Deep Note

[2] The U.S. trademark registration for the first version of the sound contains this description of it:[3] The THX logo theme consists of 30 voices over seven measures, starting in a narrow range, 200 to 400 Hz, and slowly diverging to preselected pitches encompassing three octaves.

Given that it was written and debugged in 4 days, I can't claim the programming chops to make 20,000 lines of working code that quickly.

[7] In April 2015, THX introduced a new trailer called Eclipse, which was accompanied by an updated, "Dolbyized" and more powerful version of the Deep Note, also created by Moorer.

"[10] Eclipse would be the only appearance of the regenerated version as starting with trailers Sphere and Genesis (both made to utilize the 4K video resolution), the remastered Deep Note was used instead.

The authors quote synthesizer builder Tom Oberheim as saying that the original analog form is much richer than the "digital perfection" evident in the sound logo so familiar to cinema-goers.

[14] Lucasfilm, then-owner of THX, sued rapper Dr. Dre in 2000 for using an unauthorized cover of Deep Note in the opening track "Lolo (Intro)" on his 1999 album 2001.

The Deep Note causes multiple things in the theater to explode seemingly from acoustic resonance, and ends with Abraham Simpson yelling "Turn it up!"

[18] Jacob Collier recreated the THX Deep Note in "100,000 Voices", the opening track to his 2024 album Djesse Vol.