The ‘Luminaphone’, Harry Grindell Matthews & Bernard.J.Lynes. UK, 1925

The Luminaphone (image: Illustrierte Technik für Jedermann: Heft 18 1926)

The Luminaphone of 1926 was one of a long line of inventions by the British inventor Harry Grindell Matthews, well known at the time for his much publicised invention of a ‘Death Ray’ in 1923 – an unsubstantiated or proven method of destroying objects and stopping electric engines through an invisible ray-gun. Matthew’s roster of inventions included a light controlled submarine (from which he received a £25,000 prize from the British admiralty), a mobile projector for projecting images onto clouds, an early method of recording sound on to film (1921), an underwater submarine detector, ground-to-plane radio-telephone, and a self-righting flying machine, amongst many others.

Diagram showing the operation of the light beams through the perforated dome to a selenium cell, an arrangement that optimised the use of the photo-cells.(image: Illustrierte Technik für Jedermann: Heft 18 1926)

The Luminaphone, patented in 1925 (Patent GB254437A ), was an early example of a photo-electric technique for creating pitched tones (originally derived from optical sound film technology); in this case a series of light beams – each light beam representing one frequency or note – were projected through a rotating perforated metal dome onto a selenium photo-cell that generated a pitched voltage pulse. The frequency of the pitch was determined by the frequency of the perforation in the metal dome. The luminaphone’s three octave keyboard had one lamp per key (a total of 36 keys and lamps) – when a key was pressed the assigned lamp would illuminate and project through the rotating perforated dome onto the photo-cell, generating the relevant pitch.

Functional diagram of the Luminaphone. (image: ‘Science and Invention’ February 1926)

The size and shape of the perforations determined the pitch, intensity and tone quality of the instruments tone – although, presumably, this would require stopping the machine and manually changing the rotating dome to change the sound or intensity.

Matthews planned to produce a commercial version of the instrument but the Luminaphone never evolved beyond the one prototype model.

(image:Technik für Jedermann: Heft 18 1926 )

Harry Grindell Matthews. Biographical Details:

Harry Grindell Matthews. born on 17 March 1880, at Winterbourne, South Gloucestershire.UK. Died:11 September 1941, Swansea, Wales UK.

Harry Grindell Matthews, a prolific British inventor, became an electronic engineer while serving in the Second Boer War (1900). Matthews many  and often fantastical inventions provoked controversy due to his penchant for publicity and unwillingness to reveal his methods – most famously with his military ‘Death Ray’ gun of 1923.

After being rejected by the British military, Matthews travelled to France with the apparent aim of selling his Death Ray invention to the French army and after he was again rejected he travelled to the USA with his new invention, the Luminaphone, to raise funds and generate publicity for his new projects. In 1938 Matthews married the (extremely wealthy) Polish opera singer Ganna Walska and constructed a well protected laboratory and airstrip in  Tor Clawdd north of Swansea in the South Wales hills. Matthews later projects included liquid fuelled rockets and a high flying ‘Stratoplane’. Matthews died of a heart attack on 11 September 1941 before any of his inventions were put into practical production.

A 1925 image that purports to show Matthews ‘Death Ray’ in action on the Welsh island of Flat Holm.

Brooklyn Daily Eagle. July 20, 1924


UK Patent GB254437A.
‘Popular Science’ Magazine March 1926 p55
‘The Light Beam Piano’; Science and Invention. USA. magazine February 1926. P896
‘Lichtstrahlen Musik’ Illustrierte Technik für Jedermann: Heft 18 1926 p199





‘Pattern Playback’, Franklin S. Cooper. USA, 1949

Franklin Cooper with the Pattern Playback machine

The Pattern Playback was not a musical instrument as such but an early hardware device designed to synthesise and analyse speech, designed and  built by Dr. Franklin S. Cooper and his colleagues, including John M. Borst and Caryl Haskins, at Haskins Laboratories in the late 1940s and completed in 1950.

Diagram showing the function of the Pattern Playback machine
Diagram showing the function of the Pattern Playback machine

The device converted a picture or ‘spectrogram’ of a sound back in to sound. The ‘Pattern Playback’ machine functioned in a very similar way to the Russian ANS Synthesiser using a photo-electrical system; a mercury arc-light was projected through a rotating glass disc printed with fifty harmonics of a fundamental frequency as a way of generating a range of tones. The light is then projected through an acetate ‘black and transparent’ spectrogram image that lets through the portions of light that carry frequencies corresponding to the spectrogram. The resulting ‘filtered’ light hits a photo-voltaic cell which generated the final audible sound .

The Pattern Playback machine

Pattern Playback
The Pattern Playback machine

Several versions of the device were built at Haskins Laboratories and used up until 1976. The Pattern Playback now resides in the Museum at Haskins Laboratories in New Haven, Connecticut.


The history of speech synthesis

The ‘Hardy-Goldthwaite Organ’ Arthur Cobb Hardy, Sherwood F. Brown & duVal Radford Goldthwaite, USA, 1931

Hardy Goldthwaite Organ
Hardy Goldthwaite Organ

The Hardy-Goldthwaite organ was a type of early  analogue sampler, similar to the Welte Licht-Ton Orgel, The Superpiano and several other photo-electrical instruments of the period and was developed by the physicists Arthur Hardy and Sherwood Brown at the Massachusetts Institute of Technology at the request of DuVal R. Goldthwaite, chairman of the Interchemical Corporation (who apparently had originated the concept after working with Hardy on colour and ink chemistry). At the heart of the instrument was a single optical disc of photographed sound waves. The discs, created from translations of original instrumental sounds, rotate between a light a slit and a photo-electrical cell generating voltage outputs of various timbres. A small three octave manual keyboard operated a shutter within the instrument that projected a light beam through the specific tone on the disc correlating to the key’s pitch.

The instrument was said to be able to produce the timbres of an organ, trumpet, piano and strings – with the possibility of reproducing any sound that could be recorded to the glass disc.

Arthur Cobb Hardy

Arthur C. Hardy born Worcester, Massachusetts:1895 died: 1977.

Arthur Hardy was a physicist best know for his work with spectrometers and colour analysers and was the author of the default text on the subject ‘The Principles of Optics’ . After the WWI Hardy worked at Kodak Research Labs and then transferred to Massachusetts Institute of Technology where he became chair of MIT’s physics department.

Hardy became president of the Optical Society of America from 1935-36 and in 1935 Hardy filed a patent for the first spectrophotometer – a device for measuring and recording colour values. It could detect two million different shades of colour and make a permanent record chart of the results. The patent was assigned to the General Electric Company of Schenectady, N.Y. which sold the first machine on 24 May 1935. It used a photo-electric device to receive light alternately from a sample and from a standard for comparison. 

After the outbreak of WWII Hardy founded the ‘Visibility Laboratory’ which focused on applying optics to such problems as camouflage, misdirection of aerial bombardment, target location, visibility of submerged objects at sea.

'The Canadian Champion' Newspaper July 3rd 1930
‘The Canadian Champion’ Newspaper July 3rd 1930



‘A History of Sampling’ (Hugh Davies)

Electronic and Experimental Music: Technology, Music, and Culture. Thom Holmes

‘Modern Mechanix’ magazine USA 1931

The Canadian Champion Newspaper July 3rd 1930

The ‘Vibroexponator’ Boris Yankovsky, Russia 1932

Boris yankovsky in 1939
Boris Yankovsky in 1939

Boris Yankovsky (1904-1973) worked with the Multzvuk group as a pupil of Arseney Araamov at Mosfilm, Moscow from 1931-32. However he grew disenchanted with what he considered to be an over simplified way of approaching acoustics. Yankovsky realised that pure uniform  waveforms do not represent timbre and that a more complex spectral approach needed to be developed. In 1932 Yankovsky left Multzvuk to pursue his ideas of spectral analysis, decomposition and re-synthesis . His project was based on his belief that it is possible to develop a universal language of sounds using combinations of hand drawn spectral ‘sound objects’ (similar to the much later cross-synthesis and phase-synthesis techniques).

“I found the idea of synthesis while I was laboriously working on ‘drawn sound’. And this is the chain of my consideration:
The colour of the sound depends on the shape of the sound wave;
Graphical colour of the sound wave could be analysed and represented as the Fourier series of periodic functions (sine waves);

Consequently the sound wave could be re-synthesised back with the same set of sine waves. Nobody did this before the invention of graphical (drawn) sound just because there was not a technical means and  methodology for sound reproduction from such graphical representations of sound. As with electrons (the neutrons and protons) the number of which defines the quality of the atom, so do the sine waves define the quality of the sound – it’s timbre.

Drawn scale with angles to create pitch shift
Drawn scale with angles to create pitch shift

The conclusion: why not initiate a  new science – synthetic acoustics?
It would make sense if we could define (at least in draft) a sort of periodic table of Sound Elements, like Mendeleev’s Periodic Table of Chemical Elements. The system of orchestral tone colours has gaps between the rows that could be filled by a means of synthesis, like the gaps between Mendeleev’s Periodic Table of Chemical Elements have been filled with the latest developments in chemistry […] It is obvious that the method of selection and crossing of sound and instruments, which is similar to the method of Michurin (Ivan Michurin Russian Biochemist and Horticulturist), will give us unprecedented, novel ‘fruit hybrids’ that are technically unobtainable for a usual orchestra […]
(Yankovsky 1932-1940; 15,45)

“It is important now to conquer and increase the smoothness of tone colours, flowing rainbows of spectral colours in sound, instead of monotonous colouring of stationary sounding fixed geometric figures [wave shapes], although the nature of these phenomena is not yet clear. The premises leading to the expansion of these phenomena – life inside the sound spectrum – give us the nature of the musical instruments themselves, but “nature is the best mentor” (Leonardo da Vinci) […] The new technology is moving towards the trends of musical renovation, helping us to define new ways for the Art of Music. This new technology is able to help liberate us from the cacophony of the well-tempered scale and related noises. Its name is Electro-Acoustics and it is the basis for Electro-Music and Graphical Sound”.
Yankovsky 1934

To implement these theories yankovsky invented the Vibroexponator; No images or diagrams have survived but the Vibroexponator appears to be a process using a modified rostrum animation stand that allowed the photographed ‘spectral templates’ to be translated into audible sound and then combined into complex sound.

“The Vibroexponator is a complex, bulky tool for optical recording of synthetic sounds to the soundtrack of ordinary 35mm film by means of a specially produced intensive negatives. the instrument is partly mechanised and provides various motions to the original negative. The automation of the direction control is partially broken and requires extra repairs and maintenance, […] The slide copying tool is intended for production of intensive negatives from films with transversal soundtracks. it too is a massive construction. The gearbox at least a 100-fold safety factor and a great power”

Nikolai Zimmin from the MINI institute describes the Vibroexponator in 1939

Yankovsky spent the next decade working on his spectral theories and building a ‘Syntone Database’ of his spectral templates by recording and analysing hundreds of samples of instruments from Bolshoi Theatre as well as samples of vowels and speech.

Slide copying machine tool diagram
Slide copying machine tool diagram

Political repression in the USSR stopped the funding of Yankovsky’s work until 1939 when he met the young inventor Evgeny Murzin who shared Yankovsky’s vision of a universal synthesis tool (which later emerged as the ANS Synthesiser) . Yankovsky together with Murzin and Yevgeny Sholpo formed the ‘Laboratory for Graphical Sound at the Institute of the Theatre and Film’ where he completed the final version of Vibroexponator. Further development of the instrument and of Yankovsky’s theories of spectral sound was halted by the outbreak of World War Two, Yankovsky never returned to graphical sound.

The Multzvuk group

Multzvuk group was formed in 1930 by Arseney Araazamov to conduct research into graphical sound techniques. The group was based at the Mosfilm Productions Company in Moscow (one of the leading film production companies in Moscow, renamed Gorki Film Studio in 1948) and consisted of composer and theoretician, Arseney Araamov, cameraman and draughtsmen  Nikolai Zhelynsky, animator Nikolai Voinov, painter and amateur acoustician Boris Yankovsky. In 1931 the group moved to ‘NIKFI’,  the ‘cientific Research Institute for Graphic Sound’. Leningrad, and and was renamed the ‘Syntonfilm laboratory’. In 1932 NIKFI stopped funding the group who then moved to Mezhrabpomfilm and finally closed in 1934.

From 1930-34 more than 2000 meters of sound track were produced by the Multzvuk group, including the experimental films ‘Ornamental Animation’, ‘Marusia Otravilas’, ‘Chinese Tune’, ‘Organ Chords’, ‘Untertonikum, Prelude’, ‘Piruet’, ‘Staccato Studies’, ‘Dancing Etude’ and ‘Flute Study’. The Multzvuk archive was kept for many years at Avraamov’s apartment, but destroyed in 1937.


Electrified Voices: Medial, Socio-Historical and Cultural Aspects of Voice … edited by Dmitri Zakharine, Nils Meise

Graphical Sound Andrey Smirnov, Moscow, 2011

the ‘Nivotone’ Alexei Voinov. Russia, 1931

The Nivotone optical reader
The Nivotone optical reader

The animator Nikolai Voinov (1900-1958), part of Arseney Avraamov‘s group ‘Multzvik’ in Moscow, 1931, started his own method of optical synthesis. Instead of drawing or printing to film Voinov cut wave forms from strips of paper which were then optically read by his machine the ‘Nivotone’ (‘Paper-Sound’) and translated into sound by a photo-electric process.

The Multzvuk group

Multzvuk group was formed in 1930 by Arseney Araazamov to conduct research into graphical sound techniques. The group was based at the Mosfilm Productions Company in Moscow (one of the leading film production companies in Moscow, renamed Gorki Film Studio in 1948) and consisted of composer and theoretician, Arseney Araamov, cameraman and draughtsmen  Nikolai Zhelynsky, animator Nikolai Voinov, painter and amateur acoustician Boris Yankovsky. In 1931 the group moved to ‘NIKFI’,  the Scientific Research Institute for Photography for Film. Moscow, and and was renamed the ‘Syntonfilm laboratory’. In 1932 NIKFI stopped funding the group who then moved to Mezhrabpomfilm and finally closed in 1934.

From 1930-34 more than 2000 meters of sound track were produced by the Multzvuk group, including the experimental films ‘Ornamental Animation’, ‘Marusia Otravilas’, ‘Chinese Tune’, ‘Organ Chords’, ‘Untertonikum, Prelude’, ‘Piruet’, ‘Staccato Studies’, ‘Dancing Etude’ and ‘Flute Study’. The Multzvuk archive was kept for many years at Avraamov’s apartment, but destroyed in 1937.


Electrified Voices: Medial, Socio-Historical and Cultural Aspects of Voice …edited by Dmitri Zakharine, Nils Meise

‘Graphical Soundtrack’, Arseney Avraamov, Russia, 1930

Arseny Avraamov in Moscow 1923. (Russian: Арсений Михайлович Авраамов), (born Krasnokutsky [Краснокутский], 1886 died Moscow, 1944)
Arseny Avraamov in Moscow 1923. (Russian: Арсений Михайлович Авраамов), (born Krasnokutsky [Краснокутский], 1886 died Moscow, 1944)
Methods of synthesising sound using a photo-electrical system flourished during the late 1920s, particularly after the development of sound-film techniques around 1926. In brief, the technique involved projecting a light beam through a transparent strip (or glass plate or rotating disk) onto a selenium cell. A graphic representation of a sound wave drawn onto the transparent surface varied the intensity of the light beam which in turn generated a variable and corresponding voltage output from the selenium cell i.e. a variable pitch corresponding to the drawn graphic. This technique was much used in Germany during the 1930s – for example: Oskar Fischinger’s sound-film based Tönende Ornamente (1932),  Rudolph Pfenninger’s similar Tönende Handschrift (1932), Spielmann’s glass-disc keyboard, the Superpiano (1928) and Welte’s Licht-Ton Orgel (1936) with other examples from around the world including the Luminaphone (UK/USA 1925), the Hardy Goldthwaite Organ (USA 1930) and Pierre Toulon’s Cellulophone (F 1927). However it was in 1930s Soviet Russia that light-sound synthesis was explored with particular interest, possibly because of the mystical synaesthetic theories of the Russian composer Alexander Scriabin (1871–1915) who, even in the 1930s, exerted an immense influence over young soviet musicians.

The Russian avant-garde composer and theorist, Arseny Mikhailovich Avraamov is probably best known for his “Simfoniya Gudkov” or “Symphony of Sirens” (November 7, 1922, Baku, USSR – an epic production which involved a score that coordinated navy ship sirens and whistles, bus and car horns, factory sirens, cannons, the foghorns of the entire Soviet flotilla of the Caspian Sea, artillery guns, machine guns, seaplanes, a specially designed “whistle main,” and renderings of Internationale and Marseillaise by a mass band and choir.) Later, however, through his pursuit of new sounds and particularly microtonal tuning, Avraamov became a central figure in soviet optical sound synthesis.

Avraamov studied at the music school of the Moscow Philharmonic Society from 1908-11 but fled the country when the first world war broke, working, among other things, as a circus artist. Avraamov returned during the revolution of 1917 where he developed his own  “Ultrachromatic” 48-tone micro tonal system ( “The Universal System of Tones,” 1927). Avraamov later (1930) began to develop a technique of optical sound synthesis which involved hand-drawing geometrical representations of sound shapes and then repeatedly printing these shapes onto the audio-optical strip on a cine-film. 1Smirnov, Andrey, Sound In Z: Experiments In Sound And Electronic Music In Early 20th Century Russia, Walther Koenig, 2013, pp28-37. Avraamov’s technique bore a striking resemblance to those developed simultaneously by Fischinger and Pfenninger (circa 1930) in Germany, despite this similarity,  it seems that both soviet and German techniques were developed in isolation.

An example of Avraamov’s hand-drawn graphic soundtrack Moscow 1930-1. image:Smirnov, Sound In Z, p179.

“By knowing the way to record the most complex sound textures by means of a phonograph, after analysis of the curve structure of the sound groove, directing the needle of the resonating membrane, one can create synthetically any, even most fantastic sound by  making a groove with a proper structure of shape and depth”.2 Avraamov A. ‘Upcoming Science of Music and the New Era in the History of Music’. Musical Contemporary Magazine, 1916, No.6, p.85 

“Composer Arseny Avraamov at the scientific-research institute conducts the interesting experiments on a creation of the hand-drawn music. Instead of common sound recording on film by means of microphone and photocell, he simply draws on paper geometrical figures, then photographing them on sound track of the filmstrip. Afterwards this filmstrip is played as a common movie by means of film projector. Being read by photocell, amplified and monitored by loudspeaker, this filmstrip turns out to contain a well-known musical recording, while its timbre is impossible to relate to any existing musical instrument. Comrade Avraamov conducts now a study in recording of more complicated geometrical figures. For instance, to record graphical representations of the simplest algebraic equations, to draw molecular orbits of some chemical elements. In this research composer is assisted by a group of young employee of the Research Institute for Film and Photo. By the end of December Avraamov will finish his new work and to show it to the film-community. Quite possibly the listening of the abstracts of “Hand Drawn Music” will be organized in radio broadcast”3‘Drawn Music’. Kino, Moscow, 16.12.1931. Trans. AS. in: Smirnov, Sound in Z, 178

The Multzvuk group

Multzvuk group was formed in 1930 by Arseney Araazamov to conduct research into graphical sound techniques. The group was based at the Mosfilm Productions Company in Moscow (one of the leading film production companies in Moscow, renamed Gorki Film Studio in 1948) and consisted of composer and theoretician, Arseney Avraamov, cameraman and draughtsmen Nikolai Zhelynsky, animator Nikolai Voinov, painter and amateur acoustician Boris Yankovsky. In 1931 the group moved to ‘NIKFI’,  the Scientific Research Institute for Photography for Film. Moscow, and and was renamed the ‘Syntonfilm laboratory’. In 1932 NIKFI stopped funding the group who then moved to Mezhrabpomfilm and finally closed in 1934.

From 1930-34 more than 2000 meters of sound track were produced by the Multzvuk group, including the experimental films Ornamental Animation, Marusia Otravilas, Chinese Tune, Organ Chords, Untertonikum, Prelude, Piruet, Staccato Studies, Dancing Etude and Flute Study. The Multzvuk archive was kept for many years at Avraamov’s apartment, but destroyed in 1937.4Smirnov, Andrey, Sound In Z: Experiments In Sound And Electronic Music In Early 20th Century Russia, Walther Koenig, 2013, p181.


Much of the biographical information is from Andrey Smirnov’s pioneering work Sound In Z: Experiments In Sound And Electronic Music In Early 20th Century Russia, Walther Koenig, 2013. It is currently out of print but available here as a pdf download.

  • 1
    Smirnov, Andrey, Sound In Z: Experiments In Sound And Electronic Music In Early 20th Century Russia, Walther Koenig, 2013, pp28-37.
  • 2
    Avraamov A. ‘Upcoming Science of Music and the New Era in the History of Music’. Musical Contemporary Magazine, 1916, No.6, p.85 
  • 3
    ‘Drawn Music’. Kino, Moscow, 16.12.1931. Trans. AS. in: Smirnov, Sound in Z, 178
  • 4
    Smirnov, Andrey, Sound In Z: Experiments In Sound And Electronic Music In Early 20th Century Russia, Walther Koenig, 2013, p181.


The ‘Superpiano’ and ‘Symphonium’. Emerich Spielmann, Austria, 1928

Emerich Spielmann playing the Superpiano
Emerich Spielmann playing the Superpiano and a standard piano

Spielmann’s Superpiano, patented in 1927, was based on the photo-optical principle used in a number of instruments during the 1920s and 30s  such as the  Cellulophone , the Radio Organ of a Trillion Tones, the Sonothèque’ , the Welte Licht-ton Orgel and others.  In general this principle worked by projecting a light beam through a spinning glass disk onto a photo-electrical cell. The regular interruption of the light beam causing an ‘oscillating’ voltage tone. Spielmann’s innovative instrument used two rows of twelve black celluloid disks. Each disk had a series of holes cut in seven concentric circles equating to the waveforms of the seven octaves of a note – the light beam being picked up by selenium photo-electrical cells.

Anni Spielmann (Emerich's daughter) playing the Superpiano
Anni Spielmann (Emerich’s daughter) playing the Superpiano

The Superpiano created complex tones by allowing a combination of  ‘pure’ and harmonic sound waves of the same note; each note was duplicated with contrasting sound wave and harmonics  – hence two rows of twelve disks –  allowing the player to mix the sound waves of each note with a knee lever. Volume control was achieved by variable pressure on the manual keyboard via variable resistors dimming and increasing the lightbulb brightness – and therefore the note volume. The instrument’s overall pitch could also be altered while playing, by adjusting the speed of the rotating disks. Spielmann intended the Superpiano to be used as an affordable ($300) home keyboard which could be played like a piano but also a type of early sampling keyboard – ‘drawings’ of different instrument’s waveforms could be made on the celluloid disks, allowing the player to reproduce the “entire instrumental range of an orchestra” – or so the advertising claimed.

The celluloid disks of the Superpiano for creating tones and harmonics
The celluloid disks of the Superpiano for creating tones and harmonics

Spielmann’s instrument had it’s debut in 1929 at a concert organised by the Österreichische Kulturbund (Austrian Culture Union) on January 9, 1929 played by the renowned composer and pianists  Erich Wolfgang Korngold who played a piano with one hand and the Superpiano with the other. Later, On February 14, 1929, Spielmann presented the Superpiano on the Vienna radio station RAVAG featuring lectures on the theme of ‘Das Licht spricht, das Licht musiziert’ (Light speaks, light makes music).

Spielmann's Superpiano 1927
Spielmann’s Superpiano 1927 th e Museum of Technology, Vienna, Austria

The last Superpiano at the Vienna Technical Museum, Austria
The last Superpiano at the Vienna Technical Museum, Austria showing the celluloid disks and light bulbs

The last Superpiano at the Vienna Technical Museum, Austria
The last Superpiano at the Vienna Technical Museum, Austria

Several instruments seem to have been built but only one survived the ravages of WW2, sold to the Vienna technical Museum in 1947. Spielmann developed a modification of the Superpiano called the ‘Symphonium’;  where the Superpiano used organ-like sounds, the Symphonium was based on mixable combinations of orchestral sounds; woodwind, brass and strings allowing fifteen possible combinations of timbres (to the Superpiano’s two)

With the seizure of power by the National Socialists in Austria and Germany in 1933 the Superpiano project was disrupted and the instrument failed to become a commercial proposition; As an Austrian Jew, Spielmann’s situation became increasingly precarious , his license to practice as an architect was revoked in 1938. Spielmann fled to London with his daughter Anni, and then to New York where he became a naturalised US citizen in 1944. Spielmann seems to have continued the project in the USA but the instrument was probably overshadowed by the similar ‘Welte LichttonOrgel’ using similar technology (also Jewish escapees to New York), and dominance of the Hammond Organ in the home instrument market.

Letter to Spielmann advocating the  Superpiano from Albert Einstein. USA 1944

Spielmann's patent for the photo-electrical sound generator
Spielmann’s 1928 patent for the photo-electrical sound generator


Video of Peter Donhauser – Head of Division Fundamentals of Technology & Science at the Vienna Technical Museum – with the Spuperpiano:

first show of the superpiano 2

Superpiano editorial in the Southeast Missourian Newspaper. 1929
Superpiano editorial in the Southeast Missourian Newspaper. 1929

Contemporary newspaper clippings The Mercury (Hobart, Tas. : 1860 - 1954)
Contemporary newspaper clippings The Mercury (Hobart, Tas. : 1860 – 1954)

Contemporary newspaper clippings. Straights Times, Singapore 1929
Contemporary newspaper clippings. Straights Times, Singapore 1929

Front view of the Superpiano showing tone-mixing knee lever, pedals and loudspeaker
Front view of the Superpiano showing tone-mixing knee lever, pedals and loudspeaker

naturalisation papers of Emerich Spielmann. 1944
U.S. naturalisation papers of Emerich Spielmann. 1944

Emerich(Ernst) Moses Spielmann – 23.06.1873  Vienna, Austria – 1952 Elmhurst, Queens, New York USA. Biographical notes

Emerich Spielmann, was a Viennese architect born into a Jewish family in the mid-19th century in Moravia. His father was a merchant Hermann Spielmann (1842-1925), his mother Josephine Franzos (1850-1918). Spielmann studied after high school from 1892 to 1899 at the Institute of Technology at King Karl and Karl Mayr Eder . He then worked until 1903 in the Wilhelm Stiassny and Friedrich Ohmann architectural practise. In 1904  he began a collaboration with the architect Alfred Teller working in the Viennese secessionist style and later to neo-baroque and classical forms, until 1932,  when he worked independently with his own practice. As a Jew, in 1938 Spielmann’s  license to practice was revoked by the Nazi authorities. He fled to London 1939  with his daughter Anna on May 6 and arrived on August 22, 1944 in New York where he became a naturalised citizen in 1944. He l died in New York in 1952.


Peter Donhauser, Elektrische Klangmaschinen, Vienna 2007.

The archive of  Regina Spelman, Deborah Lucas, Dan Lucas

The ‘Cellule Photo Electrique’ or ‘Cellulophone’. Pierre Toulon & Krugg Bass, France, 1927.

Pierre Toulon's Patent for the Cellulophone
Pierre Toulon’s Patent for the Cellulophone

Invented by the French engineer Pierre Toulon aided by the electronic engineer Krugg Bass, the Cellulophone (“Cellule Photo-électrique”) made it’s debut as a prototype in France in 1927. The Cellulophone was an electro-optical tone generator instrument resembling an electronic organ controlled by two eight octave keyboards and a foot pedal board.

The sound was created by passing a light beam through slits in a vari-speed rotating disk. The single spinning disk was cut with a number of equidistant slits (54 slits for the lowest note) with different shaped masks to create varied timbres. The disks masked a light beam that flashed through the slits and on to a photoelectric cell, the speed of the rotating disk therefore determining the frequency of the output signal from a single vacuum tube oscillator.

The Cellulophone (copyright Tom Rhea, Keyboard Magazine 1977)
The Cellulophone (copyright Tom Rhea, Keyboard Magazine 1977)


Toulon’s Cellulophone won the Prix jean Bares in 1933:

Second prize (2,500 francs) was awarded to Mr.. Pierre Toulon, a father of three children and consulting engineer of the Electrical School , who made a large number of inventions, among which include “the relay arc” whose principle is applied in instruments referred to as “Thyratrons” and “Spark-gap convertors”, the latter enabling flattening  and straightening of even high powered electrical currents.

Mr. Toulon also invented a device called “Cellulophone” – a musical instrument keyboard developed by the Pleyel company, which is an organ extremely reduced in size.

One disk was used for all the notes of each octave therefore notes whose frequencies could not be generated by an integral number were out of tune. This system however gave the unique and unusual possibility of having a different timbres for each octave. The Cellulophone was one of a generation of instruments in the 1920-30’s using a photo-electric sound generation method; other examples being the “Licht-ton Orgel” , the “Photona” and the “Radio Organ of a Trillion Tones”. The increased sophistication and reliability of post war electronic circuitry marked the decline of light based synthesis after the 1940’s except for a few pioneers such as Daphne Oram who used a similar sytem not only to synthesise sounds but to sequence sounds.

Pierre Toulon proposed in the 1930’s a related technique of speech synthesis using fragments of optical film mounted on a rotating drum.

Rotating disc mechanism of the Cellulophone<em> (©Tom Rhea, Keyboard Magazine 1977)</em>
Rotating disc mechanism of the Cellulophone (©Tom Rhea, Keyboard Magazine 1977)

Extract from ‘La Revue hebdomadaire : romans, histoire, voyages.’ Paris, March 1928 which describes various new electronic instruments of the period including the Cellulophone:


Les concerts du professeur Theremin. Une expérience d’acoustique fort instructive. Battements électriques. Où interviennentles lampes à trois électrodes de la T. S. F. Le principe de l’éthérophone. Un précurseur. Piano etorgues radio électriques. Le cellulophone. Conclusion. On a beaucoup parlé ces derniers temps d’une rénovation de l’art musical par l’emploi d’instruments de musique utilisant la merveilleuse souplesse des ondes hertziennes. Les concerts donnés cet hiver à Paris par le professeur Léo Theremin, de Léningrad, ont attiré un nombreux public. Il n’est pas douteux que l’idée d’utiliser les ondes hertziennes à la production des sons puisse constituer une innovation heureuse. Essayons donc de décrire le merveilleux appareil du professeur Theremin et d’en faire comprendre le fonctionnement.

L’explication paraîtra très simple à tous les sans-filistes. Quant à mes autres lecteurs, s’ils veulent bien me prêter quelque attention, je suis certain qu’ils saisiront tout aussi aisément le principe de la musique radiophonique. Rappelons tout d’abord une expérience d’acoustique que chacun peut répéter, pourvu qu’il possède chez lui quelque instrument de musique.

Tout le monde sait que le son est produit par les vibrations de la matière et qu’il nous paraît d’autant plus aigu que les vibrations sont plus rapides. Lorsqu’on fixel’extrémité d’une tige d’acier, une lame de fleuret par exemple, dans un étau, et qu’après l’avoir écartée desa position on l’abandonne à elle-même, elle entre en vibration et produit un son, d’abord très grave, maisqui monte de plus en plus au fur et à mesure qu’on raccourcit la lame, ce qui augmente le nombre des oscillations par seconde. Les sons les plus graves que l’on puisse entendre correspondent environ à 30 vibrations par seconde, et les sons les plus aigus à 40 000. Entre ces limites s’étend toute la gamme des sons perceptibles.

Mettons en bran le deux diapasons identiques, donnant par exemple chacun le la normal, l’un d’eux ayant été désaccordé par un peu de cire fixée sur l’une des branches. Le diapason normal effectuant 435 vibrations par seconde, celui qui a été désaccordé en donnera par exemple 432. Dans ces conditions, lorsque les deux diapasons fonctionnent en même temps, on perçoit dans le son d’ensemble des renforcements et des affaiblissements sucessifs,des sortes de hou, hou, hou, répétés régulièrement etqu’on appelle des battements. L’expérience a permis de constater que le nombre deces hou, hou, hou. par seconde est exactement égal à la différence entre les nombres de vibrations par seconde que donnent séparément les deux diapasons, soit ici 435 diminué de 432. Il y a donc trois battements par seconde. Le phénomène est général. Chaque fois qu’on produit simultanément, au moyen d’appareils quelconques, deux séries de mouvements vibratoires dont les nombres d’oscillations par seconde sont différents, l’ensemble donne lieu à des renforcements et à des affaiblissements successifs,à des battements. Or les ondes hertziennes résultent d’une sorte de mouvement vibratoire d’un milieu hypothétique qu’on suppose répandu partout et auquel on a donné l’antique nom d’éther. Dans les ondes, dites entretenues, qu’utilise la radiophonie, les vibrations sont très régulières mais extrêmement rapides. Elles se produisent à raison de quelques centaines de mille par seconde. Envoyées directement dans un téléphone, ces ondes seraient sans actionsur lui, car à supposer qu’elles fussent capables de faire vibrer, suivant un rythme de quelques centaines de mille par seconde, la membrane du téléphone, nous serions incapables de percevoir des vibrations aussi rapides, pour les quelles notre oreille est atteinte d’une surdité absolue. Mais émettons simultanément, au moyen de deux appareils différents, deux séries d’ondes hertziennes, les unes, pour fixer les idées, à raison de ioo ooo vibrations par seconde, et les autres, à raison de 99 000. Leur production simultanée donnera naissance à des battements électriques, à des renforcements suivis d’affaiblissements des ondes hertziennes, dont le nombre par seconde sera égal à 100,000 diminué de 90,000. Et à ces battements électriques qui se produisent ainsi à raison de 1,000 par seconde, le téléphone peut être rendu sensible. Sa membrane oscillant à raison de r 000 vibrations par second eémettra un son aisément perceptible. Si donc, l’une des deux séries d’ondes demeurant invariable et se produisant toujours à la fréquence 100 000, nous avons le moyen de faire varier la fréquence de l’autre série d’ondes et de la rendre égale par exemple à 99,500, à 99,400, à 99,300. le nombre des battements, toujours égal à la différence des fréquences associées, sera successivement 500, 600, 700. par seconde. Le téléphone actionné par les battements fournira un son deplus en plus aigu, correspondant successivement à 500, 600, 700. vibrations par seconde. Et c’est là tout le secret de l’éthérophone. Des ondes hertziennes sont produites à la fréquence moyenne de 300 ooo vibrations par seconde par deux générateurs appelés hétérodynes. Si les deux séries d’ondes sont légèrement désaccordées, elles donnent lieu à des battements électriques qui, agissant dans un haut-parleur à la manière habituellement utilisée dans les réceptions radiophoniques, en actionnent la membrane et produisent un son. De la boîte où sont enfermées les deux hétérodynes émergent une tige métallique verticale jouant le rôled’antenne, et une spirale en fil de cuivre placée horizontal ement sur le côté. Le fonctionnement de l’appareil consiste à faire varier les constantes électriques de l’un edes deux séries d’ondes en approchant la main droitede l’antenne verticale et la main gauche de la spirale. Le premier mouvement fait varier la fréquence des battements et, par conséquent, détermine la hauteur de lanote le second mouvement agit sur l’amplitude des ondes et par suite sur l’intensité du son. De ces deux mouvements, le premier, qui doit suivre les notes de la partition musicale, est évidemment le plus compliqué etest de ce chef dévolu à la main droite le second est réservéà la main gauche en raison de sa simplicité.

L’idée qui est à la base de l’éthérophone n’est pas nouvelle. Dès 1917, les ingénieurs français travaillant au laboratoire de la tour Eiffel avaient songé à tirer un parti musical des battements radio électriques dont nous venons de parler. M. Armand Givelet, vice-président du Radio-Club de France, avait eu l’idée de marquer à lacraie sur le cadran du condensateur d’hétérodyne le réglage correspondant aux différentes notes de la gamme. En tournant rapidement ce condensateur variable et en arrêtant brusquement l’aiguille sur les repères du cadran, il était parvenu assez facilement à jouer des mélodies populaires simples. C’était, en somme, exactement le principe de l’éthérophone. Il a suffi de perfectionner quelques détails pour obtenir un appareil permettant deproduire des effets véritablement artistiques.

D’ailleurs, M. A. Grivelet a réalisé, il y a quelques années, le premier piano radio électrique. On a pu voircet instrument exposé récemment au premier Salon des Sciences et des Arts, au Grand Palais des Champs Élysées. Chaque note est produite par un circuit séparé, engendrant les vibrations sans qu’aient à intervenir des battements. De son côté, M. Bertrand a construit sous le nom d’orgue radio électrique un appareil d’un principe tout à fait analogue à celui du professeur Theremin, qui utiliseles battements électriques de deux hétérogynes, et dans lequel le son est diffusé par un haut-parleur de grand modèle. La variation de la hauteur du son est produite par la commande d’une manette qui se déplace devant un cadran comportant une gamme de trois octaves.

Le Cellulophone de M. Pierre Toulon n’est pas moins curieux. Son principe est tout différent. Il utilise la propriétédes cellules photo électriques, sortes de piles qui donnent naissance à un courant lorsqu’elles reçoivent un faisceau de lumière. En envoyant sur une cellule, non un éclairage continu, mais un éclairage intermittent qu’on peut réaliser en interposant entre la source lumineuse etla cellule un disque tournant perforé, la pile produit une succession de courants instantanés dont le nombre par seconde dépend du nombre des trous que porte le disqueet de sa vitesse de rotation. Envoyés dans un haut parleur,ces courants le font vibrer avec la même fréquence. La hauteur de la note musicale dépend ainsi du nombre de trous que porte le disque et de sa vitesse derotation, le timbre étant déterminé par la forme de cestrous. On conçoit qu’on puisse modifier à volonté la hauteur et le timbre, et obtenir des effets musicaux très variés.

Il serait difficile de prédire l’avenir qui est réservé aux appareils de musique radio électrique. Indiquons seulement qu’ils ont permis d’obtenir des effets artistiques très intéressants, et il ne serait pas surprenant que,grâce à eux, la musique, cette forme si élevée et si expressive de l’art qui a très peu évolué depuis des siècles,entrât dans une voie entièrement nouvelle.


From Le Genie Civil February 7, 1928

cellulophon from ‘le genie civil’ 18 February 1928



Donhauser, P.: Elektrische Klangmaschinen. Die in Deutschland und Österreich Pionierzeit, Boehlau Vienna 2007.

Rhea, Tom. Keyboard Magazine 1977.

Le Genie Civil February 7, 1928

The ‘Rhythmicon’ Henry Cowell & Leon Termen. USA, 1930

Henry Cowell and the Rhythmicon
Henry Cowell and the Rhythmicon

In 1916 the American Avant-Garde composer Henry Cowell was working with ideas of controlling cross rhythms and tonal sequences with a keyboard, he wrote several quartet type pieces that used combinations of rhythms and overtones that were not possible to play apart from using some kind of mechanical control- “un-performable by any known human agency and I thought of them as purely fanciful”.(Henry Cowell) In 1930 Cowell introduced his idea to Leon Termen, the inventor of the Theremin, and commissioned him to build him a machine capable of transforming harmonic data into rhythmic data and vice versa.

“My part in its invention was to invent the idea that such a rhythmic instrument was a necessity to further rhythmic development, which has reached a limit more or less, in performance by hand, an needed the application of mechanical aid. The which the instrument was to accomplish and what rhythms it should do and the pitch it should have and the relation between the pitch and rhythms are my ideas. I also conceived that the principle of broken up light playing on a photo-electric cell would be the best means of making it practical. With this idea I went to Theremin who did the rest – he invented the method by which the light would be cut, did the electrical calculations and built the instrument.”

Henry Cowell

“The rhythmic control possible in playing and imparting exactitudes in cross rhythms are bewildering to contemplate and the potentialities of the instrument should be multifarious… Mr. Cowell used his rythmicon to accompany a set of violin movements which he had written for the occasion…. The accompaniment was a strange complexity of rhythmical interweavings and cross currents of a cunning and precision as never before fell on the ears of man and the sound pattern was as uncanny as the motion… The write believes that the pure genius of Henry Cowell has put forward a principle which will strongly influence the face of all future music.”
Homer Henly, May 20, 1932

The eventual machine was christened the “Rythmicon” or “Polyrhythmophone” and was the first electronic rhythm machine. The 17 key polyphonic keyboard produced a single note repeated in periodic rhythm for as long as it was held down, the rhythmic content being generated from rotating disks interrupting light beams that triggered photo-electric cells. The 17th key of the keyboard added an extra beat in the middle of each bar. The transposable keyboard was tuned to an unusual pitch based on the rhythmic speed of the sequences and the basic pitch and tempo could be adjusted by means of levers.Cowell wrote two works for the Rythmicon “Rythmicana” and “Music for Violin and Rythmicon” (a computer simulation of this work was reproduced in 1972). Cowell lost interest in the machine, transferring his interest to ethnic music and the machine was mothballed.

Rhythmicon Discs
Rhythmicon Discs

After Cowell, the machines were used for psychological research and one example (non working) of the machine survives at the Smithsonian Institute. The Rhythmicon was re-discoverd twenty-five years after its creation by the producer Joe Meek (creator of the innovative hit single ‘Telstar’, 1961) apparently discovered abandoned in a New York pawnbrokers. Meek brought it back to his home studio in London where it was used on several recordings. This Rhythmicon was used to provide music and sound effects for various movies in the Fifties and Sixties, including: ‘The Rains of Ranchipur’; ‘Battle Beneath the Earth’; Powell and Pressburgers’ ‘They’re a Weird Mob’; ‘Dr Strangelove’, and the sixties animated TV series ‘Torchy, The Battery Boy’.The Rhythmicon was also rumoured to have been used on several sixties and seventies records, including: ‘Atom Heart Mother’ by Pink Floyd; ‘The Crazy World of Arthur Brown’ by Arthur Brown, and ‘Robot’ by the Tornadoes. Tangerine Dream also used some sequences from the Rhythmicon on their album ‘Rubicon’.

Rhythmicon Discs
Rhythmicon Discs


“Henry Cowell: A record of his activities” Compiled June 1934 by Olive Thompson Cowell.

The ‘Saraga-Generator’ Wolja Saraga, Germany,1931

The Saraga Generator
The Saraga Generator. Photo; Saraga family archives

The ‘Saraga-Generator’ was developed by the electrical engineer and physicist Wolja Saraga at the Heinrich-Hertz Institut Für Schwingungsforschung (HHI) in Berlin, Germany around 1931. The Saraga Generator was an unusual photo-electrical vacuum tube instrument originally designed to be used for theatrical production where the sound would be triggered by movement in front of the instrument.

Wolja Saraga working on the 'Saraga Generator' at the HHI, Berlin in 1932
Wolja Saraga working on the ‘Saraga Generator’ at the HHI, Berlin in 1932 (Photo; Saraga family archives )

The original instrument consisted of a single photoelectric cell mounted on the white painted inside surface of a box with a small ‘V’ shaped slit cut on one face. A low voltage neon lamp was placed at some distance from the box on a stage and the performers movements interrupting the light beam causing variations in pitch in a tone generated using the well established  heterodyning effect of two vacuum tubes. Later versions were designed to be played in a way similar to the Theremin with one hand held in the air controlling the pitch by interrupting the light beam –Envelope and timbre were controlled by manipulating a hand held switching device, the overall volume being driven by a foot pedal. The Saraga Generator was monophonic with a tonal range of four octaves.

The Saraga Generator was patented in 1932 and demonstrated at the Berlin Radio Exhibition (IFA Berlin) in the same year.

Wolja Saraga. Berlin, 1930s
Wolja Saraga. Berlin, 1930s

Saraga took a version of the Generator to London after he left Berlin for the UK in 1938 ( He also brought a Volkstrautonium purchased as a promotional model from Telefunken) . He gave several presentations of the instrument for the Institute of Musical Instrument Technology (Holloway Rd, London N7) in May 1945 entitled “A Homophonic or single-note electronic musical instrument with a photo electric cell as playing manual – demonstration of an experimental model” and searched for commercial applications for the instrument including film soundtrack music and musical therapy for blinded war veterans.

Wolja Saraga working at the HHI, Berlin 1932. (Photo; TU Archives, Berlin)
Wolja Saraga working at the HHI, Berlin 1932. (Photo; TU Archives, Berlin)

Difficulties in sourcing electronic components in post-war Britain hampered development of the instrument which was eventually overtaken by more sophisticated and versatile electronic instruments of the 1950s


Wolja Saraga (Born:3rd September 1908 Berlin; Died 15. February 1980, London)
Wolja Saraga (Born:3rd September 1908 Berlin; Died 15. February 1980, London)

Wolja Saraga: Biographical Notes

Saraga was a German Jewish Physicist, born in Berlin to a Romanian father and a Russian mother. Saraga studied telecommunications at the Heinrich Hertz Institute (‘Heinrich-Hertz Institut Für Schwingungsforschung’ or ‘HHI’) at the Technical University, Berlin under Prof Gustav Leithäuser – alongside luminaries such as Oskar VierlingHarald Bode , Winston Kock and Friedrich Trautwein.

It was during his time at the HHI that he began investigations into electronic musical instruments, his published papers detailing; a dual oscillator Aetherophone or ‘Theremin‘ , a ‘Poly-rhythmic Electronic Musical Instrument’ , The workings of the Volkstrautonium and his design for a photo-optical instrument, the ‘Saraga Generator’ first built in 1931. Saraga became a research assistant at the institute and later  a lecturer from1929-1933. He also studied physics and mathematics at the Humboldt University of Berlin , where he was awarded a Dr. phil. in physics in 1935.

Wolja Saraga’s ticket for the 1936 ‘Great-German Radio Exhibition’ (image; Saraga Family Archive 2016)

During his time in Berlin, Saraga was very energetic in promoting the potential of electronic music; He made several public presentations and demonstrations of electronic instruments including Theremins, Trautoniums and his own ‘Saraga Generator’. Saraga was also present playing the ‘Saraga Generator’ at the 1932/3 International Funkaustellung (IFA) where the first ever electronic musical orchestra performed (Das ‘Orchester der Zukunft’).

"Electric Concerts" with the electroacoustic "orchestra of the future", 1932/1933 On the occasion of the 9th and 10th IFA in Berlin 1932 and 1933 for the first time found concerts with "Electric Music" instead. They played by the so-called "Orchestra of the future" all electroacoustic musical instruments then available. The "Elektischen concerts" made at the time an exceptional level of interest and broad support in the public, as the cooperating with private Theremingerät Erich Zitzmann-Zerini [second right] the engineer Gerhard Steinke told while gave him this original image. The orchestra consisted of two theremin instruments Trautonium [by Trautwein], Heller desk [of B. and P. Helberger Lertes], a neo-Bechstein grand piano [for suggestions of O. Vierling, S. Franco, W. Nernst and H . Driescher], Vierling piano [electro Acoustic piano by O. Vierling], electric violin, electric cello and Saraga generator [a light-electric device by W. Saraga, in principle, similar to the Theremingerät]. Photo: archive Gerhard Steinke
A concert by the electroacoustic “Orchestra of the Future” at the 9th and 10th IFA in Berlin 1932. Consisting of: (L-R) Bruno Hellberger playing his ‘Hellertion’, unknown playing the ‘Electric Cello’, unnown playing the ‘Hellertion’ (?) Oskar Sala playing the ‘Volkstruatonium’, unknown playing the ‘Neo Bechstein Electric Piano’, Oskar Vierling playing the ‘Electrochord’ unknown playing the ‘Electric Violin’ Wolja Saraga (back of stage) playing the ‘Saraga Generator’ Erich Zitzmann-Zerini with the ‘Theremin’ Unknown playing the ‘Volkstrautonium’ (Photo: archive Gerhard Steinke)
It became clear to Saraga in 1935-6 that as a Jewish scientist he would have no future in the new National Socialist German Reich and began to apply to leave the country, first of all to Switzerland and then to the UK. Saraga finally left Berlin in 1938 at the age of 29. he was initially held for six months on the Isle Of Man Hutchinson Camp as a German internee but was given a position working for the ‘Telephone Manufacturing Company’ (or ‘TMC’) in St Mary’s Cray, Kent where, despite his unhappiness at his employers lack of interest in research, he remained until 1958.

A press card for a presentation by W.Saraga entitled 'Electronic Music'
A press card for a presentation by W.Saraga entitled ‘Electric Music – a presentation and musical demonstration of the Trautonium’. Berlin 1933. (Photo; Saraga Family Archive 2016)

Saraga then joined The Associated Electrical Industries Research Laboratory in Blackheath, London as a Research Scientist and Group Leader where he specialised in telephony filter design. In 1962, Saraga’s key contributions were recognised by the award of the Fellowship of the Institute of Electrical and Electronics Engineers, ‘for contributions to network theory and its application in communications’. In 1972, Saraga moved full time to Imperial College, London where he became a postgraduate lecturer and researcher in network theory and mathematics.

Saraga wrote a number of books and filed several patents on network theory and telephony.


Archives of the Heinrich Hertz Institute/Heinrich-Hertz Institut Für Schwingungsforschung, Berlin, Germany

CIRCUIT THEORY AND APPLICATIONS, VOL. 8, 341 (1980) Obituary of Wolja Saraga by J. 0. SCANLAN

Saraga, W. “Elektrische Klangfarbenerzeugung, in FUNK-Bastler” 1932, Heft 38, S. 594, zit. nach STANGE-ELBE 1993a, S. 15( “Electrical Timbre generation, into radio hobbyist” )

[Wolja] Saraga: Die “tönende Handschrift”, in: Funktechnische Monatshefte 1933, H. 10, S. 403-406, hier S. 406

W. [Wolja] Saraga: An Electronic Musical Instrument with a Photo-Electric Cell as Playing Manual, in: Electronic Engineering 17 (1945), Juli, S. 601-603

Obituary: IEEPROC, Vol. 128, Pt. G, No. 4, AUGUST 1981

Documents from the Saraga Family Archive 2016