From the Higgs Boson Particle to Leadbelly 194
Roland Piquepaille writes "Physicists from the Lawrence Berkeley National Laboratory are using the same methods to search for the elusive Higgs Boson particle and to digitally restore audio recordings from the past. Berkeley Lab signed an agreement with the Library of Congress to digitize the many thousands of early blues or jazz recordings it has in its archives. And the results are spectacular. Compare for example, these two versions of "Good Bye Irene", before and after being optically reconstructed (WAV format, 18 and 19 seconds). This news release describes the method used by the physicists. This overview contains other details and extra references about this project." We also covered finding Higgs Boson recently as well.
Sheesh - All Around Wrong (Score:5, Informative)
2). It's "Good Night Irene"
Mirror of WAV (Score:2, Informative)
Sure it'll be slashdoted soon.
Orignal [netspace.net.au] & Digital version [netspace.net.au]
Digital Needle (Score:5, Informative)
Re:quality loss (Score:4, Informative)
big news (Score:5, Informative)
They also emphasized about how they wanted digital version of the original recording, with all of the noise, clicks, and dropouts intact. After all, they are digitally archiving what they have, not restoring it.
One of the biggest finds was an original recording of "This Land is Your Land" by Woody Guthrie with the following stanza intact:
Was a big high wall there that tried to stop me,
Was a great big sign that said, "Private Property,"
But on the other side, it didn't say nothing,
That side was made for you and me.
I believe it's a one-of-a-kind and it was found on accident, as the archives literally have dozens of different "This Land is Your Land" recordings and it had previously been digitized before this version was found.
RIAA Equalization (Score:5, Informative)
Back in the good old days of vinyl records, RIAA Equalization [wikipedia.org] was/is an industry standard for how music that is recorded on vinyl records is played back. The idea is to compensate for the fact that vinyl does not have a flat audio frequncy response.
The link above explains it much better (and in more detail) that I can.
\/Don
Re:Sheesh - All Around Wrong (Score:5, Informative)
No it's not. His surname was Ledbetter, but his nickname was Leadbelly. More info about his life can be found here [duke.edu]. If you still think it's Ledbelly, look at the photo of his gravestone at the bottom of the page.
If there are any slashdotters who don't know who the hell he is, you might know at least one song he wrote : Where did you sleep last night which was sung by Nirvana on MTV Unplugged
A little info re: that LoC collection (Score:5, Informative)
There are some well-known LoC recordings that have gained some fame, including a series of recordings by Leadbelly and an awesome set of music and reminiscences by Jelly Roll Morton. However, both those sets were recorded "in studio" and are not field recordings. They are magnificent though.
Btw, I should make special mention of the Lomax family. Father John and son Alan were responsible for some remarkable recordings, including the work by Leadbelly and Jelly Roll. Alan also made the earliest recordings of Muddy Waters and some excellent recordings of Son House while working for the LoC. John was something of a Texas cracker (check out his dialog with Willie McTell on the LoC recordings), but he was a brave man going into some of the places he visited. He also wrote a very weird account of his acquaintance with Leadbelly in a book he wrote about the great self-proclaimed King of the 12-string Guitar..
Some of the catalog has been available to the public for quite a while, but I doubt that catalog has listed anything close to the amount of material the LoC must have in their vaults. Those acetate masters won't last forever, and I'm glad to learn that an attempt will be made to save those recordings.
Btw, I doubt copyright is an issue with this material. Unless I'm mistaken I believe all of it is in the public domain now. Perhaps someone else can clarify ?
No recent US administration would dream of doing such a project now. They definitely would *not* want to do it to know the collective mind of the people...
Re:big news (Score:3, Informative)
It's not a one of a kind, in the sense that the folk music community has known all along about Woody's alternative lyrics to the song. In fact Woody wrote several additional verses, as this link [geocities.com] shows. Considering the state of politics back in the 1950's and 1960's, it's not surprising that these lyrics were not widely published (or performed). In fact, I know of some musicians in my own community today who refuse to sing these verses because of concern that they would offend some members of the audience.
Re:Why WAV? (Score:3, Informative)
This is important work (Score:4, Informative)
I am a big fan of early blues. My favourites are Leadbelly, Blind Lemon Jefferson and Robert Jordan
Indecently, Robert Jordan is the guy who supposedly sold his soul to the devil one night at the crossroads in exchange for his guitar playing skills. This story gave rise to the whole blues, rock etc. comes from the devil story.
You can find a lot of their music on p2p networks - it's worth checking out. You'll be surprised how many songs you recognise - they have been copied and covered so many times.
Only Step One (Score:3, Informative)
A complete restoration would compensate for the transfer functions of the microphone and other recording equipment used for the particular recording. Need to archive and preserve all the recording equipment also!
Re:This is important work (Score:3, Informative)
Robert Johnson was an innovator of blues guitar and did lots of things like open tunings. Many musicians try to immitate him. Some are successful and most are not. Robert Johnson's style of blues is still unique today, because of how he sang, tapped his feat and played the guitar.
Re:Sheesh - All Around Wrong (Score:3, Informative)
Re:Sheesh - All Around Wrong (Score:5, Informative)
But perhaps the most telling Leadbelly song is about the time when Huddie Ledbetter, beter known as Leadbelly, came to Washington D.C. to record for Library of Congress's Archive of American Folk Song.
Huddie and Alan Lomax were denied accomodation at several hotels because the hotels wouldn't rent to an interracial group: Huddie was black and Lomax, co-founder with his father of the Library's Archive, and, was white.
So Huddie, with Lomax's help, wrote "Bourgeois Blues", which begins:
Huddie's gone now, and Alan Lomax died two tears ago, but the song, and their work, live on.
And even after desegregtion, Washington D.C.'s still a bourgeois town, it's a bourgeois town.
Th eRIAA response (Score:2, Informative)
Basically, it involves the master being equalised with the bass rolled-off by (up to 20dB) and the treble boosted by a similar amount. On playback, the 'phono' input on your amplifier ampplies inverse EQ to re-create the original signal.
The reasons are two-fold:
The initial treble emphasis followed by roll-off reduces the contribution of record surface noise from the mechanical transcribing.
The bass rolloff means that the excurions required by the cutter (and the sylus in playback) are kept within reasonable limits - and enable closer groove spacing, allowing a useful recording time. Note there's a direct tradeoff in LP mastering between playback time per side and sound quality, depending on how 'hot' the signal to be cut - more groove excursion requires more space.
The RIAA's contribution was to declare a standard for the EQ curves, when before c.1948 each record company would do more-or-less its own thing.
Re:I still hear static (Score:2, Informative)
We did this in a signal processing project, where we scanned old recordings and extracted the music. We tried Wiener fitlerning, but settled on spectral subtraction. Listen in [s3.kth.se]. The problem is (as an anonymous coward so wisely pointed out) that you inevitably remove some of the wanted signal as well.
Re:Sheesh - All Around Wrong (Score:5, Informative)
This mixing and changing of songs is and has been very common. The urge to be authoritative is very strong, but you ought to avoid it here. I have read Ledbelly, Lead Belly and Leadbelly without finding any truly convincing arguments about which is correct. Did he carry around buckshot in his belly? Was it just from Ledbetter? I do not know. With unwritten traditions, the roads often just peter out without leading anywhere conclusive.
Re:Star Trek (Score:3, Informative)
Spectral revelations about the result sound (Score:5, Informative)
Result sound viewed with -42 threshold [princeton.edu]
Result sound viewed with -60 threshold [princeton.edu]
Result sound viewed with -42 threshold [princeton.edu]
And the following image is a spectrogram of the original "Goodbye Irene" file:
Original sound viewed with -42 threshold [princeton.edu]
Each of these spectrograms was computed using 1024 point Discrete Fourier Transforms with a factor of 8 overlap. The dimensions of the images are unlabeled, but provide a frequency range of 0Hz - 22050Hz along the vertical axis, and approximately 344 horizontal pixels represent one second of time. Darkness represents the magnitude of the signal at a particular measured frequency.
With significant interest, I can perhaps label these axes for easier reading. Simply keep in mind that the top of the vertical dimension represents 22050 Hz.
Given the sound quality of the result sound provided, utilizing 16-bit quantization with a sampling rate of 44.1Khz is more than adequate. But while the result is promising, it is hardly archival quality in my opinion, due to the obvious digital artifacts.
The dynamic range of this particular music is confined by musical convention and the microphone technology available for the recording. The theoretical 96dB of dynamic range availed by 16-bit quantization is more than sufficient to represent the dynamic range of this particular music (and many others) recorded with similarly early microphony and disc-cutting technology.
The frequency range of the music does not appear (in this result mind you) to have significant musical information above an approximate (but conservative) 11000 Hz. The frequency range availed by a sampling frequency of 44.1 KHz is more than adequate to quite faithfully represent this music. To significantly reduce the broadband pops and crackles in the recording, high frequency information is lost. Further, the recording technology available at the time probably could not accurately transduce such frequencies from the original performance either.
The spectrogram reveals that the undulating noise in the result sound occurs at a nearly precise 5Hz. It also reveals that this "noise" is obviously an artifact of the restoration process; it really isn't noise, but the result of a time-varying filter which cuts gaussian lobes into the spectrum of the music from approximately 4000Hz to 9200Hz in a manner somewhat a kin to a wah wah pedal. The lobes can be seen clearly in all of the spectrograms I provided, but they appear more stark as the peak threshold of the spectral plots decrease. Their duration is quite close to .05 seconds.
In my opinion, archives should preserve physical recording media as long as possible to allow transduction techniques to mature. I find the 5Hz filtering artifact present in this result to make the current state of this particular optical transduction process unacceptable for archiving. It would be a shame to replace physical media with music colored with such avoidable artifacts. I am sure that such artifacts can be alleviated and that optical scanning of phonograph records (discs and cylinders) has great promise as a transduction technique.
Do this yourself for only $10k (Score:2, Informative)
Pre-Phonograph Recordings (Score:2, Informative)
Re:Improved quality? (Score:2, Informative)