Irene Project

The ELP player remains the only commercially-available laser turntable, but other applications of the technology have emerged such as the IRENE (Image Reconstruct, Erase Noise Etc) System. The two systems differ, however, in that while ELP is wholly analogue, IRENE is based on digital technology.

Developed by physicist Carl Haber and installed in the US Library of Congress, IRENE is an 'Optical Scanner for Access and Restoration of Disc Records', and is a joint project by the Lawrence Berkeley National Laboratory and The Library of Congress that's being funded by the National Endowment for the Humanities, Library of Congress, Mellon Foundation, Guggenheim Foundation and the Department of Energy. Additional partners include The Phoebe Hearst Museum of Anthropology, The University of Chicago South Asia Library, The Berlin Phonogramm Archive, The Smithsonian Institution, the Edison National Historic Site, and the University of Applied Science.

The initial IRENE unit used a 2D camera rotating around the record which takes detailed digital photographs of the grooves. Software then interprets the digital images to reconstruct the recorded sound. IRENE often produces a large amount of hiss with the recording, but it is very capable of removing pops and clicks produced by scratches on the record surface. Following this, the 3D/PRISM (2009) project, funded by IMLS, focused on the extension of the IRENE approach to 3D imaging of cylinders and discs using confocal microscopy. These are not being developed for sale, but bespoke machines intended to recover historical recordings on early disc or cylinder media.

'Use optical measuring technology to create digital maps of the record surface, retouch image to repair damage, play with a 'virtual' needle,' says Haber. 'Techniques used to build instruments and analyse data in particle physics research were the inspiration for the approach applied here to audio.'

Laser limitations

Laser turntables are so thorough in their scrutiny of a recorded groove that they will pick up everything the groove contains – including alien deposits that have not properly been cleaned from the groove – not necessarily physical damage such as scratches. Some of this can be eliminated. In the case of the ELP device, records must be black; coloured, transparent or translucent records cannot be played, so laser's not good for bringing new life to your punk picture-disc or New Wave coloured vinyl collection. *

This is an updated version of the article that appeared in the December 2011 print edition of E&Tmagazine.

http://eandt.theiet.org/magazine/2011/11/lasers-get-groovy.cfm