Page 66 - Spring 2015

Dr. Per V. brüel -100 Years
During WWII, it was difficult to get components for instru- ments to be produced in their company. Although Viggo Kjær was working in the radio industry and therefore had easier access to electronic components, the lack of cop- per wire was their biggest problem. However, one of their friends who was taking part in the resistance against the Germans turned out to be of great help to Brüel and Kjær. In the Bay of Køge, just south of Copenhagen, he cut away and stole about 1 km of the underwater telephone cable from the main communication line between the German occupation forces in Copenhagen and their headquarters in Berlin. This operation gave Brüel & Kjær enough copper wire for the rest of the war.
In 1944, Per had been offered and accepted an associate pro- fessorship at Chalmers University for three years. After the war, he stayed in Gothenburg for three days a week while the other days were spent in Brüel & Kjær A/S in Denmark. One instrument he particularly worked on in Sweden was an acoustic level recorder that was needed for measurement of reverberation time in rooms. This recorder was improved by the company and became one of their best selling prod- ucts. As Per Brüel said about this instrument, “Without any doubt the level recorder, apart from being a good business, also had improved Denmark’s position as a country, where they know something about acoustics.” Difficulties with the longtime stability of microphones made it necessary to de- velop a simple and transportable calibration device. It was a pure mechanical construction consisting of two pistons steered by a polished cam disc.
Noise in wooden houses, in particular, step sounds, was also a subject studied at Chalmers University, where a special tapping device using 5 steel hammers knocking 10 times per second was developed. This device was later standardized by the International Electrochemical Commission (IEC) in Geneva.
Due to his many contacts in Sweden, Per Brüel was involved in establishing the Swedish Acoustical Society in 1945. The interest in acoustics and in noise abatement was developing very fast during Per’s years in Sweden. In Sweden, they ex- pected a boom in house building in Europe after the war, and development of sound and thermal-insulating building materials had a high priority, which was advantageous to his laboratory in Gothenburg.
After Per had returned to Denmark in 1947, he was the di- rector of Danish Decca Navigator A/S for a year, where he established the Danish Decca system, but starting in 1948,
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he was employed full time by Brüel & Kjær A/S. The compa- ny had had a humble startup on a par with other companies such as Apple and Hewlett-Packard. Their first production site, after using the kitchen in Kjær’s apartment, was a rented space in a dressmaker’s workroom. The money was sparse and some limitations were imposed on Brüel and Kjær. As pointed out by Kjær, “We were happy to get room at Mrs. Dragby’s. The only thing was that she didn’t want any noise before 10 a.m. so we couldn’t show up until then.”
To finance the company start, Kjær sold his accordion and Brüel sold his Leica camera. This pattern of financial self- reliance characterized the company for the duration of Brüel’s and Kjær’s management. As Brüel once expressed, “I was scared stiff about borrowing money, if we did, we would die. It’s far too expensive. We didn’t want to be dependent on bankers; we wanted to be 100% self-financed.”
In 1945, the company rented and moved into a stable in Lyngby, just 10 km north of Copenhagen. The 3rd partner in the management of the company, the technician Holger Nielsen, joined the same year. This improved the financial situation. In 1948, Brüel & Kjær A/S bought their first prop- erty, a wooden army barracks in Nærum, 15 km north of Copenhagen. These are the premises where the company is still located today.
The three directors shared the activities in such a way that Brüel was responsible for product planning, research, and sales, Kjær was responsible for development, and Nielsen was responsible for instrument production. As long as the market only comprised Denmark and Sweden, Brüel per- sonally delivered the instruments to customers using his Nimbus motor bike.
When the market increased with the rest of Scandinavia and Europe, cars were needed, and in 1980, about 30 company cars were available. When the distance to customers in- creased with new customers outside Europe, “Brüel & Kjær Airlines” was established in 1956. The company eventually was the owner of a substantial fleet of aircraft, which made it possible for Brüel, who had a pilot’s certificate for flying one- and two-engine airplanes, to make airborne deliveries to any customer who was located near a general aviation air- port. In the mid-1980s, several employees in the company were asked to get pilot licenses to fly with Brüel due to the concern about his advancing age. Per finally solved this issue by hiring his flight instructor as his personal copilot. To the consternation of the passengers, the copilot was even older than Per.