Laser Graphics, a company set up by two audiovisual experts in France, are trying to do something different with lasers: integrating sound and vision through a single synthesiser system which produces both music and images. Jean Marandet traces the development of their ideas, and describes how the new system operates.

Bernard Szajner and Patricia Negro started in the audio-visual field nine years ago, with just two Kodak Carousel slide projectors. The first steps were hard. Out of their audio-visual and publicity research, they made their first light shows. There were problems with lamp power and cooling, so the Carousels were modified. Others were bought. Manual and automatic dissolves were used and a 'Kaleidoscopic Projector' was built. They did light shows for the fun of it. Bernard, who read a lot of science fiction books, discovered lasers and their applications in the military and medical fields, and immediately conceived ways in which they could be used in light shows.

So he bought a Spectra-Physics helium-neon laser. It had a red beam and low power (15mW). But a laser by itself is of little use — it just sends out a straight beam. Thus Bernard and Patricia, who have no particular knowledge of optics or mechanics, thought up different methods of beam diffraction and scanning. They began work with the French band Magma, and with Gong. I saw the show for the first time in May 1975 at the Kinopanorama cinema in Paris, with Tim Blake (ex Gong) playing synthesiser. By this time, the equipment had increased: they had several helium-neon lasers and four Leitz Pradovit slide projectors that had been converted into monsters with separate power supplies, iris controls, and arc lamps (500W).

The effect was amazing: the music and lights were very closely linked, and made the Pink Floyd light show that I'd seen some months before look primitive. Then Bernard discovered the importance of prisms, diffraction gratings and effects produced by some photographic filters. He built more and more prototypes.

Bernard Szajner and Patricia Negro decided to set up a new company, Laser Graphics, specialising in the development of the laser's entertainment applications. At the end of 1975 they worked with The Who during their European Tour. They used for the first time two hired Spectra Physics argon lasers (4W each) and a machine called a 'Laser Synthesiser' that utilises prisms and mirrors moved by electric motors and fully remote-controlled by a 32-pair multicore cable. In 1976 Bernard found applications for lasers in publicity and this allowed him to buy his first Spectra Physics argon laser (which is expensive in France). Its colour ranges from blue to green and its power facilitates spectacular effects. The electrical supply is enormous (210V, 3-phase, 25A per phase) and the laser must be continuously cooled with water! Pumps are often used when there is insufficient water pressure.

In May and June 1976 they worked with Go (Stomu Yamashta, Stevie Winwood, etc) at the Royal Albert Hall, London, and in Paris. In December 1976 they worked for a month in St Eustace church in Paris, using, in addition to their normal setup, a second argon laser. The effect was extraordinary. They succeeded in creating false perspectives — the church seemed to fall down, beams twinkled and flashed and light seemed to totally invade the air and the pillars. In May 1977, Bernard and Patricia played a show in the Paris Planetarium with several different electro-acoustic bands. The sound was quadrisonic, produced with a Midas mixing desk and JBL speakers. More than 9000 people came to see the show.

But throughout the month, while improvising live with the control panels (which had about 300 different controls: speed variation of rotating mirrors; solenoid laser-beam shutters; frequency generators driving X-Y scanning systems and so on), the need for more sophisticated apparatus became obvious. And another idea came out, which was that the best way to control the emotions created through the audio-visual show was to create the music at the same time.

In August 1977, Bernard, who had wanted to play synthesisers for a long time, discovered the Mini-Moog, ARP Odyssey and Oberheim synthesisers. He recorded tapes on a Teac A3340 and bought an Oberheim digital sequencer. The tapes were impressive, so Bernard recorded a demo-tape of forty-five minutes in a 24-track studio. In December, he ordered a new French modular synthesiser, built by RSF of Toulouse, about the same size as the Moog Series III or Roland System 700. Bernard's system will include 72 synthesiser modules (VCOs, VCAs, Filter banks, etc), four analogue sequencers, two digital sequencers, digital filters, and electronic percussion.

At the beginning of March 1978, Bernard showed me his new stage setup (fig 1). The rhythmic information (gate and clock synth outputs) is used to trigger shutters and the various electronic control parameters of the laser beams. Musical information is analysed in each control panel (amplitude and frequency). Each input can be routed to any electro-optic function. (For example, all motors are controlled by VCAs so the amplitude of music can be made to produce a proportional voltage which can control the motor speed.) All laser functions are modular like the synthesiser:
- oscillators (VCO)
- envelope generators (ADSR) controlled by gate out or clock out from the sequencers
- motor and scanner drive amplifiers controlled by VCO or external modulation inputs.
Fig 2 shows an example of a laser control function.

The lasers — all Spectra-Physics — include two argon lasers, two helium-neon lasers, and a new 'Dye Laser' that transforms blue and green to yellow and orange. Between laser synthesiser and 'laser-machine' (including optics, mechanics, and scanners) there is a multiplex remote control system; all data is coded, passed through a double-screened cable and then decoded in the laser machine. As they'd worked day and night for several weeks to present the Planetarium show, Bernard and Patricia, plus a few friends, are working to finish these devices in two months. Flight cases are ready for all the standard modules and for the lasers. Bernard tells me that the show, called 'ZED', will appear in England in Autumn 1978.

Bernard and Patricia are always interested to work with bands. They obviously have a partiality for synthesiser players, but Bernard says: 'We cannot make a light-show for people who consider lasers as effects: there is no relation between their music and the light-show. Indeed, they fear that the lasers will throw their music into the shade. We like to create atmospheres that help the musicians to express themselves.' Bernard ends with an interesting idea of his own about light shows:

'All the visuals are considered as a language, not as effects. We play visions as a musician plays sounds and now, in the new experience, we will simultaneously play visions and music.'