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Was: arsclist reel to reel player/recorder
As is common in web discussions, this one has branched out.
Both lines are extremely relevant.
The present theme is "Digital Storage vs. Analogue Storage", and
responses (if any) should change the subject line.
I believe that the idea of transferring sonic content to another
medium should be seen with a perspective. The Technical
Committee of IASA is currently revising the technical
recommendation TC-03 entitled "The Safeguarding of the Audio
Heritage: Ethics, Principles and Preservation Strategy". In my
contribution to the work I have stressed that we both have the
intended content, the primary information, and ancillary content,
the secondary information. The primary information is what we
colloquially call "the recording", and obviously that is what we must
strive to reproduce as correctly as possible to obtain a signal which
may then be stored by digital means, with all the error correction
and cloning of signal that is possible in that domain. However, we
frequently cannot determine the primary information precisely
without having access to the secondary information and being
aware of it. The secondary information may be background sounds,
hum, certain distortions, rumble as well as separate materials
surrounding the primary information, such as tape boxes with
handwritten information, writing on lead-in tapes, colour codes, etc.
The primary information is quite naked, and source criticism as to
its proper use will have a hard time, briefly put, you may compare
performances, but you may find it difficult to establish the
circumstances that created the difference between two recordings.
If transparency in the recording-reproduction chain has been
obtained, then there is only description ("metadata") to provide a
check on contents. And since the description is human-generated,
it may also contain lies. Hence, authenticity of the original source
must be relied on, rather than determined by source criticism. If, on
the other hand, there is a lot of additional noises, then a lot of
ancillary, secondary information is present which has not been as
easy to tamper with, and responsible analysis may proceed.
Now, dividing the total signal content from a carrier into these two
completely different categories is in itself an artefact, it is a way to
look at things. The reason that I use it (it is an application of
Operational Conservation Theory) is that it forces an awareness of
what we are handling. In principle we destroy information
(secondary information) when we make a transfer to a digital
medium in which domain there is potential for eternal life (still-life).
There are many things which we cannot find out afterwards. If we
filter and noise-reduce, then those offending noises will not only
have gone (for immediate gratification), but long-term we will never
be able to use the qualities of these noises to increase our
knowledge about the primary signal.
Let us have a little cry over the fact that we cannot do the ideal
thing, and then move on!
In the real world we have three possibilities: to collect everything
and let wear, tear and environment do the selection for us, to
preserve as long as possible the medium and the machines for it
(the system), to transfer to a more durable system. If we are poor
we must make a selection ourselves. A number of years back, the
Danish Radio would preserve 7% of the output, selected with
breadth in mind. However, we cannot be sure if the future will have
the same concept of breadth as they had when the selection was
made. These 7% were (and are, I expect) guarded and protected
by re-copying programmes.
I will now express a heretic view which obviously cannot go into a
recommendation from an international organisation: we have to
indicate what must be regarded as best archiving practices,
something that activities in planning and carrying out daily archival
activities can be measured against. If these recommendations are
followed, we can be sure that the material thus handled will be
available to future users of all kinds. However - and this is the
heresy - the future users will in many cases desire a breadth which
widely surpasses that which has been selected out. I believe that
they will sacrifice quality for variation and breadth. In other words,
rather than spending time and effort on doing the best final transfer
before eternal life (analog generation of a signal which will be A/D-
converted), perhaps we should do mass digitisation without much
calibration, but with good indexing for later retrieval. The future user
will in a number of cases find distorted or ill-sounding sounds, but
they are still better than nothing! And (a worse heresy coming up!):
a data reduced (physiological data reduction) signal which the ear
perceives as sound, but which has had all its statistics destroyed
*is still better than nothing at all*. Not all the future queries to the
material are of the type "can we determine if a female voice
belongs to a nervous person by means of the power spectrum of
her utterance "ouch"".
So, to sum up, the heretical view is "bad sound is better than no
sound at all".
Now for a visualisation of what 16 bit, 44.1 kHz really means:
"This means that the amplitude can linearly assume + or - 32565
different sizes (sic!) If we suppose that our eyes are extremely
sharp, we could draw lines of a hair's breadth, namely 0.01 mm.
With the same graphic resolution, a signal of 1 sec duration could
be drawin along a time axis with a length of about 45 cm. Similarly,
the range of amplitude covers a length of approximately 70 cm. A
graphic presentation like this requires a sheet of A2 size [GBN
note: this is similar to 4 sheets of letter-sized paper]. This will
suffice to show that even the representation of the processed date
is highly problematic, let alone their survey."
The above is a quote from: Istvan Pintér: "Sound Microscopy and
Music in the 20th Century. A Survey with Special Reference to
Hungary", in "I sing the Body Electric", Ed. Hans-Joachim Braun,
Wolke, Hofheim 2000 (pp. 135-147). This is a book that I have
reviewed for the IASA Journal.
The above precision shows what Art Shifrin is aiming for when he
draws waveshapes.
Archiving philosophies are good, not because they get the job
done, but because they create awareness about our goals and
responsibilities.
Kind regards,
George Brock-Nannestad
Preservation Tactics