How does Shazam recognize music? Christophe Kalenzaga sifts through an old research paper (pdf) by Shazam's founder and conducts a short (written) course in signal processing, acoustics, Fourier transformations, and fingerprinting music. [more inside]
The BBC reports that the last typewriter to be built in the UK (according to its manufacturers) has been donated to London's Science Museum. "Brother said it had stopped making typewriters because demand had fallen to 30 a day, with most of those being sold in the US." [more inside]
Towards the end of the 1800s, there were three primary American groups competing to invent technology to record and play back audio. Alexander Graham Bell worked with with Charles Sumner Tainter and Chichester Bell in at their Volta Laboratory in Georgetown, Washington, D.C., while Thomas A. Edison worked from his Menlo Park facilities, and Emile Berliner worked in his independent laboratory in his home. To secure the rights to their inventions, the three groups sent samples of their work to the Smithsonian. These recordings became part of the permanent collections, now consisting of 400 of the earliest audio recordings ever made. But knowledge of their contents was limited to old, short descriptions, as the rubber, beeswax, glass, tin foil and brass recording media are fragile, and playback devices might damage the recordings, if such working devices are even available. That is, until a collaborative project with the Library of Congress and Lawrence Berkeley National Laboratory came together to make 2D and 3D optical scanners, capable of visually recording the patterns marked on discs and cylinders, respectively. [more inside]
The contraption was "created from a mishmash of lenses and computer parts and an old Super 8 movie camera." It was the size of a toaster, ran off "sixteen nickel cadmium batteries, a highly temperamental new type of CCD imaging area array, an a/d converter implementation stolen from a digital voltmeter" and took 23 seconds to record an image to cassette tape. But when Steve Sasson and his team of Kodak technicians presented the world's first digital camera to the public in 1975, they were asked: 'Why would anyone ever want to view his or her pictures on a TV?' [more inside]
What is the relationship between the optical groove in a record or wax cylinder and sound, and how can we use this to recover analog recordings from the past? Dr. Carl Haber explains IRENE (.pdf; begin at slide 44 for audio samples).
How to convert LPs to CDs. Many audiophiles will mock the software they suggest using as well as the hardware pictured, but this is aimed for the everyday people that don't have a laser turntable or ProTools. All in all, a decent introductory guide.