The album Tubular Bells (with The Exorcist theme) accidentally contains morse code sent to UK military submarine

Originally published at: The album Tubular Bells (with The Exorcist theme) accidentally contains morse code sent to UK military submarine | Boing Boing

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I can’t figure out how to hear it in the second video at the link (which is obnoxious to sit through, hoping for the answer to finally be revealed!).

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The video is a waste of time. Human ears cannot hear a 16 Hz sound.

The sound on the video is just white noise in the 1,000s of Hz and has nothing to do with the low frequency submarine signal.

In the IEEE article the author used a software-defined-radio application on his computer to isolate the signal and demodulate it. He doesn’t say this in the article but I assume he was able to view the signal peaks (not listen to it) using a spectrum waterfall and that’s how he decoded the Morse message.

Edit: The signal is at 16kHz, not 16 Hz. 16kHz is audible but at the high end of the range. Not sure why the video would not have video of the spectrum display instead of photos. Thanks @ David_Guilbeaul

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A curious example of “The devil is in the details” or homeopathic audio?

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Those waterfall displays appear to be frozen, or screenshots; normally you will see the lower half of the screen moving downwards. you do see a signal at 16 kHz; it’s the vertical line descending from the “16000” and that line represents the energy at that frequency over time (represented by the position on that line, the closer to the middle of the display the closer to “now” ). This is not a “16 Hz sound” it is a radio signal at 16,000 Hz and the modulation of the signal is just on/off, sufficient to send a Morse code signal (usually called “continuous wave” or CW modulation). The sound on the video appears to be a narrow bandwidth, about 200 Hz, centred on the 16,000 Hz signal; this is represented by the shaded area adjacent to and above the 16000 on the screenshot. I can hear the Morse on the signal, but not clearly enough to decode it, but then my hearing is not what it used to be :slight_smile: The source (an analouge record) is an audio recording (i.e. pressure waves in air) and the radio station is transmitting electromagnetic waves but many things could detect the signal unintentionally and it would find it’s way onto the record. Mechanical elements in the microphones, or guitar pickups are examples of such things… It will get in through AC lines as well… power supply components such as transformers and chokes will reduce 16 kHz interference but not eliminate it.
EDIT: oh yeah, I agree it’s obnoxious :slight_smile: I think this is meant to be of interest to keeners, not the rest of us. an interesting “application” of waterfall displays is people prank operating radio stations (usually numbers station or interlopers) by transmitting varying amplitude vs frequency across the passband of the signal (perhaps 6 kHz) in such a way as to generate an image in a waterfall display. Here’s an example:Pirates Spammed an Infamous Soviet Short-wave Radio Station with Memes

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Thanks to @babVU98i and @David_Guilbeaul for the detailed answers to my question!

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this is somewhat similar to Kodak detecting the a-bomb tests

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Given a large enough room, a big enough subwoofer and a loud enough signal, you can feel 16 Hz. This gets expensive quickly.

Chiefly of interest to organ music buffs.

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We’re in the 16 kilohertz range here. We’re talking tweeters, not woofers.

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“organ music” being the response of your organs to a loud 16 Hz tone? /s

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BTW, if you’ve only heard the tiny bit of Tubular Bells used for the movie theme, you haven’t actually heard the tubular bells. There is so much more going on!

Listen to the album for some great music, which in the end rises with somewhat goofy and quite endearing exuberance as Oldfield Vivian Stanshall* announces each instrument as it comes into the mix, until the climactic ringing of the

TU-bular BELLS!

*updated to correct the name of the person doing the voiceover, with thanks to @catsidhe for pointing that out

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That’s the first part.
The second part of the album ends with ‘Popeye’s Theme’…
Not sure what it is actually called, but it’s the last several minutes of the album.
I had that album, & from what I remember of the liner notes, he played every instrument & added them on to a master tape… which eventually wore out from all the overdubs & he had to do it all again. Apparently it went quicker the second time around.

I preferred his third album:

YMMV

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That wasn’t Mike. The voiceover was Vivian Stanshall from the Bonzo Dog Doo-Dah Band.

That was Ommadawn.

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And this is why analog rules.

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Right you are.
Memory plays tricks after 40+ years… I enjoyed both albums, though.

Viv Stanshall: “…and Nuclear…SUB”

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I never knew it wasn’t Oldfield doing the voiceover! Thanks for the knowledge. :slight_smile:

Ommadawn is also a favorite of mine, though it’s linked now with memories of a rather unfortunate breakup so I have to skip the bit about horses or I’ll start crying.

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