Originally done in Germany in 1991, Robert Wilson's musical fable, The Black Rider, reached London's Barbican Theatre in February in a new language but with pieces of the old physical production. In the process of refurbishing and replacing these original elements, the Barbican adapted electrical elements to British standards. When the American Conservatory Theater, which co-produced, brought the work to San Francisco for a September opening, different theatrical, industrial, and regulatory standards in two countries compounded problems inherent in transferring any production.

Wilson designed scenery and lights for the show, too, the latter with associate LD Heinrich Brunke. “When it comes to color and lighting, Robert Wilson knows exactly what he wants, and he'll always spot when it's wrong.” says ACT production manager Ed Lapine.

The Barbican and ACT have similar lighting inventories, but this production called for equipment beyond the basics, including four followspots (Robert Juliat Korrigans), moving lights, and Howard Eaton dimmable fluorescent cyc lights. Brunke thought he could add two rented followspots to the two in ACT's stock, but after an exhaustive tech in London, the Barbican staff wanted four British followspots and contributed three; ACT rented a fourth.

“The production included dimmable fluorescents mounted into scenery, low voltage lights buried in set pieces, a 2.4kW HMI fixture for rear projections, motors built into several set pieces, and even electrified musical instruments” says Lapine. All required the equivalent of British power, he explains.

The Barbican's rider asked for transformers to provide 240V, the UK line voltage.

“They explained that 110v tools are common on British construction sites because of the lower risk of injury from electrical shock; transformers for 240V to 110V are readily available there,” says Lapine, who soon surmised that the Barbican was “not only using 240V…they ran at 50Hz, not at the 60Hz US standard.” Many electronic devices operate on multiple frequencies, but the great variety of equipment in The Black Rider package could introduce different and competing requirements of a system providing US power converted to UK standards.

It would be necessary to provide 50Hz and decide which gear absolutely required it. Lapine talked to US lighting professionals whom he thought might use international gear and to rental house staff but nobody had a prescription for providing 240V 50Hz.

The actual number of UK-powered lighting instruments and devices, including two packs of dimmers to run the lights, was fairly small, but first calculations suggested that ACT might need a relatively high capacity source.

How would Lapine satisfy Wilson's standards while working around differences in electrical standards?


The theatre could rent a diesel generator, which would sit on the street for the eight-week run, or it could locate a frequency converter of a size that would require 460V input, more service than the theatre had. “The diesel generator truck began to look attractive,” says Lapine.

Barbican staff returned to help spec a frequency converter that would tie into ACT's 208V backstage supply, but no company in the San Francisco Bay area had one. “In a bit of last minute miscommunication and second guessing, we received word from the followspot manufacturer's rep that the ballasts were not switchable.”

The biggest electrical load was in the followspots, and the spot booth was far from backstage, where a frequency converter would connect to ACT's company switches.

Lapine wondered: “Is there an alternative to the followspot ballasts?” “Are the followspot ballasts switchable to run off a 208V 60Hz supply?”

Meanwhile, the production was crossing the ocean and the Barbican technical manager went on vacation. “ACT's head electrician went to the US rep for Robert Juliat, the followspots' manufacturer…[who] reported that the ballasts should be switchable between UK and US electrical system. A lucky discovery!” says Lapine.

ACT decided to act safely and proceeded with the bigger frequency converter. The larger converter arrived just a few days later than planned and dropped into place effortlessly — and the ballasts proved to be switchable. Big Blue, the nickname ACT staff gave the frequency converter, continued to provide 240V 50Hz flawlessly through the run — an unqualified success.

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