Colloquium Seminar Announcement Dr. Vitaliy Fadeyev Lawrence Berkeley Laboratory "Audio Reconstruction of Mechanically Recorded Sound by Digital Processing of Metrological Data" Date: Monday, May 23, 2005 55 Roessler Time: 4:10 pm. Abstract: For the bulk of the recorded sound history the audio information was stored in mechanical media, such as a phonograph record or wax cylinder, via undulated surface incisions (grooves). The grooves shape and position can be reconstructed without mechanical contact by using precision optical metrology tools. The surface map thus obtained can be digitally processed to remove noise artifacts due to damage and wear, and to convert the groove positional information into audio format. The viability of this approach was demonstrated on a 78 rpm shellac disk using two dimensional image capture and analysis methods[1]. The present work expands on these results. A three dimensional reconstruction of mechanically recorded sound is reported. The surface of the source material, a wax cylinder, was scanned using confocal microscopy techniques and resulted in a faithful playback of the recorded information. The approach holds promise for careful reconstruction of valuable historical recording, using full surface information to improve the sound fidelity, as well as means of automated mass preservation. [1]Fadeyev V. and Haber, C., J. Audio Eng. Soc., vol. 51, no. 12, pp. 1172-1185 (2003 Dec.).

E-Mail: VAFadeyev@lbl.gov
Web Page: http://www-physics.lbl.gov/~fadeyev/