Convention Paper
Equalisation for Archival Transfer: In the Analogue or the Digital Domain?
AES Convention 112 · Paper 5534 · April 2002
Abstract
Equalisation for Archival Transfer: In the Analogue or the Digital Domain? S.W. Davies. Abstract. Most analogue recordings have deliberate departures from a level frequency response and these were made with the assumption that they would be equalised on playback, either through published data specifying the appropriate curve or throyugh the provision of specialised hardware. This paper examines the possible choices and their implications vis-a-vis performing these equalisations prior to or post the analogue / digital conversion. We consider two main categories: 1) Stationary curves such as RIAA for disc, IEC and NAB for tape and 2) Non stationary curves such as noise reduction systems by Dolby, EMT, dbx. In addition to the purely technical trade-offs consideration is also given to the demands on the knowledge of the transfer engineer and the ability of the chosen method(s) to compensate either instantaneously or subsequently for erroneous decisions made at the time of transfer.
