On a balmy evening in late June, about 120 guests of the Swiss watchmaker Jaeger-LeCoultre had just taken their seats in a temporary theater set up in the outdoor central courtyard at Westfield Century City mall in Los Angeles, when a disembodied host greeted them over the loudspeakers.

“There is a reason why you are here,” the deep masculine voice intoned. “It is the common urge that drives you to seek beauty. For thousands of years, human beings have been trying to define and measure its appeal. This is the arithmetic equation of beauty you are about to discover.”

To lovers of art and design, the remarks might have recalled the golden ratio, a mathematical term that dates to ancient times and describes the ratio between two numbers of approximately 1.1618. It is said to apply not only to mathematics but to art and architecture, creating balance and symmetry.

The traveling sound and light concert was conceived and designed by the Swiss watchmaker to celebrate the golden ratio as the theme of its 2023 introductions and to promote its classic rectangular Reverso design. The timepiece, introduced in 1931, was inspired by the golden ratio and reflects the clean lines and rectilinear shapes of the Art Deco movement of the era.

“At Jaeger-LeCoultre, we are creative and we love know-how,” Catherine Rénier, the brand’s chief executive, said in her welcome to the audience. “It is why we are always bridging and exploring the relationship between watchmaking and other forms of art.”

Then, the star of the show, the British pianist, composer and music producer Tokio Myers, took the stage. Against a backdrop of digital projections, Mr. Myers, whose given name is Torville Ashburn M. Jones, performed the 10-minute, four-part piano symphony “Timeless,” which he composed after visiting Jaeger-LeCoultre’s factory in Switzerland’s Vallée de Joux in December.

The three-hour show, which featured the Los Angeles-based L.E.Orchband and a solo multi-instrumental performance by Mr. Myers, was a prelude to a weekend of free public events at Westfield Century City that included watchmaking demonstrations and some 15-minute live performances by Mr. Myers.

Jaeger-LeCoultre first staged the show in June in Shanghai and is scheduled to present it again Sept. 14-17 at the Battersea Power Station in London. Performances in additional cities, including Dubai in mid-December, are being planned.

On a follow-up video call in early July, Ms. Rénier said the collaboration with Mr. Myers — who joined the call from a beach in Greece, where he was vacationing with his family — was the latest in Jaeger-LeCoultre’s year-old Made of Makers program. It is a series of partnerships with creators outside watchmaking, including the Parisian pastry chef Nina Métayer, the Korean digital media artist Yiyun Kang and the French visual artist Guillaume Marmin, designed to inspire cross-disciplinary exchanges.

“We have not worked before with any musical artist,” Ms. Rénier said. “This was the objective — to embark on a totally different experience, to showcase the golden ratio from another angle, maybe less expected than architecture or design.”

Mr. Myers, 39, the 2017 winner of “Britain’s Got Talent,” is known for his classical-meets-contemporary-dance-music mash-ups. He said that once he understood what Jaeger-LeCoultre wanted, he plastered his studio in the English countryside with images from the Art Deco era. Next, he composed a symphony in four chapters, representing nature, science, art and design, corresponding to the four sides of the rectangular Reverso.

“I needed to study all the Art Deco lines, shapes and designs to figure out, how can I replicate this musically?” Mr. Myers said. “From there, it was all about finding the tempo. Then I realized, hold on, why don’t I incorporate the golden ratio formula into beats per minute?”

Employing the same G minor key throughout “Timeless,” Mr. Myers maintained a lively tempo of 161.8 beats per minute (to evoke the golden ratio), adding synthesizers, spiral sound effects and percussive elements to symbolize the lines and silhouettes of Art Deco design.

“The piano is the thread throughout the ‘Timeless’ piece, the cogs that keep turning in the watch,” Mr. Myers said. “The rest is all experimentation.”

Ms. Rénier praised Mr. Myers’s work as a “bridge” between classical music and modernity, and likened it to the brand’s own efforts to connect mechanical watchmaking techniques of the past with the present. “We felt this was very close to our world,” she said.

Mr. Myers said he felt much the same way. After visiting the Jaeger-LeCoultre factory in Le Sentier, he said he felt a kinship with the brand that underscored the similarities between his artistic pursuits and those of the “geniuses in their lab jackets who are creating these watches.”

“Like the watchmakers, you’ve got to keep trying until you crack the code,” Mr. Myers said. “You know when it’s perfect. We’re all searching for that moment where it’s like, ‘O.K., I see the vision now.’”