The crack team of Paul White and Hugh Robjohns have travelled the world solving readers' problems. Here they down the Hob Nobs and answer some of your recording queries in our Q&A mini-series, Sound Advice
Hugh: The key aspects of an archiving system are that it is stable, and that it uses a format that can be accessed easily. Historically, we know that shellac and vinyl records are pretty stable for at least 100 and 50 years, respectively, and the technology needed to replay them is straightforward. Optical sound tracks on film have survived extremely well, while analogue tape hasn't proved quite so robust in some specific cases (notably involving particular kinds of tape binder used in the '70s and '80s).
Paul: But with most music these days recorded digitally, we have to think about digital backups. The good news is that since our technology is derived from the computer industry, there are plenty of off-the-shelf options for data archiving. The fundamental audio data formats — WAV, and AIFF (and their 64-bit variants) — are very simple and there should be no problem accessing the raw audio in decades or even centuries.
Hugh: The bad news is that the project data formats used by the numerous different sequencers and DAWs to log the production processes (mix data, plug-in settings, MIDI-control data and so forth) are bespoke, complex, and tend to change with new software editions. With this in mind, it is wise to save the source audio files both with and without plug-in effects so that you have the option of recreating the mix as it was or starting afresh with new effects. Ideally these audio files should be saved at the highest possible resolution as data files, not as 16-bit audio CDs, which have relatively poor error correction.
Paul: But what to do with the data? There is a popular maxim that computer data doesn't really exist unless it is stored in at least three different places at the same time — preferably with at least one being off site in case fire, flood or some other disaster causes the loss of the primary storage. We probably all know someone who has suffered a catastrophic loss of data through a drive failure, even if we have been fortunate enough not to have suffered ourselves. So multiple backups are essential.
Hugh: The risk of data loss can be lessened further by using RAID arrays — multiple hard drives configured so that the data is shared across them in such a way that, should a drive fail, it can be replaced and the data reconstructed (automatically) without loss. Terabyte RAID arrays can be bought now for about the same as a half-decent guitar or set of active monitors.
Paul: However, hard drives aren't immune to failure, and the worst thing you can do to a disk drive — whether it's part of a RAID array or not — is store it on a shelf somewhere. Drives need to spin to keep them alive, and if left idle and static for long periods the platter and motor bearings have been known to fail. Data recovery experts can often retrieve the data by disassembling the drive and repairing it, but it's not something you should rely on! Far better to keep using the discs regularly, and to copy the data routinely to new discs (or other storage formats) every couple of years.
Hugh: There are other storage options beside hard disk, of course — although most are slower and require some level of manual intervention. Recordable discs like CD-R and DVDÂ±R are cheap and easy to use, but their long term stability is unproven. Re-recordable formats like CD-RW and DVDÂ±RW are better long-term bets from a chemistry point of view, but even so it would be a wise precaution to burn multiple copies on different media brands.
Paul: Keep CD- and DVD-based media in the dark in a moderate environment with no extremes of temperature and humidity. A shoe box on the top shelf of your wardrobe is probably as good a place as any in the home studio. You should also make sure all the necessary documentation is included and that the discs themselves are properly labelled. With hard drive backups, a text information file is the simplest way of keeping track of what you have.
Hugh: Solid-state storage is quickly gaining in data capacity and robustness, but there are too many scare stories of random data loss around to consider this a reliable long-term archive medium at the moment. So bearing all that in mind, I would favour storage to multiple hard disks, ideally with at least one being a RAID array. Copy the data between hard drives periodically, and make sure some copies are stored on a separate site.
Paul: And most important of all, once you have made an archive copy, check that it really can be retrieved successfully. There's nothing more upsetting than dismissing the shock of a dead hard drive with the confidence that everything is safely backed up elsewhere, only to then find that the archives can't be accessed after all!