BECAUSE he was on his way to becoming a hometown doctor in Springfield, Minnesota, when a part-time job at a hearing-aid repair shop changed his life. BECAUSE he founded the Professional Hearing Aid Service in 1967, soon acquired Starkey Laboratories, and became a missionary for the human ear, determined to improve not just hearing equipment but hearing itself. BECAUSE his worldwide medical empire and outreach program now encompass 33 facilities in 18 countries, and his clients include astronaut Buzz Aldrin, actor Kirk Douglas, countless baby-boomers, and five of the last six U.S. presidents. BECAUSE he has kept it local, maintaining his Twin Cities headquarters and turning the area into a nexus of global hearing-aid innovation. BECAUSE he has vowed never to turn away someone who cannot afford to pay, and his Starkey Hearing Foundation undertakes 150 charitable missions a year, dispensing devices from Argentina to Uzbekistan. BECAUSE he recently returned from South Africa, where a thousand children, many having traveled a day by foot and bus, heard their parents' voices for the first time. BECAUSE the foundation's star-studded "So the World May Hear" awards gala raises more than $1 million annually. BECAUSE he is keeping abreast of high-tech advances, such as a computer-software processing breakthrough that enables the hearing device to automatically adjust to the listener's sound environment. BECAUSE May is Better Hearing Month, and no one should have to imagine a " world without the soulful rapture of a cello or the faint flutter of a bird taking flight. BECAUSE he truly believes "we can help almost everyone."