Deep Note is the name of THX's audio logo, a distinctive synthesized crescendo sound. It was created by Dr. James "Andy" Moorer in 1982, then an employee of the Lucasfilm Computer Division. The sound is used on trailers for THX-certified movie theatres and video releases.
The sound is a registered U.S. trademark (serial number 74309951). The registration contains the following description of the sound:
- The THX logo theme consists of 30 voices over seven measures, starting in a narrow range, 200 to 400 Hz, and slowly diverting to preselected pitches encompassing three octaves. The 30 voices begin at pitches between 200 Hz and 400 Hz and arrive at pre-selected pitches spanning three octaves by the fourth measure. The highest pitch is slightly detuned while there are double the number of voices of the lowest two pitches.
Moorer has been quoted as saying, "I like to say that the THX sound is the most widely-recognized piece of computer-generated music in the world. This may or may not be true, but it sounds cool!"[1]
Cultural status
The perceived loudness of the trailers was parodied by television series Tiny Toon Adventures (in the How I Spent My Vacation made-for-video movie; "The audience is now deaf."), and The Simpsons in the episode "Burns' Heir", in which the noise causes eyeglasses to shatter and heads to explode. An excerpt from the Simpsons parody, with Grampa Simpson yelling, "Turn it up!" was later used in an actual THX trailer. LucasArts themselves also parodied the THX slogan "The Audience Is Listening" in The Curse of Monkey Island, as the game starts up with a choir of chittering monkeys which grows bigger and louder in the spirit of Deep Note, and ends with the slogan "CMI - The Monkeys are Listening". After the opening logos in "Bug Too!" for the Sega Saturn, a similar version of the THX jingle is heard as we see Bug vacuuming his floor, plus it becomes "BHX - The Bugs are Listening."
Rapper Dr. Dre was sued in 2000 by Lucasfilm, then-owner of THX, for using an unauthorized cover of "Deep Note" on his 2001 album. [2]
A version of Deep Note is included as an easter egg in the BitTorrent client µTorrent.