October 2023

Innovation Happening Every Day
Today we enjoy advanced innovations that are easily recognized.
Editorial By J. Martins

  On December 10, 1915, Danish engineer Peter L. Jensen and Edwin S. Pridham presented a groundbreaking invention to the public in Golden Gate Park in San Francisco, CA. It was the first practical application of a moving-coil loudspeaker, using a horn to amplify the sound. They successfully took their invention to market, building speakers for public address systems and for radios under the Magnavox brand.

Much earlier, British physicist, inventor, and radio pioneer Oliver Joseph Lodge described the concept of the dynamic loudspeaker and was even granted a patent for a dynamic, moving-coil loudspeaker concept. Ten years after Jensen and Pridham successfully demonstrated a moving-coil loudspeaker, in 1925, Edward W. Kellogg and Chester W. Rice applied for the first of many loudspeaker-related patents. The "Sound reproducing apparatus" was issued in 1926, and the "Loud-Speaker" patent was issued in 1929.

Much later, Edgar Villchur (working with Henry Kloss in Acoustic Research) received a patent for the much improved "acoustic suspension" loudspeaker. When Kloss left to form KLH (with Malcolm Low and J. Anton Hofmann) in 1957, and started to sell loudspeakers under license from Villchur, only then did other manufacturers notice and adopt the technology. Altec Lansing even turned down the opportunity to buy the original patent from Villchur.

In our September 2023 issue, audioXpress published a thorough analysis of the C2S Concentric Coplanar Stabilizer (C2S) loudspeaker technology, developed by Dinaburg Technology. The article from Roger Shively (Shively Acoustics International) used today's state-of-the-art numerical simulation and measurements to illustrate the full benefits of this patented integral coaxial speaker cone with a stabilizing ring radiator. Besides providing powerful subwoofers in thin and compact boxes, Mikhail Dinaburg's invention enables lower distortion, extended frequency range, higher efficiency, and improved speech intelligibility in a multitude of speaker and even headphone applications. Today, as in 1957, 1925, and 1915, bringing innovations to market that are actually recognized by consumers, requires a huge engineering effort.

Coincidently, while working on Roger Shively's article, I came across a reference to an interesting earlier approach to the dual concentric cone — the ALTEC Lansing Biflex speakers. And I was curious as to why this approach seemed to have been forgotten. In a note to Roger Shively, he confirmed that he was extremely familiar with the concept, stating, "Neal House and I messed around with the 'biflex' cone ideas in our early days (1986 to the early 1990s) at Harman. We called it a cone decoupler, in an attempt to control the breakup better. After I wrote Harman's first FEA/BEM program (good ol' NASTRAN and FORTAN and a VAX machine the size of small bedroom...), I think I convinced myself it was futile. It didn't stop us from trying to get more into a simple package. There was a co-motional tweeter (an independently driven tweeter cone mounted to the apex of the cone). And, a version of the cone decoupler with a dual voice coil — one coil for mids and highs and the other for the bass."

It sounded extremely familiar. Even with all the resources of one of the largest audio companies in the world, some concepts are simply not feasible with the technology of the time.

When people say that "speaker technology has not changed much in more than 100 years," it's an obvious demonstration of how many times we fail to recognize how much happens every year in the speaker world. In the editorial I wrote for The Audio Voice in January 2022, "CES 2022 Audio Highlights," unknowingly I documented one of those key moments. As I wrote, at that show Swedish company Exeger — the company behind the revolutionary Powerfoyle solar cell material that enables self-charging consumer electronic devices — promoted a joint demo with an innovative Dutch startup, called Mayht (later acquired by Sonos for its Heartmotion speaker driver technology). They demonstrated a proof-of-concept, compact speaker using Exeger's Powerfoyle material applied to the cabinet, allowing the speaker to keep playing without any power source. A great example to showcase the benefits for consumer electronics brands.

Fast forward to 2023, and Urbanista, a Swedish lifestyle audio brand, announced the world's first self-charging wireless speaker with an integrated Powerfoyle membrane. The Urbanista Malibu is a portable, waterproof design that self-charges whenever exposed to indoor or outdoor light. It was officially launched at IFA 2023 in Berlin and is available to order now.

I wonder what the early pioneers would say about a light-powered loudspeaker?

J. Martins
Editor-in-Chief

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