obsolete media

Mouldy DATs

We have previously written on this blog about the problems that can occur when transferring Digital Audio Tapes (DATs).

According to preliminary findings from the British Library’s important survey of the UK’s sound collections, there are 3353 DAT tapes in the UK’s archives.

While this is by no means a final figure (and does not include the holdings of record companies and DATheads), it does suggest there is a significant amount of audio recorded on this obsolete format which, under certain conditions, is subject to catastrophic signal loss.

The conditions we are referring to is that old foe of magnetic tape: mould.

In contrast with existing research about threats to DAT, which emphasise how the format is threatened by ‘known playback problems that are typically related to mechanical alignment’, the biggest challenges we consistently face with DATs is connected to mould.

It is certainly acknowledged that ‘environmental conditions, especially heat, dust, and humidity, may also affect cassettes.’

Nevertheless, the specific ways mould growth compromise the very possibility of successfully playing back a DAT tape have not yet been fully explored. This in turn shapes the kinds of preservation advice offered about the format.

What follows is an attempt to outline the problem of mould growth on DATs which, even in minimal form, can pretty much guarantee the loss of several seconds of recording.

DAT Tape Size Tape width issues

The first problem with DATs is that they are 4mm wide, and very thin in comparison to other forms of magnetic tape.

The size of the tape is compounded by the helical method used in the format, which records the signal as a diagonal stripe across the tape. Because tracks are written onto the tape at an angle, if the tape splits it is not a neat split that can be easily spliced together.

The only way to deal with splits is to wind the tape back on to the tape transport or use leder tape to stick the tape back together at the breaking point.

Either way, you are guaranteed to lose a section of the tape because the helical scan has imprinted the recorded signal at a sharp, diagonal angle. If a DAT tape splits, in other words, it cuts through the diagonal signal, and because it is digital rather than analogue audio, this results in irreversible signal loss.

And why does the tape split? Because of the mould!

If you play back a DAT displaying signs of dormant mould-growth it is pretty much guaranteed to split in a horrible way. The tape therefore needs to be disassembled and wound by hand. This means you can spend a lot of time restoring DATs to a playable condition.

Rewinding by hand is however not 100% full proof, and this really highlights the challenges of working with mouldy DAT tape.

Often mould on DATs is visible on the edge of the tape pack because the tape has been so tightly wound it doesn’t spread to the full tape surface.

In most cases with magnetic tape, mould on the edge is good news because it means it has not spread and infected the whole of the tape. Not so with DAT.

Even with tiny bits of mould on the edge of the tape there is enough to stick it to the next bit of tape as it is rewound.

When greater tension is applied in an attempt to release the mould, due to stickiness, the tape rips.

A possible and plausible explanation for DAT tape ripping is that due to the width and thinness of the tape the mould is structurally stronger than the tape itself, making it easier for the mould growth to stick together.

When tape is thicker, for example with a 1/4 ” open reel tape, it is easier to brush off the dormant mould which is why we don’t see the ripping problem with all kinds of tape.

Our experience confirms that brushing off dormant mould is not always possible with DATs which, despite best efforts, can literally peel apart because of sticky mould.

What, then, is to be done to ensure that the 3353 (and counting) DAT tapes in existence remain in a playable condition?

One tangible form of action is to check that your DATs are stored at the appropriate temperature (40–54°F [4.5–12°C]) so that no mould growth develops on the tape pack.

The other thing to do is simple: get your DAT recordings reformatted as soon as possible.

While we want to highlight the often overlooked issue of mould growth on DATs, the problems with machine obsolescence, a lack of tape head hours and mechanical alignment problems remain very real threats to successful transfer of this format.

Our aim at the Greatbear is to continue our research in the area of DAT mould growth and publish it as we learn more.

As ever, we’d love to hear about your experiences of transferring mouldy DATs, so please leave a comment below if you have a story to share.

 

Posted by debra in Audio Tape, 0 comments

1″ type A Video Tape – The Old Grey Whistle Test

Sometimes genuine rarities turn up at the Great Bear studio. Our recent acquisition of four reels of ‘missing, believed wiped’ test recordings of cult BBC TV show The Old Grey Whistle Test is one such example. Old Grey Whistle Test Ampex reel

It is not only the content of these recordings that are interesting, but their form too, because they were made on 1” type A videotape.

The Ampex Corporation introduced 1” Society of Motion Picture and Television Engineers (SMPTE) type A videotape in 1965.

The 1″ type A was ‘one of the first standardized reel-to-reel magnetic tape formats in the 1 inch (25 mm) width.’ In the US it had greatest success as an institutional and industrial format. It was not widely adopted in the broadcast world because it did not meet Federal Communications Commission (FCC) specifications for broadcast videotape formats—it was capable of 350 lines, while the NTSC standard was 525, PAL and SECAM were 625 (for more information on television standards visit this page, also note the upcoming conference ‘Standards, Disruptions and Values in Digital Culture and Communication‘ taking place November 2015).

According the VT Old Boys website, created by ex-BBC engineers in order to document the history of videotape used at the organisation, 2″ Quadruplex tape remained very much the norm for production until the end of the 1970s.

Yet the very existence of the Old Grey Whistle Test tapes suggests type A videotape was being used in some capacity in the broadcast world. Perhaps ADAPT, a project researching British television production technology from 1960-present, could help us solve this mystery?

Old Grey Whistle Test Reel From type A, to type B….

As these things go, type A was followed by type B, with this model developed by the German company Bosch. Introduced in 1976, type B was widely adopted in continental Europe, but not in UK and USA which gravitated toward the type C model, introduced by SONY/ Ampex, also in 1976. Type C then became the professional broadcast standard and was still being used well into the 1990s. It was able to record high quality composite video, and therefore had an advantage over component videos such as Betacam and MII that were ‘notoriously fussy and trouble-prone.‘ Type C also had fancy functions like still, shuttle, variable-speed playback and slow motion.

From a preservation assessment point of view, ‘one-inch open reel is especially susceptible to risks associated with age, hardware, and equipment obsolescence. It is also prone to risks common to other types of magnetic media, such as mould, binder deterioration, physical damage, and signal drop-outs.’

1" Type A Machine

The Preservation Self-Assessment Programme advise that ‘this format is especially vulnerable, and, based on content assessment, it should be a priority for reformatting.’

AMPEX made over 30 SMPTE type A models, the majority of which are listed here. Yet the number of working machines we have access to today is few and far between.

In years to come it will be common for people to say ‘it takes four 1” type A tape recorders to make a working one’, but remember where you heard the truism first.

Harvesting several of these hulking, table-top machines for spares and working parts is exactly how we are finding a way to transfer these rare tapes—further evidence that we need to take the threat of equipment obsolescence very seriously.

Posted by debra in Video Tape, 1 comment

Save our Sounds – 2030 and the threat of audiovisual extinction

At the beginning of 2015, the British Library launched the landmark Save Our Sounds project.

The press release explained:

‘The nation’s sound collections are under threat, both from physical degradation and as the means of playing them disappear from production. Archival consensus internationally is that we have approximately 15 years in which to save our sound collections by digitising them before they become unreadable and are effectively lost.’

dvw-a510-digital-betacam-loading-gear Yes you have read that correctly dear reader: by 2030 it is likely that we simply will not be able to play many, if not all of the tape we currently support at Great Bear. A combination of machine obsolescence, tape deterioration and, crucially, the widespread loss of skills necessary to repair, service and maintain playback machines are responsible for this astounding situation. They will make it ‘costly, difficult and, in many cases, impossible’ to preserve our recorded audio heritage beyond the proposed cut-off date.

While such news might (understandably) usher in a culture of utter panic, and, let’s face it, you’d have to have a strong disposition if you were charged with managing the Save Our Sounds project, the British Library are responding with stoic pragmatism. They are currently undertaking a national audit to map the conditions of sound archives which your organisation can contribute to.

Yet whatever way you look at it, there is need to take action to migrate any collections currently stored on obsolete media, particular if you are part of a small organisation with limited resources. The reality is it will become more expensive to transfer material as we move closer to 2030. The British Library project relates particularly to audio heritage, but the same principles apply to audiovisual collections too.

Yes that rumbling you can hear is the sound of archivists the world over engaged in flurry of selection and appraisal activities….

Extinction

One of the most interesting things about discussions of obsolete media is that the question of operability is often framed as a matter of life or death.

Formats are graded according to their ‘endangered statuses’ in more or less explicit terms, as demonstrated on this Video Preservation website which offers the following ‘obsolescence ratings’:

‘Extinct: Only one or two playback machines may exist at specialist laboratories. The tape itself is more than 20 years old.

Critically endangered: There is a small population of ageing playback machinery, with no or little engineering or manufacturing support. Anecdotal evidence indicates that there are fewer working machine-hours than total population of tapes. Tapes may range in age from 40 years to 10 years.

Endangered: The machine population may be robust, but the manufacture of the machinery has stopped. Manufacturing support for the machines and the tapes becomes unavailable. The tapes are often less expensive, and more vulnerable to deterioration.

Threatened: The playback machines are available; however, either the tape format itself is unstable or has less integrity than other available formats, or it is known that a more popular or updated format will be replacing this one in a short period of time.

Vulnerable: This is a current but highly proprietary format.

Lower risk: This format will be in use over the next five years (1998-2002).’

The ratings on the video preservation website were made over ten years ago. A more comprehensive and regularly updated resource to consult is the Preservation Self-Assessment Program (PSAP), ‘a free online tool that helps collection managers prioritize efforts to improve conditions of collections. Through guided evaluation of materials, storage/exhibit environments, and institutional policies, the PSAP produces reports on the factors that impact the health of cultural heritage materials, and defines the points from which to begin care.’ As well as audiovisual media, the resource covers photo and image material, paper and book preservation. It also has advice about disaster planning, metadata, access and a comprehensive bibliography.

The good news is that fantastic resources do exist to help archivists make informed decisions about reformatting collections.

dcc-backview

A Digital Compact Cassette

The bad news, of course, is that the problem faced by audiovisual archivists is a time-limited one, exacerbated no doubt by the fact that digital preservation practices on the ‘output end’ are far from stable. Finding machines to playback your Digital Compact Cassette collection, in other words, will only be a small part of the preservation puzzle. A life of file migrations in yet to be designed wrappers and content-management systems awaits all kinds of reformatted audiovisual media in their life-to-come as a digital archival object.

Depending on the ‘content value’ of any collection stored on obsolete media, vexed decisions will need to be made about what to keep and what to throw away at this clinical moment in the history of recorded sound.

Sounding the fifteen-year warning

At such a juncture, when the fifteen year warning has been sounded, perhaps we can pause for a second to reflect on the potential extinction of large swathes of audio visual memory.

If we accept that any kind of recording both contains memory (of a particular historical event, or performance) and helps us to remember as an aide-mémoire, what are the consequences when memory storage devices which are, according to UNESCO, ‘the primary records of the 20th and 21st centuries’, can no longer be played back?

These questions are of course profound, and emerge in response to what are consequential historical circumstances. They are questions that we will continue to ponder on the blog as we reflect on our own work transferring obsolete media, and maintaining the machines that play them back. There are no easy answers!

As the 2030 deadline looms, our audiovisual context is a sobering retort to critics who framed the widespread availability of digitisation technologies in the first decade of the 21st century as indicative of cultural malaise—evidence of a culture infatuated with its ‘past’, rather than concerned with inventing the ‘future’.

Perhaps we will come to understand the 00s as a point of audiovisual transition, when mechanical operators still functioned and tape was still in fairly good shape. When it was an easy, almost throw away decision to make a digital copy, rather than an immense preservation conundrum. So where once there was a glut of archival data—and the potential to produce it—is now the threat of abrupt and irreversible dropout.

Play those tapes back while you can!

Posted by debra in Audio Tape, Video Tape, 0 comments

Obsolete technologies and contemporary sound art

At the recent Supernormal festival held at Braziers Park, Oxfordshire, a number of artists were using analogue technologies to explore concepts that dovetail nicely with the work we do at Great Bear collecting, servicing and repairing obsolete tape machines.

Hacker Farm, for example, keep ‘obsolete tech and discarded, post-consumerist debris’ alive using ‘salvaged and the hand-soldered’ DIY electronics. Their performance was a kind-of technological haunting, the sound made when older machines are turned on and re-purposed in different eras. Eerie, decayed, pointless and mournful, the conceptual impetus behind Hacker Farm raises many questions that emerge from the rather simple desire to keep old technologies working. Such actions soon become strange and aesthetically challenging in the contemporary technological context, which actively reproduces obsolescence in the endless search for the new, fostering continuous wastefulness at the centre of industrial production.

Music by the Metre

Another performance at the festival which engaged with analogue technologies was Graham Dunning’s Music by the Metre. The piece pays homage to Situationist Pinot-Gallizio‘s method of ‘Industrial Painting’ (1957-1959), in which the Italian artist created a 145 metre hand and spray painted canvas that was subsequently cut up and sold by the metre. The action, which attempted to destroy the perception of the sacrilegious art-object and transform it into something which could be mass-quantified and sold, aimed to challenge ‘the mental disease of banalisation’ inherent to what Guy Debord termed ‘the society of the spectacle.’

In Dunning’s contemporary piece he used spools of open reel tape to record a series of automated machines comprised of looping record players, synth drone, live environmental sound and tape loops. This tape is then cut by the artist in metre long segments, placed in see-through plastic bags and ‘sold’ on his temporary market stall used to record and present the work.

Dunning’s work exists in interesting tension with the ideas of Pinot-Gallizio, largely because of the different technological and aesthetic contexts the artists are responding to.

Pinot-Gallizio’s industrial painting aimed to challenge the role of art within a consumer society by accelerating its commodity status (mass-produced, uniform, quantified, art as redundant, art as part of the wall paper). Within Dunning’s piece, such a process of acceleration is not so readily available, particularly given the deep obsolescence of consumer-grade open reel tape in 2014, and, furthermore, its looming archival obsolescence (often cited at ’10-20 years‘ by archivists).

Within the contemporary context, open reel analogue tapes have become ornate and aestheticised in themselves because they have lost their function as an everyday, recordable mass blank media. When media lose their operating context they are transformed into objects of fascination and desire, as Claire Bishop pithily states in her Art Forum essay, ‘The Digital Divide’: ‘Today, no exhibition is complete without some form of bulky, obsolete technology—the gently clucking carousel of the slide-projector, or the whirring of an 8mm or 16mm film reel […] the sumptuous texture of indexical media is unquestionably seductive, but its desirability also arises from the impression that it is scarce, rare and precious.’

In reality, the impression of open reel to reel analogue tape’s rarity is however well justified, as manufacturers and distributors of magnetic tape are increasingly hard to find. Might there be something more complex and contradictory be going on in Dunning’s homage to Pinot-Gallizio? Could we understand it as a neat inversion of the mass-metred-object, doubly cut adrift from its historical (1950s-1970s) and technological operating context (the open reel tape recorder), the bag of tape is decelerated, existing as nothing other than art object. Stuffed messily in a plastic bag and displayed ready to be sold (if only by donation), the tape is both ugly and useless given its original and intended use. It is here Dunning’s and Pinot-Gallizio’s work converge, situated at different historical and temporal poles from which critique of the consumer society can be mounted: accelerated plenitude and decelerated exhaustion.

onexmetres

Analogue attachments

As a company that works with obsolete magnetic tape-based media, Great Bear has a vested interest in ensuring tapes and playback machines remain operational. Although our studio, with its stacks of long-forgotten machines, may look like a curious art installation to some, the tapes we migrate to digital files are not quite art objects…yet. Like Hacker Farm, we help to keep old media alive through careful processes of maintenance and repair.

From looking at how contemporary sound artists are engaging with analogue technologies, it is clear that the medium remains very much part of the message, as Marshall McLuhan would say, and that meaning becomes amplified, contorted or transformed depending on historical context, and media norms present within it.

Posted by debra in Audio Tape, 0 comments

D1, D2 & D3 – histories of digital video tape

D1 tape

The images in this article are of the first digital video tape formats, the D1, D2 and D3. The tendency to continually downsize audiovisual technology is clearly apparent: the gargantuan shell of the D1 gradually shrinks to the D3, which resembles the size of a domestic VHS tape.

Behind every tape (and every tape format) lie interesting stories, and the technological wizardry and international diplomacy that helped shape the roots of our digital audio visual world are worth looking into.

In 1976, when the green shoots of digital audio technology were emerging at industry level, the question of whether Video Tape Recorders (VTRs) could be digitised began to be explored in earnest by R & D departments based at SONY, Ampex and Bosch G.m.b.H. There was considerable scepticism among researchers about whether digital video tape technology could be developed at all because of the wide frequency required to transmit a digital image.

In 1977 however, as reported on the SONY websiteYoshitaka Hashimoto and team began to intensely research digital VTRs and ‘in just a year and a half, a digital image was played back on a VTR.’

Several years of product development followed, shaped, in part, by competing regional preferences. As Jim Slater argues in Modern Television Systems (1991): ‘much of the initial work towards digital standardisation was concerned with trying to find ways of coping with the three very different colour subcarrier frequencies used in NTSC, SECAM and PAL systems, and a lot of time and effort was spent on this’ (114).

Establishing a standard sampling frequency did of course have real financial consequences, it could not be randomly plucked out the air: the higher the sampling frequency, the greater overall bit rate; the greater overall bit rate, the more need for storage space in digital equipment. In 1982, after several years of negotiations, a 13.5 MHz sampling frequency was agreed. European, North American, ‘Japanese, the Russians, and various other broadcasting organisations supported the proposals, and the various parameters were adopted as a world standard, Recommendation 601 [a.k.a. 4:2:2 DTV] standard of the CCIR [Consultative Committee for International Radio, now International Telecommunication Union]’ (Slater, 116).

The 4:4:2 DTV was an international standard that would form the basis of the (almost) exclusively digital media environment we live in today. It was ‘developed in a remarkably short time, considering its pioneering scope, as the worldwide television community recognised the urgent need for a solid basis for the development of an all-digital television production system’, write Stanley Baron and David Wood.

Once agreed upon, product development could proceed. The first digital video tape, the D1, was introduced on the market in 1986. It was an uncompressed component video which used enormous bandwidth for its time: 173 Mbit/sec (bit rate), with maximum recording time of 94 minutes.  D-2 and D-3 Tapes

As Slater writes

‘unfortunately these machines are very complex, difficult to manufacture, and therefore very expensive […] they also suffer from the disadvantage that being component machines, requiring luminance and colour-difference signals at input and output, they are difficult to install in a standard studio which has been built to deal with composite PAL signals. Indeed, to make full use of the D1 format the whole studio distribution system must be replaced, at considerable expense’ (125).

Being forced to effectively re-wire whole studios, and the considerable risk involved in doing this because of continual technological change, strikes a chord with the challenges UK broadcast companies face as they finally become ‘tapeless’ in October 2014 as part of the Digital Production Partnership’s AS-11 policy.

Sequels and product development

As the story so often goes, D1 would soon be followed by D2. Those that did make the transition to D1 were probably kicking themselves, and you can only speculate the amount of back injuries sustained getting the machines in the studio (from experience we can tell you they are huge and very heavy!)

It was fairly inevitable a sequel would be developed because even as the D-1 provided uncompromising image quality, it was most certainly an unwieldy format, apparent from its gigantic size and component wiring. In response a composite digital video – the D2 – was developed by Ampex and introduced in 1988.

In this 1988 promotional video, you can see the D-2 in action. Amazingly for our eyes and ears today the D2 is presented as the ideal archival format. Amazing for its physical size (hardly inconspicuous on the storage shelf!) but also because it used composite video signal technology. Composite signals combine on one wire all the component parts which make up a video signal: chrominance (colour, or Red Green, Blue – RGB) and luminance (the brightness or black and white information, including grayscale).

While the composite video signal used lower bandwidth and was more compatible with existing analogue systems used in the broadcast industry of the time, its value as an archival format is questionable. A comparable process for the storage we use today would be to add compression to a file in order to save file space and create access copies. While this is useful in the short term it does risk compromising file authenticity and quality in the long term. The Ampex video is fun to watch however, and you get a real sense of how big the tapes were and the practical impact this would have had on the amount of time it took to produce TV programmes.

Enter the D3

Following the D2 is the D3, which is the final video tape covered in this article (although there were of course the D5 and D9.)

The D3 was introduced by Panasonic in 1991 in order to compete with Ampex’s D2. It has the same sampling rate as the D2 with the main difference being the smaller shell size.

The D3’s biggest claim to fame was that it was the archival digital video tape of choice for the BBC, who migrated their analogue video tape collections to the format in the early 1990s. One can only speculate that the decision to take the archival plunge with the D3 was a calculated risk: it appeared to be a stable-ish technology (it wasn’t a first generation technology and the difference between D2 and D3 is negligible).

The extent of the D3 archive is documented in a white paper published in 2008, D3 Preservation File Format, written by Philip de Nier and Phil Tudor: ‘the BBC Archive has around 315,000 D3 tapes in the archive, which hold around 362,000 programme items. The D3 tape format has become obsolete and in 2007 the D3 Preservation Project was started with the goal to transfer the material from the D3 tapes onto file-based storage.’

Tom Heritage, reporting on the development of the D3 preservation project in 2013/2014, reveals that ‘so far, around 100,000 D3 and 125,000 DigiBeta videotapes have been ingested representing about 15 Petabytes of content (single copy).’

It has then taken six years to migrate less than a third of the BBC’s D3 archive. Given that D3 machines are now obsolete, it is more than questionable whether there are enough D3 head hours left in existence to read all the information back clearly and to an archive standard. The archival headache is compounded by the fact that ‘with a large proportion of the content held on LTO3 data tape [first introduced 2004, now on LTO-6], action will soon be required to migrate this to a new storage technology before these tapes become difficult to read.’ With the much publicised collapse of the BBC’s (DMI) digital media initiative in 2013, you’d have to very strong disposition to work in the BBC’s audio visual archive department.

The roots of the audio visual digital world

The development of digital video tape, and the international standards which accompanied its evolution, is an interesting place to start understanding our current media environment. They are also a great place to begin examining the problems of digital archiving, particularly when file migration has become embedded within organisational data management policy, and data collections are growing exponentially.

While the D1 may look like an alien-techno species from a distant land compared with the modest, immaterial file lists neatly stored on hard drives that we are accustomed to, they are related through the 4:2:2 sample rate which revolutionised high-end digital video production and continues to shape our mediated perceptions.

Posted by debra in Video Tape, 0 comments

The difference ten years makes: changes in magnetic tape recording and storage media

Data Storage Catalogue_front_2004 Generational change for digital technologies are rapid and disruptive.  ‘In the digital context the next generation may only be five to ten years away!’ Tom Gollins from the National Archives reminds us, and this seems like a fairly conservative estimate.

It can feel like the rate of change is continually accelerating, with new products appearing all the time. It is claimed, for example, that the phenomena of ‘wearable tech chic’ is now upon us, with the announcement this week that Google’s glass is available to buy for £1,000.

The impact of digital technologies have been felt throughout society, and this issue will be explored in a large immersive exhibition of art, design, film, music and videogames held at the Barbian July-Sept 2014. It is boldly and emphatically titled: Digital Revolution.

To bring such technological transformations back into focus with our work at Great Bear, consider this 2004 brochure that recently re-surfaced in our Studio. As an example of the rapid rate of technological change, you need look no further.

A mere ten years ago, you could choose between several brands of audio mini disc, ADAT, DAT, DTRS, Betacam SP, Digital Betacam, super VHS, VHS-C, 8mm and mini DV.

Data Storage Catalogue_back_2004 Storage media such as Zip disks, Jaz CartExabytes and hard drives that could store between 36-500Gb of data were also available to purchase.

RMGI are currently the only manufacturer of professional open reel audio tape. In the 2004 catalogue, different brands of open reel analogue tape are listed at a third of 2014 retail prices, taking into account rates of inflation.

While some of the products included in the catalogue, namely CDs, DVDs and open reel tape, have maintained a degree of market resiliency due to practicality, utility or novelty, many have been swept aside in the march of technological progress that is both endemic and epidemic in the 21st century.

 

 

Posted by debra in Audio Tape, Video Tape, 1 comment

Digitising Stereo Master Hi-Fi VHS Audio Recordings

The history of amateur recording is peppered with examples of people who stretched technologies to their creative limit. Whether this comes in the form of hours spent trying things out and learning through doing, endlessly bouncing tracks in order to turn an 8-track recording into a 24-track epic or making high quality audio masters on video tape, people have found ways to adapt and experiment using the tools available to them.

Hollow Hand Demos

One of the lesser known histories of amateur home recordings is making high quality stereo mixdowns and master recordings from multi-track audio tape onto consumer-level Hi-Fi VCRs.

We are currently migrating a stereo master VHS Hi-Fi recording of London-based indie band Hollow Hand. Hollow Hand later adopted the name Slanted and were active in London between 1992-1995. The tapes were sent in by Mark Venn, the bass player with Slanted and engineer for these early recordings that were recorded in 1992 in the basement of a Clapham squat. Along with the Hi-Fi VHS masters, we have also been sent eight reels of AMPEX ¼ tapes of Slanted that are being transferred for archival purposes. Mark intends to remix the eight track recordings digitally but as of yet has no plans for a re-release.

When Mark sent us the tapes to be digitised he thought they had been encoded with a SONY PCM, a mixed digital/ analogue recording method we have covered in a previous blog post. The tapes had, however, been recorded directly from the FOSTEX eight track recorder to the stereo Hi-Fi function on a VHS video tape machine. For Mark at the time this was the best way to get a high quality studio master because other analogue and digital tape options, such as Studer open reel to reel and DAT machines, were financially off-limits to him. It is worth mentioning that Hi-Fi audio technologies were introduced in the VHS model by JVC around 1984, so using this method to record stereo masters would have been fairly rare, even among people who did a lot of home recording. It was certainly a bit of a novelty in the Great Bear Studio – they are the first tapes we have ever received that have been recorded in this way – and take it for granted that we see a lot of tape.

Using the Hi-Fi function on VHS tape machines was probably as good as it got in terms of audio fidelity for those working in an exclusively analogue context. It produced a master recording comparable in quality to a CD, particularly if the machine had manual audio recording level control. This is because, as we wrote about in relation to PCM/ Betamax, video tape could accommodate greater bandwidth that audio tape (particularly audio cassette), therefore leading to better quality recordings.

One of our replacement upper head drums

One of our replacement upper head drums

VHS Hi-Fi audio is achieved using audio frequency-modulation (AFM) and relied on a form of magnetic recording called ‘depth multiplexing‘. This is when

‘the modulated audio carrier pair was placed in the hitherto-unused frequency range between the luminance and the colour carrier (below 1.6 MHz), and recorded first. Subsequently, the video head erases and re-records the video signal (combined luminance and colour signal) over the same tape surface, but the video signal’s higher centre frequency results in a shallower magnetization of the tape, allowing both the video and residual AFM audio signal to coexist on tape.’

Challenges for migrating Hi-Fi VHS Audio

Although the recordings of Hollow Hand are in good working condition, analogue masters to VHS Hi-Fi audio do face particular challenges in the migration process.

Playing back the tapes in principle is easy if both tape and machine are in optimum condition, but if either are damaged the original recordings can be hard to reproduce.

A particular problem for Hi-Fi audio emerges when the tape heads wear and it becomes harder to track the hi-fi audio recording because the radio frequency signal (RF) can’t be read consistently off the tape. Hi-Fi recordings are harder to track because of depth multiplexing, namely the position of the recorded audio relative to the video signal. Even though there is no video signal as such in the playback of Hi-Fi audio, the video signal is still there, layered on top of the audio signal, essentially making it harder to access. Of course when tape heads/ drums wear down they can always be replaced, but acquiring spare parts will become increasingly difficult in years to come, making Hi-Fi audio recordings on VHS particularly threatened.

In order to migrate tape-based media to digital files in the most effective way possible, it is important to use appropriate machines for the transfer. The Panasonic AG-7650 we used to transfer the Hollow Hand tapes afforded us great flexibility because it is possible to select which audio tracks are played back at any given time which meant we could isolate the Hi-Fi audio track. The Panasonic AG-7650 also has tracking meters which makes it easy to assess and adjust the tracking of the tape and tape head where necessary.

As ever, the world of digitisation continues to generate anomalies, surprises and good stories. Who knows how many other video/ audio hybrid tapes are out there! If you do possess an archive collection of such tapes we advise you to take action to ensure they are migrated because of the unique problems they pose as a storage medium.

Posted by debra in Audio Tape, Video Tape, 0 comments

Digital Optical Technology System – ‘A non-magnetic, 100 year, green solution for data storage.’

‘A non-magnetic, 100 year, green solution for data storage.’

This is the stuff of digital information managers’ dreams. No more worrying about active data management, file obsolescence or that escalating energy bill.

Imagine how simple life would be if there was a way to store digital information that could last, without intervention, for nearly 100 years. Those precious digital archives could be stored in a warehouse that was not climate controlled, because the storage medium was resilient enough to withstand irregular temperatures.

Imagine after 100 years an archivist enters that very same warehouse to retrieve information requested by a researcher. The archivist pulls a box off the shelf and places it on the table. In their bag they have a powerful magnifying glass which they use to read the information. Having ascertained they have the correct item, they walk out the warehouse, taking the box with them. Later that day, instructions provided as part of the product licensing over 100 years ago are used to construct a reader that will retrieve the data. The information is recovered and, having assessed the condition of the storage medium which seems in pretty good nick, the digital optical technology storage is taken back to the warehouse where it sits for another 10 years, until it is subject to its life-cycle review. Group_47_DOTS

Does this all sound too good to be true? For anyone exposed to the constantly changing world of digital preservation, the answer would almost definitely be yes. We have already covered on this blog numerous issues that the contemporary digital information manager may face. The lack of standardisation in technical practices and the bewildering array of theories about how to manage digital data mean there is currently no ‘one size fits all’ solution to tame the archive of born-digital and digitised content, which is estimated to swell to 3,000 Exabytes (thousands of petabytes) by 2020*. We have also covered the growing concerns about the ecological impact of digital technologies, such as e-waste and energy over-consumption. With this in mind, the news that a current technology exists that can by-pass many of these problems will seem like manna from heaven. What can this technology be and why have you never heard about it?

The technology in question is called DOTS, which stands for Digital Optical Technology System. The technology is owned and being developed by Group 47, who ‘formed in 2008 in order to secure the patents, designs, and manufacturing processes for DOTS, a proven 100-year archival technology developed by the Eastman Kodak Company.’ DOTS is refreshingly different from every other data storage solution on the market because it ‘eliminates media and energy waste from forced migration, costly power requirements, and rigid environmental control demands’. What’s more, DOTS are ‘designed to be “plug & play compatible” with the existing Linear Tape Open (LTO) tape-based archiving systems & workflow’.

In comparison with other digital information management systems that can employ complex software, the data imaged by DOTS does not use sophisticated technology. John Lafferty writes that at ‘the heart of DOTS technology is an extremely stable storage medium – metal alloy sputtered onto mylar tape – that undergoes a change in reflectivity when hit by a laser. The change is irreversible and doesn’t alter over time, making it a very simple yet reliable technology.’

DOTS can survive the benign neglect all data experiences over time, but can also withstand pretty extreme neglect. During research and development, for example, DOTS was exposed to a series of accelerated environmental age testing that concluded ‘there was no discernible damage to the media after the equivalent of 95.7 years.’ But the testing did not stop there. Since acquiring patents for the technology Group 47,

‘has subjected samples of DOTS media to over 72 hours of immersion each in water, benzine, isopropyl alcohol, and Clorox (™) Toilet Bowl Cleaner. In each case, there was no detectable damage to the DOTS media. However, when subjected to the citric acid of Sprite carbonated beverage, the metal had visibly deteriorated within six hours.’

Robust indeed! DOTS is also non-magnetic, chemically inert, immune from electromagnetic fields and can be stored in normal office environments or extremes ranging from -9º – 65º C. It ticks all the boxes really.

DOTS vs the (digital preservation) world

The only discernible benefit of the ‘open all hours’, random access digital information culture over a storage solution such as DOTS is accessibility. While it certainly is amazing how quick and easy it is to retrieve valuable data at the click of a button, it perhaps should not be the priority when we are planning how to best take care of the information we create, and are custodians of. The key words here are valuable data. Emerging norms in digital preservation, which emphasise the need to always be responsive to technological change, takes gambles with the very digital information it seeks to preserve because there is always a risk that migration will compromise the integrity of data.

The constant management of digital data is also costly, disruptive and time-consuming. In the realm of cultural heritage, where organisations are inevitably under resourced, making sure your digital archives are working and accessible can sap energy and morale. These issues of course affect commercial organisations too. The truth is the world is facing an information epidemic, and surely we would all rest easier if we knew our archives were safe and secure. Indeed, it seems counter-intuitive that amid the endless flashy devices and research expertise in the world today, we are yet to establish sustainable archival solutions for digital data.

256px-Dictionary_through_lens (2)

Of course, using a technology like DOTS need not mean we abandon the culture of access enabled by file-based digital technologies. It may however mean that the digital collections available on instant recall are more carefully curated. Ultimately we have to ask if privileging the instant access of information is preferable to long-term considerations that will safeguard cultural heritage and our planetary resources.

If such a consideration errs on the side of moderation and care, technology’s role in shaping that hazy zone of expectancy known as ‘the future’ needs to shift from the ‘bigger, faster, quicker, newer’ model, to a more cautious appreciation of the long-term. Such an outlook is built-in to the DOTS technology, demonstrating that to be ‘future proof’ a technology need not only withstand environmental challenges, such as flooding or extreme temperature change, but must also be ‘innovation proof’ by being immune to the development of new technologies. As John Lafferty writes, the license bought with the product ‘would also mandate full backward compatibility to Generation Zero, achievable since readers capable of reading greater data densities should have no trouble reading lower density information.’ DOTS also do not use propriety codecs, as Chris Castaneda reports, ‘the company’s plan is to license the DOTS technology to manufacturers, who would develop and sell it as a non-proprietary system.’ Nor do they require specialist machines to be read. With breathtaking simplicity, ‘data can be recovered with a light and a lens.’

It would be wrong to assume that Group 47’s development of DOTS is not driven by commercial interests – it clearly is. DOTS do however seem to solve many of the real problems that currently afflict the responsible and long-term management of digital information. It will be interesting to see if the technology is adopted and by who. Watch this space!

* According to a 2011 Enterprise Strategy Group Archive TCO Study

Posted by debra in Audio Tape, Video Tape, 0 comments

Digital Preservation – Establishing Standards and Challenges for 2014

2014 will no doubt present a year of new challenges for those involved in digital preservation. A key issue remains the sustainability of digitisation practices within a world yet to establish firm standards and guidelines. Creating lasting procedures capable of working across varied and international institutions would bring some much needed stability to a profession often characterized by permanent change and innovation.

In 1969 The EIAJ-1 video tape was developed by the Electronic Industries Association of Japan. It was the first standardized format for industrial/non-broadcast video tape recording. Once implemented it enabled video tapes to be played on machines made by different manufacturers and it helped to make video use cheaper and more widespread, particularly within a domestic context.

Close up of tape machine on the 'play', 'stop', 'rewind' button

The introduction of standards in the digitisation world would of course have very little impact on the widespread use of digital technologies which are, in the west, largely ubiquitous. It would however make the business of digital preservation economically more efficient, simply because organisations would not be constantly adapting to change. For example, think of the costs involved in keeping up with rapid waves of technological transformation: updating equipment, migrating data and ensuring file integrity and operability are maintained are a few costly and time consuming examples of what this would entail.

Although increasingly sophisticated digital forensic technology can help to manage some of these processes, highly trained (real life!) people will still be needed to oversee any large-scale preservation project. Within such a context resource allocation will always have to account for these processes of adaptation. It has to be asked then: could this money, time and energy be practically harnessed in other, more efficient ways? The costs of non-standardisation becomes ever more pressing when we consider the amount of the digital data preserved by large institutions such as the British Library, whose digital collection is estimated to amass up to 5 petabytes (5000 terabytes) by 2020. This is not a simple case of updating your iphone to the next model, but an extremely complex and risky venture where the stakes are high. Do we really want to jeopardise rich forms cultural heritage in the name of technological progress?

The US-based National Digital Stewardship Alliance (NDSA) National Agenda for Digital Stewardship 2014 echoes such a sentiment. They argue that ‘the need for integration, interoperability, portability, and related standards and protocols stands out as a theme across all of these areas of infrastructure development’ (3). The executive summary also stresses the negative impact rapid technological change can create, and the need to ‘coordinate to develop comprehensive coverage on critical standards bodies, and promote systematic community monitoring of technology changes relevant to digital preservation.’ (2)

File Format Action Plans

One step on the way to more secure standards is the establishment of File Format Action Plans, a practice which is being increasingly recommended by US institutions. The idea behind developing a file format action plan is to create a directory of file types that are in regular use by people in their day to day lives and by institutions. Getting it all down on paper can help us track what may be described as the implicit user-standards of digital culture. This is the basic idea behind Parsimonious Preservation, discussed on the blog last year: that through observing trends in file use we may come to the conclusion that the best preservation policy is to leave data well alone since in practice files don’t seem to change that much, rather than risk the integrity of information via constant intervention.

As Lee Nilsson, who is currently working as a National Digital Stewardship Resident at the US Library of Congress writes, ‘specific file format action plans are not very common’, and when created are often subject to constant revision. Nevertheless he argues that devising action plans can ‘be more than just an “analysis of risk.” It could contain actionable information about software and formats which could be a major resource for the busy data manager.’

Other Preservation Challenges

Analogue to Digital Converter close up What are the other main challenges facing ‘digital stewards’ in 2014? In a world of exponential information growth, making decisions about what we keep and what we don’t becomes ever more pressing. When whole collections cannot be preserved digital curators are increasingly called upon to select material deemed representative and relevant. How is it possible to know now what material needs to be preserve for posterity? What values inform our decision making?

To take an example from our work at Great Bear: we often receive tapes from artists who have achieved little or no commercial success in their life times, but whose work is often of great quality and can tell us volumes about a particular community or musical style. How does such work stand up against commercially successful recordings? Which one is more valuable? The music that millions of people bought and enjoyed or the music that no one has ever heard?

Ultimately these questions will come to occupy a central concern for digital stewards of audio data, particularly with the explosion of born-digital music cultures which have enabled communities of informal and often non-commercial music makers to proliferate. How is it possible to know in advance what material will be valuable for people 20, 50 or 100 years from now? These are very difficult, if not impossible questions for large institutions to grapple with, and take responsibility for. Which is why, as members of a digital information management society, it is necessary to empower ourselves with relevant information so we can make considered decisions about our own personal archives.

A final point to stress is that among the ‘areas of concern’ for digital preservation cited by the NDSA, moving image and recorded sound figure highly, alongside other born-digital content such as electronic records, web and social media. Magnetic tape collections remain high risk and it is highly recommended that you migrate this content to a digital format as soon as possible. While digitisation certainly creates many problems as detailed above, magnetic tape is also threatened by physical deterioration and its own obsolescence challenges, in particular finding working machines to play back tape on. The simple truth is, if you want to access material in your tape collections it needs now to be stored in a resilient digital format. We can help, and offer other advice relating to digital information management, so don’t hesitate to get in touch.

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End of year thank yous to our customers

What a year it has been in the life of Greatbear Analogue and Digital Media. As always the material customers have sent us to digitise has been fascinating and diverse, both in terms of the recordings themselves and the technical challenges presented in the transfer process. At the end of a busy year we want to take this opportunity to thank our customers for sending us their valuable tape collections, which over the course of 2013 has amounted to a whopping 900 hours of digitised material.

We feel very honoured to play a part in preserving personal and institutional archives that are often incredibly rare, unique and, more often than not, very entertaining. It is a fairly regular occurrence in the Great Bear Studio to have radio jingles from the 60s, oral histories of war veterans, recordings of family get-togethers and video documentation of avant-garde 1970s art experiments simultaneously migrating in a vibrant melee of digitisation.

Throughout the year we have been transported to a breathtaking array of places and situations via the ‘mysterious little reddish-brown ribbon.’ Spoken word has featured heavily, with highlights including Brian Pimm-Smith‘s recordings of his drive across the Sahara desert, Pilot Officer Edwin Aldridge ‘Finn’ Haddock’s memories of World-War Two, and poet Paul Roche reading his translation of Sophocles’ Antigone.

We have also received a large amount of rare or ‘lost’ audio recordings through which we have encountered unique moments in popular music history. These include live recordings from the Couriers Folk Club in Leicester, demo tapes from artists who achieved niche success like 80s John Peel favourites BOB, and large archives of prolific but unknown songwriters such as the late Jack Hollingshead, who was briefly signed to the Beatles’ Apple label in the 1960s. We always have a steady stream of tapes from Bristol Archive Records, who continue to acquire rare recordings from bands active in the UK’s reggae and post-punk scenes.  We have also migrated VHS footage of local band Meet Your Feet from the early 1990s.

Rack of three digital multi-track machines On our blog we have delved into the wonderful world of digital preservation and information management, discussing issues such as ‘parsimonious preservation‘ which is advocated by the National Archives, as well as processes such as migration, normalisation and emulation. Our research suggests that there is still no ‘one-size-fits-all’ strategy in place for digital information management, and we will continue to monitor the debates and emerging practices in this field in the coming year. Migrating analogue and digital tapes to digital files remains strongly recommended for access and preservation reasons, with some experts bookmarking 15 April 2023 as the date when obsolescence for many formats will come into full effect.

We have been developing the blog into a source of information and advice for our customers, particularly relating to issues such as copyright and compression/ digital format delivery. We hope you have found it useful!

While the world is facing a growing electronic waste crisis, Great Bear is doing its bit to buck the trend by recycling old domestic and professional tape machines. In 2013 we have acquired over 20 ‘new’ old analogue and digital video machines. This has included early 70s video cassette domestic machines such as the N1502, up to the most recent obsolete formats such as Digital Betacam. We are always looking for old machines, both working and not working, so do get in touch if your spring clean involves ridding yourself of obsolete tape machines!

Our collection of test equipment is also growing as we acquire more wave form monitors, rare time-based correctors and vectorscopes. In audio preservation we’ve invested heavily in early digital audio machines such as multi-track DTRS and ADAT machines which are rapidly becoming obsolete.

We are very much looking forward to new challenges in 2014 as we help more people migrate their tape-based collections to digital formats. We are particularly keen to develop our work with larger archives and memory institutions, and can offer consultation on technical issues that arise from planning and delivering a large-scale digitisation project, so please do get in touch if you want to benefit from our knowledge and experience.

Once again a big thank you from us at Greatbear, and we hope to hear from you in the new year.

Posted by debra in Audio Tape, Video Tape, 0 comments

Jack Hollingshead’s lost Apple recordings on reel-to-reel tape

Digital technologies have helped to salvage all manner of ‘lost’ or ‘forgotten’ recordings. Whole record labels, from the recently featured Bristol Archive Records to institutional collections like Smithsonian Folkways, are based on the principle of making ‘hard to access’ recordings available in digital form.

A box crammed with dusty reel-to-reel tapes of different sizes

Occasionally we get such rare recordings in the Greatbear studio, and we are happy to turn the signal from analogue to digital so the music can be heard by new audiences. Last week we were sent a particularly interesting collection of tapes: a box of nearly 40 3”-10.5” reel to reel tapes from the songwriter and artist Jack Hollingshead, who sadly passed away in March 2013. The tapes are in good condition, although the spools are pretty dirty, most probably from being stored under the bed or at the back of a cupboard, as these things often are! Jack’s tape came to our attention after a phone call from the writer Stefan Granados, who wanted to arrange for a few songs to be digitised for a research project he is doing focused around the Beatles’ Apple Records company.

The Beatles set up Apple Records in 1968 as an outlet for their own and emerging artists’ recordings. Well known performers who were signed to Apple included Mary Hopkin, Ravi Shankar, James Taylor and many others. But there were also a number of artists who recorded sessions with Apple, but for one reason or another, their music was never released on the label. This is what happened to Jack’s music. Jack’s Apple sessions are psychedelic pop-folk songs with striking melodies, song cousins of drowsy Beatles hits like ‘Across the Universe’. He recorded seven songs in total, which we received on magnetic tape and acetate disc, the test cut of the recording that would have been printed on vinyl. We digitised from the magnetic tape because the disc was in fairly poor condition and we didn’t know how many times the disc had been played.

Listen to ‘Vote for ME’ by Jack Hollingshead

Jack Hollingshead_Acetate_Angle

 

It wasn’t the first time that Jack’s work had aroused record company interest. When he was 16 he signed a contract with Aberbach publishers. Like his experience with Apple a few years later, nothing came of the sessions, and because the companies owned the recordings, he was not able to release them independently.

Jack soon became very frustrated by the record industry in the late 1960s and decided he would do it himself. This was ten years before home recording became widely accessible, so it was not easy, either financially or technically.

In the 1970s a series of serious accidents, and a spell in prison, proved to be disruptive for his musical career. Jack’s prison sentence, received for growing marijuana he was using for medical pain relief purposes, was however fairly positive. It gave him time to focus on playing guitar and he wrote his best songs while incarcerated.

Jack Hollingshead_acetate_back

The back of a test acetate is grooveless

He continued to write and record music throughout his life, and there is a significant amount of material that Trina Grygiel, who is responsible for managing Jack’s estate, is determined to organise and release in his memory.

Jack was also prodigiously talented artist in other mediums, and turned his hand to puppet making, wax painting, gardening and property restoration. His obituary described him as a ‘perfectionist, in all his artistic, creative and practical endeavours he would settle for nothing less.’

Posted by debra in Audio Tape, 0 comments