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audio digitization replies



Thanks to everyone who replied to my query regarding the
digitization of an oral history collection that is currently on reel-to-
reel analog tape.  We've decided to outsource it.  A few of you
noted that you'd be interested in any replies I received, so here you
are!

Replies to follow:

*****************************************************
Ms. Mosier

Personally, I would outsource the whole thing.  It would be less
hassle
on your end and the work would be guaranteed.  An audio engineer
will
also have a much easier go at it than a part-timer.  They would
have the
experience and the recording studio to do it.   I have done this work
before when I worked in a studio and the time it takes is
unbelievable.
You may still need to have a sound console as well as all the
computer
equipment and software.  There were occasions when I did have to
use our
Mackie 32x8 console.   Everything has to be played into the
computer in
real time.  Then you need to create all the regions in the software,
run
the noise reduction, adjust the volume, and burn the disc.  The
fastest
part of the whole process is burning the disc.  Even when I used
2x/4x
burner it was still the fastest part of the project.

I really like this idea for oral history projects.  It makes them much
more accessible.  I have been approached about doing this for one
of our
largest collections, but the cost was too much for the organization.
 I
have thought that maybe there was a grant proposal in there
somewhere,
but I need to investigate.

Miriam Meislik,MLS
Associate Archivist
Photograph Curator
Archives of Industrial Society
400 North Lexington Avenue
University of Pittsburgh
Pittsburgh, PA 15260
(412)244-7075 voice
(412)244-7077 fax
miriam@pitt.edu


Good Morning, I have been collecting data on a similar project,
digitizing
old video (from various formats) for preservation and access. The
main issue
I have identified is how much work needs to be done regarding the
subject
content. If it is a straight analog to digital conversion,  it is cheaper
to
outsource it, especially since most firms will give you a discount
for a
project of that size. If you believe some basic analysis of content
and
condition should be done, or hope to do some improvement to the
material, it
will probably be cheaper to do it in-house. At least here in Los
Angeles,
the rates for actually taking a look (or listen) to the material while
converting it are much higher than the rates for simple conversion.
Hope this is of some help.
Cheryl Miller

HISTORICAL ARCHIVE TECHNIQUES AND RATIONALE FOR
THE VOICES OF THE AIR &
SPACE MUSEUM AUDIO TAPE PROJECT
by Carl J. Bobrow
©2000


INTRODUCTION:

Broadly stated the goal of archiving is to preserve history, as it
survives
on paper, photographs, film, or as audio.  Each medium has its
own special
requirement with regard to preservation, conservation and
restoration.  The
need to maintain the historical integrity of archival material is the
basic
requirement of an archivist; it is also the prime justification for the
archive itself.  An archivist collects, maintains and provides access
to
materials contained within the collection.

It is the enduring access, dissemination and survivability of the
information, word, image or sound, which warrants the existence of
an
archival holding specifically for its evidential and informational value.
The rapid pace of new information technologies has been both a
benefactor
and a bane for the archive and archivist.  It has provided in some
cases
for better and easier conservation, restoration, access and storage.
 It
has also enlarged the scope and range of media to be preserved,
many of
which are technology dependent.  The problem is that to access
this
information specific equipment is required, which will eventually
become
obsolete.  The issue is a complex one with no simple solution;
other than
periodically to migrate the information onto new formats as required.

The audio archive has special requirements, simply because the
medium that
audio must invariably be stored on requires, in general, a more
complex
set-up of equipment than textual or photographic records require.
Audio
recordings can exist in either the analog or digital domain or both.
There
are a multitude of formats on which audio recordings can be found
on and
they are growing.  The medium can range from fragile wax
cylinders to any
one of number of types of analog and digital discs? recordings to a
variety
of analog and digital tape formats as well as a plethora exotic
media.

Analog magnetic tape has been the archival standard for many
years.  The
issue whether analog magnetic tape is the best medium for audio
archiving,
with long-term storage and eventual playback in mind, remains
unresolved.
There has been a general preference for both the media and format
since
they are robust and are highly standardized.  Since all magnetic
media is
far from being a permanent format for long term storage it has
come under
greater scrutiny as remaining the archival standard.  Within the
record
industry, for who the primary financial resources are a variety of
recorded
audio material, the standard medium and format of master tapes
has been
until recently analog magnetic tape.  There has been a major shift
in the
audio and record industry in recent years to the digital domain.

The question whether audio equipment manufactures will continue
to produce
analog tape recording gear has become a matter of serious debate.
 If the
current trend continues, and there is no reason to believe it will not,
we
can expect in the next few years the total cessation of analog
recording
equipment being fabricated.  If in fact that happens then the
industry will
no longer have the need to stockpile or produce replacement parts.
 The
lack of parts particularly for this type of equipment would make
them
obsolete in a short space of time.  The very nature of tape machine
mechanics makes them a high maintenance piece of equipment
because so many
of the transport components are either rubber or plastic based and
require
periodic replacement.  The record and playback tape head is
another high
maintenance piece, which requires either repair or replacement
almost as
often.

The implication is such that to continue to store archival audio
materials
on analog magnetic tape is ill advised.  What carrier then can be
confidently chosen to produce a long lasting archival recording?
The
question raises a number of issues such as, cost effectiveness,
sonic
quality, ease of use, durability, longevity or shelf life to name just a
few.  One of the many advantages of digital audio over that of
analog is
the high quality of reproduction that is available.  When properly
transferred digital media copies are clones of the master from
which they
have been duplicated.  This is an enticing and compelling choice
for the
use of digital recording for a number of reasons.  The first is the
ability
to transfer the stored data, in this case audio, without the inherent
loss
or added noise that is intrinsic when analog information is
duplicated.
This means as time goes on and new and better formats for
archival storage
develop the transfer of the audio image can be made without fear of
degradation.  Fu
rthermore, there can be multiple copies made which are
indistinguishable
from the original master, which would insure the highest quality
aural
perception to the listener.  Lastly there is the feasibility of
transferring information digitally from one locale to another via the
Internet.

How does one choose the best digital carrier or media?  Is there
one
optimal technology?  All digital magnetic tape media available fall
short
of the ideal since they too are intrinsically unstable.  The recordable
compact disc, or CD-R,  has proven to be a highly durable medium,
with a
calculated shelf life of 15 to 100 years depending on the type of dye
emulsion used in the manufacturing of the CD.  It is highly cost
effective,
in comparison to any magnetic tape format, both in the initial
outlay of
primary equipment as well as the media itself.  The record and
playback
process is a single standard universal format; the disc also offers a
simple and easy mode of operation that has a level of audio
excellence,
which is unparalleled.

Perhaps one of the most important tools available on CD?s in
general is the
search function and time indexing.  The unique geometry of the CD
facilitates a nearly instantaneous time indexing and search
function.  This
enables the user to locate and access any particular point on the
disk
without the need to move in a linear motion that is intrinsic with
tape.
On a tape transport this function can only be accomplished on
computer
assisted machines that have optical location tracking available and
the
tape must be wound forward or backward to reach the location
point desired.
All of which is tedious and time consuming.  Although from an
archival
standpoint this feature may not be as important as the question of
media?s
longevity, it is nonetheless significant with regards to its use as a
research tool.  Arguably the prohibitive cost of purchasing an auto-
locator
tape based machine coupled with the need for having a trained
archive
technician to run the unit along with the required upkeep and
maintenance
of su
ch equipment makes such operations limited to few institutions.  In
contrast the low cost and simpler use of a CD player can provide
easier and
greater access to materials contained within a collection.  Any disk
that
became unusable could easily enough be cloned from the master
copy thus
ensuring the ready accessibility to the material.

The imperfect nature of the CD-R as an archival format does not
exclude
either the importance of the media nor its potential.  In all CD?s
can be
viewed as a stop gap measure that will insures the preservation of
the
information already stored on another imperfect medium, whether it
is
magnetic tape, wire or records.  As already stated CD?s will permit
easier
accessibility, and better research tools and than tapes do in an
archival
situation.  Equally as important they also offer, for the future, the
ready
access and transfer to other digital media formats, this can be
achieved
without generational loss.  Something that analog copying cannot
ensure or
provide.


OVERVIEW OF THE NASM AUDIO TAPE PROJECT:

In 1994, the Aviation and Space Writers Foundation provided the
National
Air and Space Museum (NASM) with a $5,000 grant for the
proposed Audio Tape
Project.  The grant came as a result of an application Dr. Von
Hardesty, at
NASM, made to the Foundation.  His idea was to assemble under
one aegis the
scattered and endangered audio tapes, a unique historical resource,
existing in NASM?s holdings.  The three main objectives of the
project were
to archive the tapes, create a finding aid for the assembled
collection,
and to publish a book based on the unique material contained
within.

Dr. Von Hardesty was able to arrange with the Langley Theater, at
NASM, for
the transfer of their audio tape collection to the Aeronautics
department.
The Langley Theater tape collection contained audio recordings on
cassette
of lectures and seminars from 1976 to the present.  Don Lopez, the
deputy
director at NASM, provided additional audio tapes to the growing
aggregation as well.  Additionally, the NASM Archive also
possessed a large
collection of audio tapes that were in the possession of the late
Paul
Garber.  The NASM Archive was essential in evaluating this part of
the
holdings.  The remaining portion of the NASM audio tape collection
is
housed in Building 12 at the Garber Facility in Suitland Maryland.
The
tapes from Paul Garber were made before 1976, and consist of both
reel-to-reel and cassette tapes.  Alex Doster assisted Dr. Von
Hardesty by
providing information on the provenance of this collection.  Mr.
Doster
supplied a detailed commentary on how he had worked with a
number of people
in assemb
ling this older collection from the late 1960?s and 1970?s, which
was part
of the ?Brown Bag Lunches? series.

These audio tape collections are a unique historical resource that
spans
well over 40 years of lectures, interviews, speeches, and a wide
range of
symposia.  The breadth of speakers found in these collections is
unrivaled.
The subject matter covers a wide range of topics as well, dealing
with
almost every aspect of aviation, aeronautics, space history and
space
sciences.  Unfortunately, the funds received from the Foundation
would have
only provided for a small percentage of the material to be effectively
processed in the traditional archival manner.  The opportunity to
initiate
a new and innovative archive format using compact disc (CD)
technology was
examined.  With an extensive review by members of the museum
staff as well
as outside consultants, the practicability of such an approach was
considered tenable.

After a careful examination and review of the necessary equipment
required
the decision was made to obtain one CD recorder and two audio
tape cassette
recorders.  The initial procedure for archiving the tapes would
include
making a master copy onto an audio tape cassette as well as onto
CD.  After
the viability of recording to CD for archival purposes was
established, the
overall project and procedure would be re-examined and
recommendations
would be made to improve and possibly expand the project.

When the Langley Theater audio collection was first assembled, a
preliminary inventory was made, partly based on a printout from the
theater.  Other inventories existed, but there was no single
comprehensive
inventory of the NASM audio tape collection.  The preparation of
such a
catalogue, everyone agreed, would be an important initial step.
Preparation of a database file, one that could be updated
periodically was
initiated.  Nearly all the tapes were labeled so the task could be
completed without the need, at least, initially to listen to the tapes.
However, as the tapes were copied confirmation of the listing was
made.
Essentially, it is an enhanced inventory of the tapes in the
aggregated
collection.  The database was structured specifically with fields for
notes
on the program?s contents along with a listing of the tape format
and the
assigned number to both the original and master copies that were
made.
Recently the original nutshell database files have been migrated to
the
more sophisticated File M


aker-Pro dbase.  One of the essential elements of this program is
the
increased capacity of information that can be stored in each field.
This
valuable database will be the cornerstone for a comprehensive
finding-aid
for the burgeoning collection.

Complying with standard archival procedures all the media is now
being kept
in acid free boxes.  The original tapes and the duplicate back-up?s
are in
separate boxes.  The same is being done for the CD-R copies that
have been
made.  Each tape and CD is also in its own plastic ?jewel? case for
additional protection.

When the current project is completed the audio recording
equipment will be
turned over to the NASM Archives department.  Hopefully the
process will be
adopted in some form and additional tapes will be copied to the
digital
domain.


VOICES OF THE NATIONAL AIR AND SPACE MUSEUM:

As already stated, the Langley Theater at NASM has been the site
for a
number of lectures, seminars, and special events dealing with
various
aspects of aerospace history.  When the new NASM museum,
opened in 1976,
the Langley Theater began its long noted series of public events
attracting
an untold number of air enthusiasts to hear the reminiscences of
famed
pilots, aircraft designers, and aerospace figures.  Many of these
talks and
symposiums were preserved on audio cassette tapes.  For many
years this
unique collection of tapes were inaccessible to both scholars and
an
interested public.  With the Audio Tape Project, as described, now
underway
this situation will hopefully soon change.

One of the major components of the Project yet to be fulfilled will
be the
publication of a book based on material in the collection.  Voices of
the
National Air and Space Museum will be the first book based on the
Langley
Theater tapes.  The book will be devoted to the theme of military
aviation.
One of the unique aspects of the proposed book will be the
inclusion of
selected audio material, on CD, that will be extracted from the
collection.
Selected tapes have been identified to cover a number of key
historical
episodes and themes associated with air power.  The voices
contained in
these tapes either as lectures or seminar participants are
compelling
firsthand accounts of some of the pivotal events that shaped the
direction
of aviation history.

Some of the topics selected are as follows:
Battle of Britain, Airpower Over Dunkirk, Dam Busters (RAF), Night
Bombing
of Germany, Air Raid on Ploesti, Doolittle?s Tokyo Raid, Flying
Tigers,
Black Sheep Squadron, Testing Captured Luftwaffe Aircraft,
American and
German Fighter Pilots, Air Intelligence -- Germany and Japan,
American
Airmen POW Experiences, Aerial Reconnaissance, Tuskegee
Airmen, Women
Pilots in World War II, Chuck Yeager, Hanna Reitsch, and the
German ME-262


COMPACT DISC HISTORICAL AND TECHNICAL SYNOPSIS:

The 1970?s saw some important breakthroughs in digital audio
processing and
recording.  At the same time there were some major strides made
in laser
technology utilizing the new semi-conductor based systems.  As
the cost of
these technologies dropped, research into a new storage and
retrieval
system for digital data, one carried out by both Sony and Philips
independently, raced forward.  With the success of their respective
projects, in developing the laser disc and the compact digital disc
or CD,
it was quickly realized that there were a number of new markets
that would
be open to both manufactures.  In order to avoid the confusion of
two
different and competing platforms, a mutually agreed set of
standards was
developed for the new format.

One of the first industries to utilize this new format was the record
business.  With an industry wide desire to replace vinyl records and
develop a new format to showcase the expanding digital audio
domain the CD
was a perfect media.  The CD looked familiar, like a high tech 45,
yet it
was quite different.  The initial market though slow to grow would
inevitably exceed all the record sales and revenue from the past
decades.
In the early 1990?s, the recordable CD format would be initially
marketed
for both data and audio storage.  The overall cost reduction of
manufacturing enabled the production and sales of the CD recorder
and blank
discs to expand tremendously in the later part of the 1990?s.  In
1997
alone, nearly two million CD-R and CD-RW recorders were sold
along with an
amazing two hundred million discs.

The physical characteristic of a CD is Lilliputian considering the
data
storage capacity.  It is 120 millimeters (4.75 inches) wide and can
hold
680MB of digital data, or 74 minutes of stereo 16-bit, 44.1kHz
digital
audio.  The CD does not use an electrical or magnetic recording
technology,
but an optical recording method instead.  It works on the principle of
reflecting a laser light onto a receptive photosensor inside the CD
player.
The amount of light received by the photosensor allows the CD
player to
determine whether a particular area of the disc surface contains a
pit or a
land, and hence whether a digital binary 1 or 0 should be queued in
the
outgoing digital datastream.  These 1?s and 0?s are dynamically
interpreted
by a series of high speed digital processors and are turned into a
digital
data stream of information that are in turn processed by a digital to
analog converter, which then produces the analog audio output.

Pre-recorded CD?s are molded with these physical characteristics
(pits and
lands) inherent in their design.  A CD-R disc, on the other hand, is
molded
with a continuous pregroove for the laser to follow.  It is a WORM
disc
(Write Once Read Many), since once the data has been written to
the disc,
it cannot be removed.  CD-R?s are covered with photosensitive
organic dyes,
such as Cyanine, Phthalocyanine or Azo; similar to those used in
photography.  Lasers generate light with a precisely controlled
wavelength
with all its particle?s in-phase with each other.  This phenomenon
allows
for the accurate focusing of the beam.  A CD recorder uses a built
in laser
to alter minute areas of the dye on the disc surface, creating a
structure,
which, to the laser pick-up, emulates a pre-recorded CD.

The Orange and Red books, developed by Sony and Philips, define
the
standards required for different types of CD formats.  The Orange
Book
defines CD-Write Once formats and the Red Book defines CD-DA
(audio).
CD-R?s should conform to Part II of the Orange Book, a document
that lists
the specifications for CD-R technology.  This specifies not only the
physical size of the disc but also the characteristics used for
storing
information on the disc.  The audio CD attributes are described in a
similar way in the Red Book.

Because CD-R?s are coated with different recording dyes, there is a
difference in the varying life expectancies.  The current CD-R?s
used at
NASM are made with a Phthalocyanine dye which according to the
manufacturer
can hold data for an excess of 50 years, when properly stored.  The
archival life expectancy of a CD-R mainly depends on the proper
storing and
handling of the media.


MAGNETIC TAPE:

Projections that are now becoming available from a variety of
sources,
including the National Media Lab, which indicate that analog reel to
reel
tapes and players will be come obsolete with in the next ten years.
Coupled with the possibility of the loss of the material on the master
tapes, due to a variety of factors including the inexorable
degradation of
the magnetic information as well as the self destructive nature of
some
tape media, a migrational stratagem needs to be considered.  It
has been
highly recommended that this migration be made to a digital media
format.
There may be a good analogy to this potential problem.  That
circumstance
is the loss of images that were on nitrate film, it is a cautionary
reminder of what could effectively occur to magnetic tape.  Most of
the
magnetic tape manufactured today is stable but vast quantities of
the media
produced over the past 30 years have signs of being problematic.

Magnetic tape is basically ferrous oxide particles that are applied
onto a
backing with a binder to make it adhere.  There are four backing
types;
paper, acetate, polyester and PVC.  Each type has its own issues
with
regard to storage and playback.  Paper backed tapes become
acidic, acetate
formulations become brittle, and polyester tapes may become
sticky.  The
major concerns are those tapes that exhibit brittleness and
stickiness,
these are the products of natural tape aging, and can occur even in
properly stored tapes.

Other problems that occur in tapes are the various level settings in
which
can occur due to poorly set levels or mis-calibrated machines. This
can
lead  to distortion on playback as well as  print-through.  This
occurs
when the signal on one layer of tape is imposed on the adjacent
layer.  The
improper winding of a tape will result in warped tape as well as with
the
possibility of damage on playback.  Leader tape and tape splices
are common
artifacts found in many tapes.  Splicing tape, usually short pieces,
were
used when tapes were edited or possibly repaired.  These may dry
out which
permits the tape to separate during winding or play.  Some points
become
sticky and adhere to adjacent tape layers.  Both of which will
?clog? the
transport path, which then requires immediate maintenance.
Leader tape
typically was affixed to tapes, this also can become problematic
and
requires close inspection.  It is likely that on older tapes it needs to
be
replaced before it can be played.  Tapes can become warped from a


variety of factors including heat and improper storage, if this occurs
it
can be flattened out but requires special restoration and storage
time.
Acoustically this particular problem is less severe with speech than
with
music programs.  As if the problems encountered with magnetic
tape were not
complicated enough another challenge that requires special
handling and
restoration is  that of fungi.

Squealing or ?sticky state? tape syndrome occurs on polyester tape and is
part of the media?s aging process.  It is a result of the absorption of
water by the binder that holds the oxide coating onto the plastic backing.
The sticky material that comes will adhere to any point in the tape path
that the media touches eventually coating and then clogging them entirely.
The method for temporarily ?restoring? this type of tape, in order to play
it back with the sole objective of making a duplicate, is heating it.  By
heating the tape the water is baked out of the tape.  This must be done
with precisely controlled parameters over a few hours time, after which the
tape will play well enough.  The transfer of material is a limited window
of approximately four weeks after which it will revert to its ?sticky?
state.  One of the more recent innovations in tape restoration has been the
use of a hyperbolic chamber.  This permits the water vapor to be evaporated
at a lower temperature with less likelihood in damaging th


e tape.  Some of the tape names and numbers exhibiting this particular
problem include but are certainly not limited to: Ampex 406, 407, 456, 457.
3M 153, 206, 207, 208, 209, 217, 219, 226, 227, 806, 807, 808, 809, Classic
DP, Classic LP, Classic SP, Master and Master SX.

Another major problem is the brittle tape syndrome.  This is found on
acetate backed tapes.  The reel can easily be identified if held up to a
bright light source they will appear translucent.  As opposed to polyester
tapes, which look opaque.  The water content in the plasticizer evaporates
with time and good many of the tapes produced in the 1950?s & 60?s have now
become brittle.  In most cases these can be restored somewhat in six to ten
months to a playable condition. This is achieved most commonly by
containing them in a specialized container at varying humidity and
temperature ranges.  It is important to determine the type of tape since
these two disparate procedures will accelerate the deterioration of the
media if applied to the wrong tape inadvertently.

The Phillips standard audio compact cassette was first distributed in 1966.
It uses a 1/8? wide tape and was designed originally with a maximum of 90
minutes of tape time, 45 minutes on each side.  The 120 minute tape was
produced and uses a thinner tape formulation.  This particular tape is
much more prone to stretching, wrinkling and jamming.  Since the cassette
tape was a more popular format, in the consumer market, the archivist needs
to be aware of a number of idiosyncrasies associated with this particular
media.  Most end users were not aware their machines tape path and heads
had to be cleaned and demagnetized regularly.  As a result many tapes are
noisy and exhibit a loss in the higher frequency range.  Additionally weak
batteries in portable machines, all to often a common problem, caused the
tape to slow down in the record process resulting in a higher pitch when
played back at a standard speed.  Damaged and broken cassettes can easily
be repaired with little or no consequential damage to the tape


 inside this is  one of the few saving graces of the format.


CONCLUSIONS:

In general analog magnetic tape is a robust media, the associated problems
though make it anything other than archival.  There is no simple quick fix
to the problem.  It appears that the migration within the digital domain is
more transparent and technically easier to accomplish.  The major problem,
as we are now witnessing with analog domain, is being sure that the
playback device will be around when it comes time to migrate.  This aspect
needs to be addressed in the collection?s management planning.  It is not
only a technical matter but also a management strategy, one that requires
regular and planned intervention, as well as anticipating rather than
reacting to problems.  The process should take into account the need to
migrate to new media regularly.  One that uses the most appropriate
technology available within budgetary constraints, along with meeting the
archival quality criteria.  This planning should also take into account the
possibility of physical damage whether by fire, flooding or machine malf


unction.  No single format will last indefinitely, regardless of what any
accelerated test or manufacturer claims.  Additionally there is always the
unknown danger of spontaneous deterioration, as is evident in other media
and formats.  A continuous quality control, particularly of the
preservation copies, with the appropriate measurements of error rates or
drop-outs every few years would help ascertain the longevity of the
collection.  The typical preservation strategy suggests that there be two
master or preservation copies, each on a different media, and that
these be
stored in separate locations.  The question as to its feasibility or
whether it is economically viable needs to ascertained as well.
Proper
storage conditions and a thorough database of the content and
location of
all material, including the working copies is just as important.
Using
separate working copies for routine access, thus preserving, the
masters or
originals is essential.  Finally there should be a regular planned
assessment of th


e technologies being used as well as that of any new technologies
and the
impact upon the collection as a whole.


PRECAUTIONS & CONSIDERATIONS:

All audio media formats depend on some form of technology for
playback as
well as recording.  This simple fact increases the susceptibility to
mechanical or electrical failure, thereby rendering either or both the
media and the record playback mechanism unusable.  What is
often required
of an individual, working with audio media, is far more exacting than
can
be imagined by the uninitiated.  ?What ever can go wrong will go
wrong,? so
said Mr. Murphy, and he added ?and at the worst possible
moment.?

The necessity of having a high level of technical expertise, in
operating
and maintaining audio media equipment, is not a requirement for an
audio
archivist though a thorough understanding of the operation and use
of audio
equipment should be a requirement.  Archive technicians,
members of the
museum staff or anyone required to handle or use audio media and
the
related hardware should have some working knowledge as well.
There are
certain fundamental ?do?s and don?ts? that should be incorporated
as part
of an operating procedure.

1. After recording on any audio tape cassette, it is important to
break off
the ?record tab,? so that the recording cannot be accidentally or
intentionally overwritten.  Likewise, prior to re-recording any original
cassette, it should be ensured that the ?record tab? has been
removed from
the original cassette, so that the tape cannot be accidentally or
intentionally overwritten.

2. Any and all tapes, particularly original cassettes, should be
examined
before being placed in the tape deck.  It is important to determine if
there is any evidence of damage or other complication, which might
prohibit
a good copy from being made.  While turning the take-up reel with
a finger
(generally it would be the reel on the right side) while looking at the
face of the tape where it makes contact with the record/play head
see and
feel if there are any problems with the tapes easy motion.  If there
are
any difficulties then the cassette housing needs to be either
repaired or
replaced.  This can be readily accomplished by either unscrewing
or gently
breaking open the case and transferring tape to a new cassette
case or
freeing up the reels.

3. All tapes should be cleaned before they are played; a cleaning
machine
with a polyester tissue-based ribbon is optimal.  A standard policy
concerning tapes with signs of physical deterioration should be
established.  It might be best to contact a facility with audio
conservation experience before any effort of restoration is
attempted.

4. The current standard for audio preservation masters is 1/4?
reel-to-reel, non- chrome (Type II gFeO2), on a10? diameter reel.
There
are a number of reasons for this: the tape is thicker and more
durable;
lessens or prevents ?print through;? and is not subject to the
oxidation
problems of chrome-doped tapes generally have.  After recording
the tape
should be wound with the tails out, (the tape has to be rewound to
play
back).

5. The audio tape playback machine should be cleaned every time
an original
cassette or reel-to-reel tape is played on it.  This means that the
machine
should be cleaned twice when a two-sided tape is played on it.
Correspondingly, the cassette or reel-to-reel tape recorder, which is
making the copies, should be cleaned frequently.  Routine
calibration and
mechanical maintenance should be carried out on all the machines
used.

6. The CD and tape copies made should be listened to in order to
insure
that there are no problems in the new recording.  If any original tape
exhibits severe problems, which inhibit intelligibility, they should be
set
aside and marked for future audio filtering.  Signal processing can
be
readily be implemented to decrease the noise and enhance the
speech range.

7. The archive life expectancy of a CD-R mainly depends on the
proper
storing and handling of the media.  CD-R?s should be stored at low,
constant temperature and humidity.  They should be kept out of
direct
sunlight and should be kept in their protective ?jewel? cases to
safeguard
them from damage.  Scratches and contaminants on the playing
surface can
result in their being unreadable by a CD player.  CD-R?s should
only be
written on the label or top side, with a soft tipped pen that contains
no
solvents least it corrodes the surface of the disc.  Felt tip pens are
fine
though ball point pens could very easily damage the disc.


END NOTES:

                                   CD-R test
A Reader *Really* Torture-Tests His Backups

LangaList reader Jean-Claude Racine is in a somewhat unique
circumstance,
but one that many of us might envy: He cruises the world in his
yacht and
downloads his LangaList issues via direct satellite Internet link!

Being far from help and any support services, backups are
especially
important for Jean-Claude, and as such, he put his to an extreme
test that
I bet no other reader has done.  I sure haven?t! <g>

Off Pulau Tenggol, Malaysia, October 20, 2000

Dear Fred: Thanks a lot for great Newsletter, which I highly
appreciate
while sailing around the world.  In your October 16 edition [ see
http://www.winmag.com/columns/explorer/2000/20.htm ), you say
that
?CD-based backups are best-of-breed?.  Well, let me tell you that I
am
backing up my data on board every day on a CD-RW.  This CD is
placed near
the grab bag in the event we should one day abandon ship.
Knowing that
this CD would inevitably get wet and salty in a survival situation, I
tested it by keeping it during two weeks in a bucket of saltwater,
exposed
to sun.  After this, I just rinsed the CD with clear water and a little
bit
of vinegar (to remove the salt), dried it and put it in my laptop.
Would
you believe it? All the data were perfectly readable and usable.
You are
right when you say that CD-based backups are best-of-breed!

Jean-Claude Racine (Switzerland) Yacht Na-Maka-o-Kaha?i

Talk about a torture-test! Don?t try that with your hard-drive, Zip or
tape
based backups!

That CD ruggedness, plus the fact that each blank CD costs only
half a buck
and holds 640MB, makes CDs great for long-term, inexpensive,
and extremely
long-lived archiving.  Even for those of us who *don?t* live on
yachts. <g>



BIBLIOGRAPHY & RESOURCES:

Koichi Sadashge
Data Storage Technology Assessment 2000
National Media Laboratory, 2000

Council on Library Resources http://www-clr.stanford.edu/clr/

Andy McFadden
CD-Recordable FAQ
Online internet article, 2000

Dana J. Parker
The Rest of the Rest of the Story: Shedding Some Coherent Light
on CD-R
Online internet article, 2000 The CD-Info Company, Inc.


Jim Lindner
Magnetic Tape Deterioration: Tidal Wave at Our Shores
Digitization Reconsidered
Confessions of a Videotape Restorer
Videotape Restoration - Where Do I Start?
The Proper Care and Feeding of Videotape
The Last 40 Years
Online internet article, 2000 VidiPax

more....

************************************************

Thanks again for all the replies.  They helped more than you can
know!

Sincerely,


Tawnya Mosier
Film and AV Archivist
Special Collections
J. Willard Marriott Library
University of Utah
Salt Lake City, Utah
(801) 585-3073
(801) 585-3976 (FAX)

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