ARSC Conference 2016
Review: ARSC Conference
Bloomington/USA, May 11th - 14th
At this years' 50th annual ARSC conference, Peter Kuhnle, CTO of NOA, presented his paper on "Digital De-emphasis Filters in Gramophone Recording Digitisation" to an audience of internationally reknown specialists in audio preservation. Asides from interesting discussions around this and other topics of AV preservation, we were excited to visit Indiana University's MDPI project on the campus, where NOA client Memnon Archiving Services made the greatest contribution to reach the current status of more than 95.000 audio carriers digitized since project start in summer 2015.
In his paper, Peter Kuhnle describes principles and application of digital de-emphasis, re-emphasis, and cross-emphasis in gramophone recordings - especially for pre-1954, non-standardized records. Using digital de-emphasis filters instead of analog circuits provides several advantages. Digital filters are free of component tolerance. With their parameters documented, de-emphasis processing is completely reversible. Thus the handling of dual, filtered and unfiltered versions becomes obsolete, leading to simplified workflows, where not two, but only one audible preservation file including de-emphasis metadata can be stored in the archive. In combination with high-quality linear pre-amplifiers and A/D converters, gramophone digitization in surpassing quality may be realized.
Digital de-emphasis will be available in NOARecord's latest release.