Rudy Bozak

Rudolph Thomas Bozak (1910–1982) was an audio electronics and acoustics designer and engineer in the field of sound reproduction.

His parents were Bohemian Czech immigrants; Rudy was born in Uniontown, Pennsylvania.

Fresh out of college in 1933, Rudy Bozak began working for Allen-Bradley, an electronics manufacturer based in Milwaukee, Wisconsin.

Bozak would later employ Allen-Bradley components in his own electronic designs.

Bozak moved to the East Coast in 1935 to work for Cinaudagraph out of Stamford, Connecticut.

Two years later he was chief engineer.

At the 1939 New York World's Fair, a tower topped with a cluster of eight 27" Cinaudagraph loudspeakers in 30" frames with huge 450 lb. field coil magnets covered low frequency duties for a 2-way PA system at Flushing Meadows.

The loudspeakers were mounted into horns with 14' wide mouths and were each driven by a 500 watt amplifier derived from a high-power radio broadcast tube.

In June 1940, Electronics magazine published an article that Bozak had written about the design of the 27" loudspeaker.

During World War II, Bozak worked with Lincoln Walsh at Dinion Coil Company in Caledonia, New York developing very high voltage power supplies for radar.

Bozak joined C.G. Conn in 1944 to help them develop an electronic organ.

While in Elkhart, Indiana, he noticed that the human sense of hearing was unpredictable at best.

Years later, Bozak recounted this story about the Conn electronic organ project: "The general sales manager, who was a pianist and played organ, sat down and played the thing and said it was great, just what we were looking for. A week later he was invited back into the laboratory and sat down and played the instrument again. He didn’t play ten or fifteen bars when he said, This goddamn thing doesn’t sound right. What did you guys do to it?’ We said we hadn’t done anything. Well, he didn’t believe us. ‘You did something to it. You messed it up here,’ he said. ‘Restore it back to the way you had it.’ So what we did was let the damn instrument sit there for another week, and he comes back and plays it again. ‘Now this is the way it should be,’ he says."

In 1948 Bozak moved his family to North Tonawanda, New York to develop organ loudspeakers for Wurlitzer.

While there, Bozak experimented at home in a loudspeaker laboratory he housed in his basement.

One design of his featured a kettle drum shell as the loudspeaker enclosure.

In 1950 Bozak was hired as a consultant by McIntosh Laboratory to develop a square loudspeaker driver unit but it was not an engineering success.

Bozak met Emory Cook in the early 1950s; the two hit it off and began working in a shared warehouse basement facility in Stamford.

By the mid-1950s, Bozak had expanded into new quarters at 587 Connecticut Avenue in South Norwalk, with an export office in Hicksville, New York.

The foundation of Bozak loudspeaker design was the unique Bozak cone.

The woofer cone was molded from a slurry containing paper pulp, lamb's wool and other ingredients in a secret process.

The cone was made thicker at the center, becoming progressively thinner toward the periphery.

An additional doping of the inner area further strengthened the cone center.

The result was a cone with 'variable density' from center to rim with virtually no breakup or standing waves, the major sources of distortion in more conventional paper cones.

The original midrange and tweeter cones were paper.

Cook and Bozak thrilled the audio world in 1951 with Cook's ground-breaking stereo recording of train sounds at night: Rail Dynamics.

Together, Bozak and Cook implemented a stereo loudspeaker system that would be able to show Cook's stereo recordings to best effect.

The Concert Grand was the crown jewel of Bozak speaker systems since its introduction in 1951.

This refrigerator-sized speaker system originally contained four B-199 12" woofers, one 8 Ohm B-209 6" midrange driver and eight tweeters.

The B-310 and B-310A were the mono versions in which the tweeters were arranged as a sector of a sphere for widest distribution of high frequencies.

In 1952 he was making driver units for the McIntosh F100 speaker system.

Though these sold reasonably well, McIntosh did not develop the design further.

This experience led him to form his own company, Bozak Loudspeakers, in Stamford, Connecticut.

In 1961 the B-209 midrange cone was changed to a radical new design.

The material was very thin spun aluminum which took much of its strength from its curvilinear profile along the radius.

The cone received a thin coating of latex in order to damp the surface reflections that otherwise would occur on a metal surface which is vibrated rapidly.

The design was patented and was largely responsible for the superb transient response of the Bozak B-209B and B-209C midrange.

In 1961 the original B-200X paper-cone tweeter re-appeared as the B-200Y, using the same basic cone design of the midrange.

Bozak studied at Milwaukee School of Engineering; in 1981, the school awarded him an honorary doctorate in engineering.

Bozak married Lillian Gilleski; the two had three daughters: Lillian, Mary and Barbara.