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How The THX Noise Was Created

Posted by ryuzaki0 on from the audience-is-listening dept.

devilsbrigade writes "The blog MusicThing is running an interesting interview with Andy Moorer. Mr. Moorer is the man who created the sound called Deep Note, now heard in every THX-enabled movie theatre. The interview is originally from last year, but the tech-heavy discussion is still a timeless analysis of a great sound." From the article: "The score consists of a C program of about 20,000 lines of code. The output of this program is not the sound itself, but is the sequence of parameters that drives the oscillators on the ASP. That 20,000 lines of code produce about 250,000 lines of statements of the form "set frequency of oscillator X to Y Hertz. The oscillators were not simple - they had 1-pole smoothers on both amplitude and frequency. At the beginning, they form a cluster from 200 to 400 Hz. I randomly assigned and poked the frequencies so they drifted up and down in that range."

2 of 243 comments (clear)

  1. Some tangential "Deep Note" trivia by doesitmakeitsick · · Score: 5, Interesting
    This always amused me: http://www.benedict.com/Audio/dre/dre.aspx When the Napster maelstrom hit the recording industry, Dr. Dre, along with Metallica, was one of the first to hurl accusations of copyright infringement at the popular file sharing site.

    Dr. Dre is furious that people are using Napster to download his song "Lolo" without permission or license - an obvious "copyright infringement". The irony is that the prominent feature of that song is a sound that Dr. Dre appropriated without permission or license - an obvious "copyright infringement"?

  2. TODO: log random number generator seed by natophonic · · Score: 5, Interesting
    Some months after the piece was released (along with "Return of the Jedi") they lost the original recording. I recreated the piece for them, but they kept complaining that it didn't sound the same. Since my random-number generators were keyed on the time and date, I couldn't reproduce the score of the performance that they liked. I finally found the original version and everybody was happy.
    Whew!

    I was in a somewhat similar spot a few years back, where a script I'd written to generate random data for load testing a server, used date and time as a rand() seed. One set of data I generated uncovered a weird threading issue, and it was pretty reproducible with that dataset. Then a disk crash wiped the dataset. I still had the script, but couldn't seem to get another dataset that would repro the issue.

    In addition to being better about backups, I now log whatever random seed is used to generate a dataset like that.