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Louis Barron: Pioneer of Tube Audio Effects

by Phil Taylor

‘Forbidden Planet’ was one of my early experiences of science fiction. As a geeky kid into science, space and raised in the midlands of England this movie was a lifeline and undoubtedly one of the major reasons I’m working in audio electronics. The script, visuals and soundscore still hold their own in the light of movies made today some 60 years on and this article is my tribute to Louis Barron who, along with his wife Bebe, created that incredible soundscore for the movie.

An Early Electronic Music Studio

Louis Barron with one of his hand-constructed tube effects circuits

Louis Barron pictured with one of his tube effects circuits – Photo taken in his electronic music studio at 9 West 8th Street, Greenwich Village on January 1st 1956 by Walter Daran

Turn the clock back six decades to an era where the synthesiser was just an electronic gleam in Robert Moog’s eye and digital audio recording/sampling was an engineering dream. It’s easy to imagine this period as a ‘dark ages’ for electronic music, however a lively avant-garde music scene was in full swing and being fueled by the latest developments in vacuum tube electronics and new innovations in magnetic tape recording. A handful of pioneering composers such as Louis Barron embraced this eclectic technology and began designing and constructing their own electronic equipment in a quest to create exotic new sounds and explore uncharted musical territory.

Louis studied his music degree at University of Chicago, however he also possessed a flair for tinkering with electronics. Consequently, he built much of the equipment in his Greenwich Village studio, which looked more like an old radio repair shop than a recording studio. A collection of superb photographs were taken of the Barrons studio in 1956 at the time Louis and his wife, Bebe were working on the soundscore for the movie Forbidden Planet. In the foreground of this picture is Louis’ main tool of the trade, his 300B Oscilloscope (manufactured by Precise Development Corp, Oceanside N.Y.). On the bench in front of the ‘scope is a high voltage power supply and several of his hand-built circuits sat on top of a small section of perforated masonite (hardboard). These were primitive sound synthesis circuits based on tube relaxation oscillators, diode ring modulators and anything else Louis could come up to create interesting sonic textures. In front of Bebe is what appears to be an item of rackmount RCA equipment in small rack – the knobs are RCA manufacture. The rack looks like it might contain an RCA shortwave receiver, such as the model AR-88 and a patch bay with 1/4″ jack sockets. To Bebe’s left stands a custom-made ¼” mono Stancil-Hoffman transcription tape machine and behind her is another reel-to-reel machine on the desk where she also spliced tape for editing or to make loops. Louis is standing in front of a 19″ rack unit containing tube power amplifiers, a Precise 909 vacuum tube voltmeter, more homemade/modified tube gear including saw-tooth, sine, and square-wave oscillators and filters. The large box to his immediate left is yet another homemade creation, this time a 12″ paper-cone speaker mounted inside an impressive infinite baffle cabinet – designed to reproduce lower bass frequencies. The light-coloured unit on the right with six Daka-ware chicken knobs on its front-panel looks as if it might be the custom spring-reverb unit. On the far right is the 16mm Ampro Premier 20 projector they used to screen the work print of Forbidden Planet for music timings. Against the walls are several steel shelves containing 10½” magnetic tape reels, 16mm filmcans, technical manuals, tools, boxes of electronic and electro-mechanical components – the Barrons had put together one of the first electronic music studios in America. This floor plan shows the how they organised their equipment in their studio.

Magnetic Monopoly

Ampex VU Meter

Vu meter on the Barrons custom-built Stancil-Hoffmann tape machine. Plastic magnetised tape allowed sounds to be recorded in hi-fidelity and manipulated in new ways.

At this time (1948) magnetic recording/playback technology was not widely available to the general public, however the Barrons were fortunate enough to have connections with the Minnesota Mining and Manufacturing Company (3M) as Louis’ cousin was one of the executives there. 3M was one of the first companies to successfully coat plastic (acetate) tape with an emulsion of iron oxide particles – magnetic tape recording became a commercially viable reality. The new tape machines were much easier to work with than the old wire machines, making it possible to approach music composition in an entirely new way. The magnetised plastic tape media meant that Bebe could record and archive sounds of Louis’s circuits, building a working library, where she could post-process the material by adding reverb and delay and also by sometimes reversing and varying the speed of certain sounds. Possibilities for organising sounds appeared with tape editing, which permitted tape to be spliced and arranged with unprecedented precision – tiny fragments of sound could be cut, rearranged, spliced together and looped to create completely new sounds with little or no dependency on the live performance abilities of the musician. Multi-tracking was performed with three tape machines, where the outputs of two machines were manually synchronised and fed into an input of the third, recording two separate sources simultaneously. Meticulously hand-building circuits, recording them and further manipulating the material by adding reverb, delay, reversing, etc. was a time-consuming and laborious process, however the Barrons were sculpting magnificent and unique soundscapes with a bleak beauty and stark finesse not found in the work of their contemporaries.

Their thriving studio business brought in enough income to acquire additional equipment, including their Stancil-Hoffmann reel-to-reel custom built to Louis’s specification. Using their newly acquired equipment, the couple delved deeper into the study of musique concrète, recording everything and everyone. For a brief time, the Barrons held a monopoly on tape recording equipment and their connection with 3M, through Louis’ cousin, ensured they had a plentiful supply of magnetic tape for their projects. This established the Barrons as a successful working music studio, recording and releasing spoken word discs of Anaïs Nin, Tennessee Williams, and Aldous Huxley in a series called Sound Portraits.

Self-Destructing Tube Circuits!

Louis Barron ring modulator circuit

Louis catalogued his circuit designs on thousands of note cards like the one shown above.

One must remember that at the time (late 1940s), there was considerably less literature available to anyone experimenting in electronics. Louis would have almost certainly been a reader of Radio-Craft (later Radio-Electronics) magazine and perhaps owned a copy of the RCA Receiving Tube Manual. He spent a great deal of time pursuing his own path in sound synthesis and at one point was intensively studying the book Cybernetics or Control and Communication in The Animal and The Machine, by mathematician Norbert Wiener. He followed principles and equations described in the text, to design and construct many variations of custom oscillator and ring modulator circuits. The text is a dry read with some chapters being purely mathematical in nature, however there are several references to the practical application of vacuum tubes to mimic or replicate systems found within living organisms. For example, on page 153, Wiener states, “It is perfectly possible, for example, to cause any message going into storage to change in a permanent or semi-permanent way the grid bias of one or of a number of vacuum tubes, and thus alter the numerical value of the summation of impulses which will make the tube or tubes fire” – an attempt to model the function of a neuron (nerve cell).

An entire chapter is devoted to the topic of feedback and oscillation and describes a non-linear, oscillator more commonly known as a relaxation oscillator. This type of circuit is used to generate the sawtooth waveform that drives the raster scan in a T.V. set, creating the picture. Relaxation oscillators were constructed from gas – usually neon or argon – filled tubes known as thyratrons. These relaxation oscillator and ring modulator circuits were a few of the building blocks that Louis used to create his unique sounds. His approach was not to think in terms of classical signal processes such as filtering, amplification, oscillation, distortion, etc but to treat the circuit as a living organism going through a lifecycle – a completely new approach to sound synthesis. By manually adjusting an applied voltage or a variable resistor or capacitor, he could coerce a circuit into life where it would generate a managerie of weird bleeps, blurps, whirs, whines, throbs, hums, wails or screeches.

Vacuum tube technology is what made Louis’ circuit creations realisable. In the 1986 Keyboard Magazine interview he explains, “Tubes are forgiving. The grid of a power tube may be expected to take one or two volts. If you accidentally touch it with 300 volts, it’ll heat up, it’ll get red in the face. Take the voltage away and it’ll cool down, ready to do its normal thing. A transistor would blow in a fraction of a millisecond. And even if they don’t cost much, they’re a damn nuisance to keep changing.” In order to create electronic life, says Louis, “you have to be free to abuse the circuit.” That said, he pushed his creations to their limits often overloading and destroying them in his quest to discover outrageous new sounds before the circuits ultimately expired.

Forbidden Music

During the early 1950s they and their studio were hired by John Cage for his first tape work, Williams Mix – Louis and Bebe recorded over 600 different sounds, cutting, arranging and them to create a four and a half minute piece. The Barrons moved on to produce music and sound effects for several short experimental films, scoring three of Ian Hugo’s short films based on his wife Anaïs Nin writings, the most notable being Bells of Atlantis (1952). Their next big project was to provide incidental music to a conventional orchestral score for Forbidden Planet, however the Barrons ended up scoring the entire film, along with many of the film’s sound effects. Louis designed individual sound generator circuits for particular themes and motifs, rather than using standard sound generators – this was an innovative approach to composition, where each circuit had its own characteristic voice. It took them 8 months just to record the raw sounds and a total of three years to complete the soundscore. The scoring for Forbidden Planet blurred the boundary between sound effects and music so they became indistinguishable from one another – the Barrons had a vast new electro-acoustic territory to explore and began laying down the lines for the future of electronic and dance music.

Battle with the Invisible Monster (Forbidden Planet)

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The groundbreaking soundtrack for Forbidden Planet dazzled and amazed audiences, however the Musician’s Union took a more negative stance. In their narrow view that the Barrons work could not be considered as music (hence the bizarre term “electronic tonalities” on the film credits). The union were pedantic traditionalists and simply did not have the imagination to appreciate and understand music created with home-built electronics and tape machines. They forbade the Barrons from becoming union members and because of this they were not credited as being ‘proper’ composers and their score was never considered for an Academy Award nomination. The Barrons never scored another film for Hollywood.


10½ inch rape reel

¼” open reel audiotape on 10½” reel. Image by Lori Dedeyan. Courtesy of UCLA Library Special Collections.

Louis and Bebe continued to collaborate musically after they divorced in 1970 and persisted with their use of analogue circuits even after the invention of the Moog synthesiser – they had no interest in working with synthesised sounds as they didn’t possess the texture or complexity of the sounds they sculpted with custom designed circuits, sampled and processed manually – an opinion also held by one of their contemporaries, BBC Radiophonic Workshop composer Delia Derbyshire. After Louis’s death in 1989, Bebe ceased composing as she was dependent on his technical expertise to construct sound generating circuits [Jane Brockman: A conversation with Bebe Barron, 1992]. Bebe passed away in 2008. The circuits, tape reels and other equipment the Barrons used to create their music and the Forbidden Planet filmscore now reside with Louis’s son from his second marriage in his garage in the hills of Los Angeles [Susan Stone: The Barrons: Forgotten Pioneers of Electronic Music (NPR), 2005]. A whole wall of his garage is filled with shelves full of 1/4″ tape reels, still in pretty good condition considering their age. Some of these reels undoubtedly contain material that was edited out and did not make it to the final print of Forbidden Planet and others contain finished compositions by the Barrons that have never been heard before.

The old building that once housed the Barrons legendary studio still exists today and it can be found on 9 West 8th Street, Greenwich Village, just off 5th Avenue, New York. Sixty years on the ground floor is now a shoe shop – you’d never guess that the likes of John Cage, Anaïs Nin, Aldous Huxley and MGM staff would have stepped through this unassuming doorway half a century ago to be transported into a magical world of glowing vacuum tubes and whirring magnetic tape reels.

If you enjoyed this article then you might want to listen to ‘Return of the Monster from the Id’ which originally aired on Saturday 21st September 2013 evening as part of the BBC Radio 3’s ‘Sound Of Cinema’ season. You’ll hear some weird and wonderful Effectrode tube circuits – vacuum tube buffered ring modulator with neon relaxation oscillators to be exact – sparking, burning and screaming as they were pushed to their limits in an attempt to recreate some of the sounds from ‘Forbidden Planet’!