressed by his work that he later developed a sound modification system consisting of a number of electronic modules, assigned to two separate outputs through a multiple-head tape loop device [42]. These modules also included a ring modulator. The ring modulator was at the time a relatively little known sound modification device, mainly used in single-sideband communication systems. The main reason was that up to the mid- or late 1950s it was known as a switching circuit, which would have sounded too harsh to be usable for sound modification. It was only after ring modulators were built with diodes, which operate in the square law region of their transfer function (as was the case with certain germanium diodes), that they started to perform as four-quadrant multipliers and became musically interesting [43], [44]. The author\u0027s modular sound modification system was built in late 1959 through 1960. In it the multiplier-type ring modulator and other sound modifying devices were used, such as an envelope follower, a tone-burst responsive envelope generator, a voltage-controlled amplifier, formant and other filters, mixers, a pitch extractor, a comparator and frequency divider for the extracted pitch, and a tape loop repeater with dual channel processing [45], [46]. The modular concept proved attractive due to its versatility, and it was adopted by Robert Moog when he created his modular synthesizer in 1964. This synthesizer included a variety of sound modification devices and system modules, such as voltage-controlled filters [47], envelope generators, voltage-controlled amplifiers, and sample/hold circuits. At a later date Bode ring modulators and Bode frequency shifters were also added to the Moog line. By the late 1960s sound effect devices such as the wahwah appeared in the popular entertainment field. The first successful wahwah was reported to have been the \u0022Cry Baby\u0022 which originated in England around 1965. It worked with germanium transistors. A quite effective wahwah was of course, the Moog voltage controlled low-pass filter capable of very pronounced resonances, which could be actuated by a voltage control pedal. It is understood that the Mutron, an envelope activated voltage-controlled filter, was widely used during the 70s. [48]. Another popular sound effect device, which started in the mid 1960s, is in the category of the so-called fuzz boxes. The story goes that the fuzz started with Jeff Beck making a guitar re","offset":0,"nextOffset":12000,"totalCharacters":32737,"complete":false},"rightsUrl":"https://www.videohistoryproject.org/terms-service"}