Why is the company's name Sonic

"As SONIC started to expand and open new locations, Smith learned that the name Top Hat was already trademarked. In 1959, he and first franchise owner Charles Pappe decided to change the name to SONIC Drive-In, stylized with capital letters. The new name fit right in with the existing slogan: “Service at the Speed of Sound.” Both the slogan and the new name were inspired by SONIC’s newfangled intercom ordering system." https://www.rewindandcapture.com/why-is-sonic-drive-in-called-sonic-drive-in/

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