The Kay Sona-Graph Sound Spectrograph was an invaluable tool for the analysis of telegraphic systems and in many cases, the encryption of voice systems. In the original instrument developed in the 1950's, the recording was displayed on a piece of paper called a sonogram which showed a 2.4 second sample over an 8 kHz frequency range.

The DSP-5500 Sona-Graph is a dedicated,  non computer-based, real-time, audio spectrum analysis instrument which was designed "from the ground up" for high speed signal analysis and display. The instrument is the current iteration of many generations of Sona-Graph which Kay has manufactured since the early 1950s.

Though supplanted by computer-based systems for some applications since its introduction in 1987, the DSP-5500 Sona-Graph continues to be widely acclaimed for its unique capabilities in real-time signal scanning, editing, analysis, and teaching in the diverse fields of bioacoustics, linguistics, speech pathology, forensics, singing analysis/training, and signal/intelligence. The 5500 contains a computer interface which allows data to be exported to a computer and then analyzed with other programs such as the KayPENTAX Computerized Speech Lab (CSL).

The Sona-Graph can store a twelve second sample of sound, which can be viewed (and listened to) for later
reference. The display is three-dimensional: the X-axis representing time, the Y-axis frequency, and the Z-axis amplitude.

The sona-graph consists of three components: a printer,  monitor, microphone and the operators console. The Sona-Graph Model 5500 analyzes sound, using a multiple processor system. It converts acoustic signals into a superficial visual display, valuable for use in the study of acoustic signals.  (Photo courtesy UCLA)


The company was founded in 1947 as Kay Electric Co. by Elmo Edward “Bud” Crump. Born in St. Louis, Missouri, on June 1, 1916, Mr. Crump graduated from the University of Missouri with a degree in electrical engineering. Throughout World War II, he worked at Bell Telephone Laboratories on fire control radar for the U.S. Navy and held numerous patents in this field.

In 1948, Mr. Crump, along with a partner, founded Kay Electric Co. in Pine Brook, New Jersey. Kay Electric became a major innovator in the electronics field and a supplier of instrumentation to industry and the US government. In 1951, Kay Electric was licensed by Bell Labs to develop the first commercial version of the sound spectrograph called the Sona-Graph. The Sona-Graph became the preeminent instrument in the acoustic analysis of speech, signals intelligence analysis, and animal vocalizations such as whale, bird, and dolphin communications. Most major universities throughout the world also used the Sona-Graph for linguistic analysis.

In the 1960s and 1970s, Kay was mostly active in radio frequency (radar and TV) industrial electronics. RF attenuators, which originated during this period of the company's history, continue to be a part of Kay's
product line today. By 1970, Kay Electric was incorporated as Kay Elemetrics Corporation with Mr. Crump as its president. It was then that Kay began to develop the speech therapy, voice, and swallowing analysis instrumentation for which it is so widely recognized today.

In 1987, after more than forty years in Pine Brook, NJ, the company relocated its headquarters to Lincoln Park, NJ, located 25 miles (40 km) west of New York City . Mr. Crump officially retired in 1994 but remained active in the business for consulting and selected engineering projects until his death on February 22, 2002. He is survived by his wife of 61 years, Mary; a brother; two sisters; nine children; 25 grandchildren; five great-grandchildren; and one great-great grandchild.

On March 17, 2005, the PENTAX Medical Company announced that it had acquired all of the operating assets of Kay Elemetrics Corp. Kay will continue its operations under the new name KayPENTAX, a division of the
PENTAX Medical Company.

Credits and References:

1)  Chris Collin <collin(at)mondenet.com>
2) Kay Pentax http://www.kayelemetrics.com/Product%20Info/5500/5500.htm
3) Kay Pentax http://www.kayelemetrics.com/companyhistory.htm
4) Kay Pentax http://www.kayelemetrics.com/Publications/comkay82.htm#Kay%20Founder%20Remembered
5) UCLA http://www.linguistics.ucla.edu/faciliti/facilities/acoustic/acoustic.html
6) Oberlin  http://www.oberlin.edu/con/divinfo/voice/obsvac/equip.html#DSP

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Aug 19/06