The problems with digital audio archives

ldbell15 by Zyada (cc) (from Flickr)
ldbell15 by Zyada (cc) (from Flickr)

A recent article in Rolling Stone (File Not Found: The Record Industry’s Digital Storage Crisis) laments the fact that digital recordings can go out of service due to format changes, plugin changes, and/or files not being readable (file not found).

In olden days, multi-track masters were recorded on audio tape and kept in vaults.  Audio tape formats never seemed to change or at least changed infrequently, and thus, re-usable years or decades after being recorded.  And the audio tape drives seemed to last forever.

Digital audio recordings on the other hand, are typically stored in book cases/file cabinets/drawers, on media that can easily become out-of-date technology (i.e., un-readable) and in digital formats that seem to change with every new version of software.

Consumer grade media doesn’t archive very well

The article talks about using hard drives for digital recordings and trying to read them decades after they were recorded.  I would be surprised if they still spin up (due to stiction) let alone still readable.  But even if these were CDs or DVDs, the lifetime of consumer grade media is not that long, maybe a couple of years at best, if treated well and if abused by writing on them or by bad handling, it’s considerably less than that.

Digital audio formats change frequently

The other problem with digital audio recordings is that formats go out of date.  I am no expert but let’s take Apple’s Garage Band as an example.  I would be surprised if 15 years down the line that a 2010 Garage Band session recorded today was readable/usable with Garage Band 2025, assuming it even existed.  Sounds like a long time but it’s probably nothing for popular music coming out today.

Solutions to digital audio media problems

Audio recordings must use archive grade media if it’s to survive for longer than 18-36 months.  I am aware of archive grade DVD disks but have never tested any, so cannot speak to their viability in this application.  However, for an interesting discussion on archive quality CD&DVD media see How to choose CD/DVD archival media. But, there are other alternatives.

Removable data center class archive media today includes magnetic tape, removable magnetic disks or removable MO disks.

  • Magnetic tape – LTO media vendors specify archive life on the order of 30 years, however this assumes a drive exists that can read the media.  The LTO consortium states that current generation drives will read back two generations (LTO-5 drive today reads LTO-4 and LTO-3 media) and write back one generation (LTO-5 drive can write on LTO-4 media [in LTO-4 format]).  With LTO generations coming every 2 years or so, it would only take 6 years for a LTO volume, recorded today to be unreadable by current drives.  Naturally, one could keep an old drive around but maintenance/service would no longer be available for it after a couple of years.  LTO drives are available from a number of vendors.
  • Magnetic disk – The RDX Storage Alliance claims a media archive life of 30 years but I wonder whether a RDX drive would exist that could read it and the other question is how archive life was validated. Today’s removable disk typically imitates a magnetic tape drive/format.  The most prominent removable disk vendor is ProStor Systems but there are others.
  • Magneto-optical (MO) media – Plasmon UDO claims a media life of 50+ years for their magneto-optical media.  UDO has been used for years to record check images, medical information and other data.  Nonetheless,  recently UDO technology has not been able to keep up with other digital archive solutions and have gained a pretty bad rap for usability problems.  However, they plan to release a new generation of UDO product line in 2010 which may shake things up if it arrives and can address their usability issues.

Finally, one could use non-removable, high density disk drives and migrate the audio data every 2-3 years to new generation disks.  This would keep the data readable and continuously accessible.  Modern storage systems with RAID and other advanced protection schemes can protect data from any single and potentially double drive failure but as drives age, their error rate goes up.  This is why the data needs to be moved to new disks periodically.  Naturally, this is more frequently than magnetic tape, but given disk drive usability and capacity gains, might make sense in certain applications.

As for removable USB sticks – unclear what the archive life is for these consumer devices but potentially some version that went after the archive market might make sense.  It would need to be robust, have a long archive life and be cheap enough to compete with all the above.  I just don’t see anything here yet.

Solutions to digital audio format problems

There needs to be an XML-like description of a master recording that reduces everything to a more self-defined level which describes the hierarchy of the recording, and provides object buckets for various audio tracks/assets.  Plugins that create special effects would need to convert their effects to something akin to a MPEG-like track that could be mixed with the other tracks, surrounded by meta-data describing where it starts, ends and other important info.

Baring that, some form of standardization on a master recording format would work.  Such a standard could be supported by all major recording tools and would allow a master recording to be exported and imported across software tools/versions.  As this format evolved, migration/conversion products could be supplied to upgrade old formats to new ones.

Another approach is to have some repository for current master audio recording formats.  As software packages go out of date/business, their recording format could be stored in some “format repository”, funded by the recording industry and maintained in perpetuity.  Plug-in use would need to be documented similarly.  With a repository like this around and “some amount” of coding, no master recording need be lost to out-of-date software formats.

Nonetheless, If your audio archive needs to be migrated periodically, it be a convenient time to upgrade the audio format as well.


I have written about these problems before in a more general sense (see Today’s data and the 1000 year archive) but the recording industry seems to be “leading edge” for these issues. When Producer T Bone Burnett testifies at a hearing that “Digital is a feeble storage medium” it’s time to step up and take action.

Digital storage is no more feeble than analog storage – they each have their strengths and weaknesses.  Analog storage has gone away because it couldn’t keep up with digital recording densities, pricing, and increased functionality.  Just because data is recorded digitally doesn’t mean it has to be impermanent, hard to read 15-35 years hence, or in formats that are no longer supported.  But it does take some careful thought on what storage media you use and on how you format your data.


CDs and DVDs longevity questioned

DVD-R read/write side (from
DVD-R read/write side (from

In a recent article from BBC on Should you store treasured data on (optical) disk the conclusion was that CDs and DVDs have significantly worse archive life than advertised or even suspected until recently.  The study done by the French National Centre for Scientific Research discovered that the reliability of a few optical disks was just over one year and most “rarely lasted longer than five to 10 years” although they were advertised to last significantly more.

There was not much detail in the BBC article and searching (in English) for the original research yielded nothing pertaining to the topic.   However, the article did say that the centre used accelerated life testing with heat, water vapor and light (standard IT industry practice) to determine point of failure and that products under the same brand had significant archive life variability due to multiple manufacturers.  They also stated that branding the discs might be impacting longevity as well. And that it appeared that the more than seven miles of (probably DVD) data recorded on the discs is deteriating faster than anticipated.

As a result, they suggested that data on optical disks should be copied every two to three years and maybe as time moves on, this can be done less frequently assuming optical disk lifespans improve.  Also important data should be spread across multiple storage formats.

The case for (IT) tape in video archives

Nonetheless, the article did mention that a 52 minute documentary typically requires about 500GB of high definition video to be recorded and at the moment that video is normally stored on data (tape) cassettes and hard drives.  In my experience these (video) tapes were specific to the recording equipment vendor, i.e. Panasonic, Sony, or others and as such, relatively expensive.  But nowadays, this data can also be stored on LTO or other IT tapes.  In contrast to the above, LTO tape has an archival storage life of around 30 years (depending on vendor) and can be had at reasonable cost.

Also, in the past I was aware of a number of TV broadcasters that had an archive of finished broadcasts residing only on DVDs.  They typically took one additional copy of a DVD and stored them both in their desks or file cabinets.  Many of these people will be very surprised when five years down the line, they go to access their archived broadcasts and find that they can no longer be read.  Of course, I have made the same mistake with my family video archive stored on DVDs.

Video archives whether of raw video or finished broadcasts require large capacity, sequentially accessed storage which seems ideal for automated LTO or other magnetic tape storage.  By using IT tape data storage for video archives, one can benefit from technology advances in density and throughput that happen every couple of years, benefit from volume manufacturing available to IT product manufacturers, and benefit from a significantly longer archive life.

Now if I can just find a USB LTO tape drive that works on the Mac for my home videos and family backups I would feel much better, …