 Steve Temmer, the president of New York City’s Gotham Audio, heard about the experiment and commissioned 50 units of what would be sold as the Gotham Delta-T 101 in 1971, introducing digital delay to the live sound industry.In 1972, Lee filed a patent for a device that could compress or expand the time duration of sound waves while preserving normal sound quality.That year, Lexicon introduced Varispeech, an electronic speech compressor for use in the language instruction market, specifically to help blind students access text more quickly and persons with speech disorders study spoken language.