The record press in which the character Winslow Leach is disfigured was in fact a real pressing plant (it was an injection-molding press at an Ideal Toy Company plant). William Finley was worried about whether the machine would be safe, and the crew assured him it was. The press was fitted with foam pads (which resemble the casting molds in the press) and there were chocks put in the center to stop it from closing completely. However, the machine was powerful enough to crush the chocks that it gradually kept closing. It is commonly believed that Finley pulled his head out of the press just in time to avoid being injured, and that his scream in that scene was genuine, but this is an exaggeration. Finley was quickly pulled out by grips and the record press scene, along with most scenes in the movie with little dialogue, was filmed without sound, and the talking and sound effects were dubbed in later. At a Phantom of the Paradise convention, Finley exaggerated the story and said that his scream was "for real", although he may have meant that he was able to conjure up a very real scream in post-production by thinking back to his memories of the incident.
In an interview with the New York Times, the two members of Daft Punk cite this as "our favorite film, the foundation for a lot of what we're about artistically", and claim to have seen it over twenty times. Paul Williams, who composed the music of the film and played Swan, appeared on Daft Punk's album Random Access Memories.
When Swan (Paul Williams) is adjusting Winslow Leach's (William Finley) voice, the singer is not Finley but Williams. This makes it a little in-joke when Swan announces that the voice is "perfect".
The single-edit, "time bomb in the car trunk" sequence is an homage to Orson Welles's famous opening for La Soif du mal (1958).
The "electronic room" in which Winslow Leach composes his cantata is an actual recording studio, The Record Plant. The walls covered with knobs are a huge, custom-built Moog electronic synthesizer. Dubbed TONTO, this instrument was featured on several albums by the pioneering electronica duo T.O.N.T.O.'s Expanding Head Band, and it still exists. TONTO is now on permanent exhibit at the National Music Center in Calgary, Alberta, Canada and is still available for use to any artist.