Earthquakes And Ionospheric Noises On CD

dpbsmith writes "Nerds will herald the re-release of a remarkable recording from the fifties: "Out Of This World," a twofer comprising "Earthquakes Around the World" and "Ionospheric Swishes, Whistlers, Tweeks; The Dawn Chorus." Smithsonian Folkways, in addition to the Folkways titles, also acquired the Cook Laboratories "Road Recordings" series. For a reasonable fee they will burn and send you a nicely labeled and packaged CD-R of any of the recordings in their catalog." Read on for a description of some of the interesting audio now available.

"Among the Cook recordings, not listed in their online catalog but available nonetheless (telephone 1-888-FOLKWAYS) is Cook Laboratories Catalog Number 5012. The Smithsonian's internal listing calls it simply "Earthquake," but it is actually a full transcription "Out of This World," with earthquakes on a 20-minute-long track 1 and ionospheric noises on a 20-minute-long track 2.

"Earthquake" is not an audio recording of the actual sounds that would be heard by a human being on an earthquake site. It is more cerebral than that.

In the 1950s, Hugo Benioff of CalTech devised a seismometer that recorded seismometer data on analog tape at a speed of 0.02 inches per second. The "Earthquakes" side delivers of the results of playing these tapes at standard playback speeds, speeding them up by factors of 187 to 750 times normal speed and converting subsonic earthquake vibrations into audible sound. The results are intriguing, indescribable, and curious to hear. Nearby earthquakes have a fairly sharp and brittle sound; distant ones sound dull and echoey.

The original LP contains a very strange track in which an earthquake recording is reproduced "to within 2 or 3 times original speed" and at a high amplitude. The narration notes that you will not be able to hear much of anything, but if you bend over and watch the tonearm you will be able to see it move. In fact, few tonearms, apparently including the one used by the Smithsonian to transcribe this segment, are able to play this band without skipping grooves.

The second side of the LP, "Sounds from the ionosphere," records the sounds that are heard when an antenna, with its signal suitably filtered, is connected to an amplifier rather than to a radio receiving set. The propagation characteristics of the ionosphere cause different audio frequencies to propagate at different speeds. The result is that the impulse created by a static discharge is heard, not as a click, but as a descending or ascending whistle. The sounds on this recordings are strange, melodious--almost like a mass of birds or spring peepers--and literally unearthly.

(If the ionospheric noises on Cook catalog #5012 are not enough, the Smithsonian also has Cook catalog #5013. This is a stereo recording combining ionospheric noises recorded simultaneously in Hanover, NH and Washington, D. C.)"

what about musci LPs

[Anonymous Coward]

I wonder if there are any coincedents out there where one could examine music record wax recordings from the 20's and detect distant earthquakes that the engineers never noticed.

Re:what about musci LPs

[fyonn]

there is, I'm sure, a famous recording of a classical peice recorded in one of the big london concert halls and if you've got good listening kit, in the quieted patches, you can hear the low frequency noises from tube trains on the nearby london underground.

I'd love to find you a link but I'm not quite sure what to search for while not gettig hits on the latest frech urbans hits from the london underground scene etc :)

dave

Pygmies of the Ituri Rainforest

[rodentia]

Among Folkways highlights is this highly regarded collection of field recordings of traditional songs of the Mbuti Pygmies. (Quiet, in the back there.) Crazy multi-voiced harmony and polyrhythm which stands out as among the oldest surviving human cultural achievements.

how ionospheric noise comes about

[sdedeo]

You can read all about it in Jackson's Classical Electrodynamics. Whistlers are quite beautiful; I first heard them when I started listening to shortwave radio.

The ionosphere is a plasma: it is made up of electrons and protons that are sufficiently diffuse that they spend most of their time unbound from each other (incident radiation keeps ionizing atoms; once their ionized, the two particles have a great deal of trouble finding each other.)

Because light waves are just propagating electric and magnetic fields, they interact with charged particles. In solids (and most gases, where the electrons are bound), they don't really "see" the charge: the electrons are very close to the protons and the configuration "looks" neutral. It is only at very shortwavelength that the light can "discover" that these atoms aren't neutral, but have, rather, two charged components. In plasmas, where the electrons and protons are very far apart, much longer wavelength -- radio -- waves discover this fact.

The particular density and temperature of the plasma defines a resonant frequency. Near this resonance, the radio waves have difficulty propagating: they start to interact strongly with the medium. Roughly (OK, very roughly) speaking, the stronger the interaction, the faster the radio wave propagates.

But wait! I thought light travelled at a constant speed regardless of wavelength! Well, yes, in vacuo. Here, because of the interactions with the plasma, all frequencies of interest are slowed down. Off-resonant frequencies are slowed more, because the plasma moves about in response to the fields of the light wave to partly cancel the wavefront (imagine trying to send a pressure wave through silly putty.)

The whistler comes about when you pump a large spectrum of radio frequencies into the ionosphere from something like a thunderclap. These waves then start travelling over the Earth. The higher frequency waves are closer to the resonant frequency of the ionosphere plasma, and so get to you sooner. You literally have to wait for the lower frequency waves to arrive.

The plasma is sufficiently ''dispersive'' that, for average ionosphere conditions, the lowest and highest frequency waves will be 10,000 km apart. A pretty large musical instrument!

A final, neat point: while the whistlers are somewhat like a prisoner tapping on a radiator pipe, you can under certain circumstances get enough energy into the ultra-long wavelength modes to get a cavity resonance (make the Earth's ionosphere ring like a bell.) Could it be? Yes, indeed: this cavity resonance is detected after the detonantion of nuclear bomb (the EMP provides the lightning strike.)

Re:how ionospheric noise comes about

[jplanet]

And if you're interested in learning more about VLF or hearing whistlers and such for yourself, you can get a receiver here: http://image.gsfc.nasa.gov/poetry/inspire/

Re:how ionospheric noise comes about

[jplanet]

Sorry about that--here's the link

Inspire project [nasa.gov]

Re:how ionospheric noise comes about

[Anonymous Coward]

Good info, I only have one issue. When you say the 'stronger the interaction, the faster the radio wave propagates', I assume you mean the phase speed of the wave and not the group velocity. The group velocity (which carries the energy of the wave and therefore all the information about the wave) travels slower than in a vacuum.

Re:how ionospheric noise comes about

[sdedeo]

I am talking here about the group velocity. All plasma waves have a group velocity slower than the speed of light in vacuum; it is the difference in group velocity between different frequencies that leads to the whistler effect. (In this regieme, the phase and group velocities happen to be roughly proportional.)

Expensive!

[orthogonal]

For a reasonable fee [Smithsonian Folkways] will burn and send you a nicely labeled and packaged CD-R of any of the recordings in their catalog

Folkways is a legendary label, and I'm happy to say I have a few Fokways CDs (Woody Guthrie -- and given the present administration, I appreciate all the more "I Dreamed I Saw Joe Hill").

I'd love to buy more, but frankly, at 19.95 for CDR, it's a bit pricier than I can bear, especially considering that the CDRs being copies the original albums that predate the LP -- Long Playing album --, tend to be brief.

I'd rather see my money go to the Smithsonian that to RIIA plutocrats any day, so I wish they could find a better price point. At $5 per album, they'd see a lot of business form me. At $10, I'd be willing to take a chance, given Folkways's reputation. At $20 per, I have to consider saving three bucks and getting a two-CD Gilbert & Sullivan opera at 78s2CD [78s2cd.com].

weee

[Pumpernickle]

Boomboxes: check.
Car speaker volume on high: check.
Subwoofers installed: check.
Subwooofers operational: check.
Earthquake recording: check.
Target in sight....
Turning on....

*RUMBLE*

No more cheap rap stuff like those guys at school have. And they thought what they had was cool... :P

Yes but...

[El]

can you dance to it?

Wow! A Blast from the Past!

[Anonymous Codger]

My father had this recording when I was growing up in the '50s. A very weird listen, especially for that era. I guess I'll have to shell out just for the nostalgia value.

Now that my memories have kicked in, I'll also have to try to track down a recording called "Bull in a Chime Shop", which was a bizarre all-percussion ensemble. This LP would cause all the neighbors to close their windows and cower under their beds.

The '50s were the golden age of Hi Fidelity. Tubes ruled, small Hi-Fi shops were like temples, and the shelves were full of recordings intended purely to show off the quality of your equipment.

Re: Bull in a Chime Shop: good news

[dpbsmith]

Yes! Yes! And I thought I was the only person who had ever heard that record.

The title was actually "Speed the Parting Guest" and yes, indeed, the Smithsonian has it, too. Cook catalog number 01041. It is paired with an even weirder recording called "The Hot-Tempered Clavichord," of a jazz pianist playing a clavichord.

My copy of the Smithsonian had the tracks mis-numbered in the printed insert, and it appeared as if some of the tracks from "Speed the Parting Guest" were missing, but in fact they are all t

Re: Bull in a Chime Shop: good news

[Anonymous Codger]

Thanks - I did find this by googling up the full name and then found it in the Cook catalog. I didn't remember that it was a Cook production. Mr. Cook was quite prolific!

A few other items in the catalog looked familiar - I think my late father must have had a number of them. I sure wish my mother hadn't gotten rid of the LP collection when she retired and moved away.

More info and the Cook catalog

[Anonymous Codger]

I googled a bit and came up with a brief profile of Emory Cook and the complete catalog of his recordings, including the earthquake album, at the Folkways site [si.edu].

Giant Theremin...

[w3weasel]

an antenna, with its signal suitably filtered, is connected to an amplifier

I might be interested to hear this... but only if good 'ol mother Earth can play this giant theremin better than people can!
theremin noise can be violently irritating

Another nifty: Bell Labs "The Science of Sound"

[dpbsmith]

One more oldie-but-goodie from Smithsonian... this one from the Folkways catalog rather than the Cook catalog... is "The Science of Sound," Folkways 06007. Their online catalog is confusing... the original 1958 recording was a two-LP set and Smithsonian's Folkways 06007 appears to be the full recording; there is also another entry under the same title that seems to be only a portion of it.

Anyway.

This was a tutorial produced by Bell Labs which has dozens of sonic examples of the effects of filtering out high and low frequencies, overtones, "subjective tones," and so forth and so on. All accompanied by fifties-style authority-figure Edward-R-Murrow type narration...

Re:Another nifty: Bell Labs "The Science of Sound"

[coyotegestalt]

Yes, a wonderful tape- I use it frequently at work for our "Sounds of Science" shows (part of the university physics department's community outreach program [umd.edu]). The narrator was Phillip Tonken. I think he was with WOR-AM back in the 1950s and 60s, and did narration for radio shows like "Dantro, The Planet Man" and "Murder by Experts."

A CD not in their catalog

[weeboo0104]

Here is a CD [mrmethane.com] of "atmospheric noises" that I didn't see in their catalog.

Sounds of the Northern Lights

[Chatmag]

Something along the same lines, NPR had a series called Lost and Found Sounds, with recordings of the Northern Lights [npr.org]