Lurtsema hosted the classical music show Morning Pro Musica on radio station WGBH (FM) in Boston, Massachusetts from 1971 until his death in 2000. He was known among public radio listeners throughout New England for his sonorous voice (which was "described as having the quality of warm fudge") and his phrasing, which frequently included long pauses. The pauses, anathema to mainstream radio, were either tolerated or loved by his loyal listeners. He said: "I'm not afraid of dead air. I don't think there's anything wrong with a quiet spot once in a while. When I pause I'm visualizing my audience, the person I'm speaking to. I always imagine I'm speaking to someone in particular."

Lurtsema also performed a great deal of voiceover work, especially for public-television documentaries and classical pieces with narration. He was featured as a reader in several of the Revels' recordings.

In addition to his work in radio, Lurtsema was a composer. In 1975, he was awarded a lifetime scholarship at the New England Conservatory of Music, where he began to study composition and theory. Among the songs, chamber works and film scores that he wrote is music for bassoon quartet that became the theme music for the TV show Julia Child and Company.