interesting links for vinyl physics

-  http://www.vinylrecorder.com/stereo.html illustrates stereo groove modulation.  While vertical and lateral modulation were both used for 78rpm mono, lateral modulation became the standard because of groove durability and the fact that large amplitudes of vertical modulation would virtually eliminate the groove.  Instead of implementing stereo with vertical/lateral, problem of vertical avoided by compromising both sidewalls to modulate at 45deg, phase-shifted 180.
-  http://en.wikipedia.org/wiki/Gramophone_record wikipedia article, great overall picture from history to materials and manufacturing
-  http://www.aardvarkmastering.com/riaa.htm RIAA dimensions and standards
-  http://www.euronet.nl/~mgw/background/riaa/uk_riaa_background_1.html RIAA equalization graphs
-  http://eil.com/explore/guide/vinyl_making.asp great background info on cutting vinyl master discs to manufacturing stampers
-  http://www.vestax.com/v/products/recorders/vrx2000.html (Vinyl lathe, ~$10,000 USD), http://www.vinylrecorder.com/order.html (Vinyl lathe, ~$4000 euro)
-  http://www.music.mcgill.ca/~deleon/courses_files/mumt611_files/mumt611_a6_deleons.pdf my presentation on image to audio conversion for MUMT611, an overview of its current state as of April 2006
-  http://www-cdf.lbl.gov/%7Eav/ LBNL sound reproduction page containing movies, audio, and papers of Fadeyev and Haber's work for wax cylinders