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Word of AM Stereo Patent-Holder Leonard Kahn’s Death Spreads

‘Genius,’ ‘pioneer’ used to describe inventor

As word of Leonard Kahn’s passing has spread, Radio World has heard from admirers.

Broadcast veteran Herb Squire confirms to Radio World that the head of Kahn Communications passed away from natural causes earlier this month in Florida at the age of 86.

There is no obituary or death notice.

Best known for his AM stereo system that actually dates back to 1960, Kahn also created the “Symmetra-peak” in the late 1950s. This passive device equalized the positive and negative audio peaks being sent to a station’s transmitter and helped increase the modulation density by several decibels in the days before sophisticated multiband audio processing systems, according to Squire.

Squire knew Kahn since 1969. They worked together with the AM stereo system at WQXR and WQEW in New York. “My wife Laurie and I would go to dinner with Leonard and his wife Ruth on numerous occasions. I also was an expert witness for a few of the court cases” Squire recalled.

In addition to AM stereo, Kahn also invented Powerside and its outgrowth, Cam-D, an in-band, on-channel technology for digital radio. Users need special receivers to receive Cam-D.

In 2006, Kahn filed suit in the Southern District Court of New York, claiming that iBiquity Digital, Clear Channel and other entities were behind an effort to block the sale of his Cam-D receivers by favoring iBiquity’s digital radio system. In filings to the FCC on the same subject, Kahn added Radio World to the list. He subsequently created a website called “Wrath of Kahn” to make his point.

Dave Bialik, Project Manager for CBS Radio in New York, called Kahn a genius who was also opinionated, and a broadcast pioneer. “He spoke at many of the sessions I planned at the AES over the years,” according to Bialik.

Radio World contributor Tom Osenkowsky worked with Kahn at WNAQ(AM,) Naugatuck, Conn. to install an STR-84 exciter when Sage Broadcasting bought the station. Osenkowsky called Kahn a “brilliant engineer,” and added that Kahn’s AM stereo system was not effectively promoted.

After Kahn left New York for Florida several years ago, he would call Squire from time to time. The two would discuss the merits of some of the newer technology he was developing. “Although he was eccentric, and single-handedly would take on the world to prove his point, Leonard Kahn was a good friend and will be remembered,” Squire summed up.