Songfacts®:

• Imagine this: Deep Purple's lead vocalist, Ian Gillan, sitting in a school desk decades ago, daydreaming not about grand adventures, but about…a doorknob. Yes, a doorknob. "The first essay I wrote at school was about a doorknob," he told Mojo magazine.
  
  One can only assume the teachers had quite the time explaining that to Ian's parents. He took the everyday door accessory and brought it to life, "handled, fondled, twisted, turned, and slammed shut." Really, it sounds less like a piece of hardware and more like a misunderstood friend.
  
  In the mid of these ruminations, young Ian dreamed up a fantastical concept: a portable door, his own magic escape hatch from life's more inconvenient moments. "Wouldn't it be handy to carry a portable door around?" he thought. "Then you could slip in and out of situations whenever you wanted." Practicality at its finest.
  
  Years later, this slice of fantasy found its way into "Portable Door," the first single off Deep Purple's 23rd album, =1.
• "Portable Door" was released as the first single from =1. The song marked a new era for the band, as it was their material to feature new guitarist Simon McBride, who replaced Steve Morse in 2022.
• McBride noted that the tracks on =1 reflect what the five band members create together in the rehearsal room. Many of the songs, including "Portable Door," were written in the first album sessions "and literally came together in 5 or 10 minutes."
• Deep Purple played "Portable Door" live for the first time on May 1, 2024, at the Singapore Rockfest 2024 at Fort Canning Park in Singapore.
• The album title, =1, symbolizes the band's philosophy of unity amidst complexity, suggesting that everything eventually simplifies down to a single, unified essence.
• =1 is Deep Purple's fifth collaboration with producer Bob Ezrin, who has produced every Deep Purple album since 2013's Now What?!