How the iconic THX Deep Note was made

Originally published at:


I remember going to the cinema, it was some time ago though, my memory is fuzzy.


I don’t remember it from cinemas, only home video. I suppose I just forgot encountering it in theaters.


Cinema? Cinema? Nope, sorry, you’re going to have to give me some hints, here.


D major… the happiest of all keys.


Totally true, the Butterkist jingle is in D major.

(Fact made up, may not be true.)


In the olden days people used to go to big rooms to watch television. It was a long time ago though, I think it was back when they wore powdered wigs and ruffs.


I’m going to the cinema, right … oh, damn - just another lockdown fantasy. I was so nearly there! Sigh.


Watching this, I kept thinking they must not have noticed the use of synthesizers in music for the last 50+ years. I’m sure I’ve heard the slow building of a chord in music somewhere, but I can’t remember exactly where. Of course the use of 5 channels in a theater auditorium makes a big difference, so the frequency response, dynamics, and movement make it more exciting. But all of those things have been done for ages.

What’s the big deal?

Well… looks like it is an open chord D with A, except right at the top there’s an F# making it DMaj. But only in the sheet music - I can’t hear any major 3rds in the THX showreel.


I have bookmarked this page from 2009 on how to recreate the THX sound using the programmatic sound system SuperCollider:

It is, effectively, the direct descendant of the original effort: programming “oscillators” to perform a particular sound variation.

It’s a super approachable and interesting explanation of the concepts that went into making Deep Note, in a step-by-step tutorial.

1 Like
1 Like

The randomness at the beginning conjures (for me) an orchestra tuning up before a show.

Cool how the random rising waves come together to sound like a Shepard Tone, giving the illusion of rising in pitch much more than it actually does.

The sequence informs us that before THX, and the Tomlinson Holman crossover, movie sound was muddled, uncorrelated, and indistinct, but THX tunes the sound.

As opposed to D minor, which I hear is the saddest of all keys.

1 Like

Yes, I heard that


Someone at a sound art event I was at a while back had a version of the code used to generate this sound, they could just run it and generate a slightly different one each time. Some of them sounded hilariously wrong

Thanks for the post. The full story can be found on my web site. They don’t let me put a link here but if you take my handle, jamminpower, and surround it with the usual stuff you will find it. Go to “Music” then “THX”.