MANUAL OF ANALOGUE SOUND RESTORATION ... - British Library

Preface
With the rapid pace of change in audio technology, analogue formats have all but disappeared as
a means for current production and distribution of sound recordings. Nevertheless, many audio
archivists are responsible for large numbers of valuable audio recordings in analogue formats.
These require dedicated playback machines that have become obsolete, so the only way to ensure
lasting access to this legacy is digitisation. To do this properly requires firstly that the optimum
signal is extracted during playback from an analogue carrier, and this in turn necessitates extensive
knowledge of the engineering processes and standards used at the time of its creation. The
passing on of expertise and detailed knowledge gained during a time when analogue technology
represented the cutting edge, is therefore of vital importance to subsequent generations, and it is
with this in mind that this work was written.
The manual was written by Peter Copeland when he was Conservation Manager at the
British Library Sound Archive over a ten-year period up until 2002, as an aid to audio engineers
and audio archivists. Peter started his professional career at the BBC in 1961, initially working from
Bush House in London for the World Service. From 1966 he worked as a dubbing engineer at BBC
Bristol, taking on responsibility for sound in many productions by the famed Natural History Unit,
among them the groundbreaking David Attenborough series, Life on Earth. In 1986 he joined
the British Library as Conservation Manager for the Sound Archive where he started work on this
manual. After Peter retired from the Library in 2002, we began work with him to polish the text
ready for publication. The work was near to completion when Peter died in July 2006.
The original intention was to thoroughly edit the manual to bring it up to date, with
appropriate diagrams and other illustrations added. However in the extremely fast-moving world
of audiovisual archiving this would have entailed a great deal of rewriting, such that it would no
longer have been the manuscript that Peter left us. After much discussion therefore, the decision
has been taken to publish it now, largely unchanged from its original form, and make it freely
available on the internet as a service to professional audiovisual engineers and archivists.
Readers should bear in mind that the manual was written over a period of time some years
ago, and so should be considered as a snapshot of Peter’s perspective during that time. Some
information, particularly on digital conversion in chapter 3, is outdated: the R-DAT format is now
obsolete, professional audio engineers routinely use computer-based hardware and software for
audio processing with 24-bit converters at sample rates exceeding 96kHz, and sigma delta
processors are now available. The core of the manual however, being concerned with making
sense of the incredibly rich and complex history of analogue technology, remains a singular feat of
rigorous, sustained research, and is unlikely to date. Some statements in the text represent
personal opinion, although this is always clearly stated. The somewhat quirky, personal style in
which the manual is written will be very familiar to anyone who knew Peter, and was as much a
part of him as was his passion for the subject of this work. Minor amendments to the original
texts have been made, mostly ironing out inconsistencies in style and for this I would like to thank
Christine Adams, Nigel Bewley, Bill Lowry, Will Prentice, Andrew Pearson and Tom Ruane who
helped check through the manual in its entirety.
This work assembles in one place a tremendous amount of factual information amassed
during Peter’s long career as an audio engineer - information that is difficult to find anywhere
else. The breadth of research into the history of sound playback is unequalled. Peter himself
sometimes referred to his role as that of an “audio archaeologist”. This manual is a fitting and
lasting testament to Peter’s combination of depth of knowledge with clarity of expression.
1
Richard Ranft
The British Library Sound Archive
September 2008