Making Music Accessible
This week, our guest columnist is David Martinelli, the Ethnomusicology Archive's recording technician. David also oversees the Ethnomusicology and Systematic Musicology Laboratory, documents departmental events (which become part of the Archive's Departmental collection), and seems to provide audiovisual assistance to almost everyone in HASOM. David is Schoenberg Music Building's own man in black. And David is an accomplished musician. So, without further ado... David Martinelli. -- Maureen
Over the years, sound recordings have existed in a variety of physical formats. Today, sound recordings are primarily computer files, in various formats such as WAV or MP3. New recordings are made directly to computer, while commercial recordings are either ripped from CDs or downloaded from the internet. Once a sound recording becomes a computer file, it can be moved easily from computer to computer and copied infinitely. Music collections that once filled storage cabinets can now be put on a palm-sized hard drive. Once these files are imported into a music player like iTunes or Windows Media Player, they can be arranged and sorted however the user wishes.
However, anything recorded using an older technology must now be converted into a computer file to be easily accessible. This is what I do at the Ethnomusicology Archive. This conversion process is called digitizing. The Archive collects both field recordings and commercial recordings. The field recordings are most often in reel to reel tape or cassette formats, while the commercial recordings are usually LP or cassette. All of these formats are analog, so the signal from the playback machine goes into the A/D converter, which is connected via SPDIF to the computer’s sound card. The signal path is as direct as possible, there are no patch bays or outboard gear used. The recording software used is Steinberg’s Wavelab. The only adjustment I make is setting the output level of the tape player before digitizing. If this level is initially set at too low or too high a level, I have to readjust it and start over. I do not make any changes to the signal during recording, and do not do any processing of the file after it is recorded.
The most challenging of these formats is reel to reel tape. Fortunately the archive has several machines that will play these tapes, as these machines are no longer easy to find. The tapes themselves often present challenges as well. Some tapes exhibit a condition called sticky-shed, where the tape actually sticks to itself while playing, creating a loud squealing noise and leaving residue on the tape machine. Sticky shed can usually be cured using a process called baking, which consists of drying out the tape for several hours using a food dehydrator. A more serious problem is when the tape actually falls apart while playing. The Archive recently received one collection where the tapes did this, and we are trying out an experimental procedure to see if these tapes can be salvaged.
The recording format of the tape must also be determined. Reel to reel tapes can be recorded at a variety of speeds, from the professional 30 ips (inches per second) standard, to a lo-fi 15/16 ips (the faster the tape speed, the better the sound quality). The archive’s tape machines can play any speed except 30 ips. The track format can vary, the most common being full track mono (a mono recording that plays in one direction), half track mono (two mono signals going in opposite directions), or quarter track stereo (two stereo signals going in opposite directions). It is possible for a single tape to have been recorded using a variety of speeds and track formats, the specifics of which are rarely indicated in the documentation. The only way to know what you have is to listen to it, and be on the lookout for anything unusual. For example, if you are digitizing a tape of an interview, and you hear music at the same time, does this mean that there are two different signals being heard simultaneously (which would happen if you listen to a quarter track tape using the half track playback setting), or does it mean that the radio was playing in the background while the interview was being recorded?
Cassettes are more straightforward to digitize, and rarely present the technical challenges of reel to reel. There are still some cassette players that are commercially available, so the equipment is not that difficult to come by.
Once the tapes are digitized, whatever documentation that was included with the tapes is entered into a computer database called SCREAD. Sometimes the documentation is very thorough, and other times there is no documentation at all. For the latter, I will usually put in SCREAD something like “Side 1: Several unidentified songs”. Technical details about the tapes (speed, track format, reel size) are included, and any anomalies (hums, distortion) are noted.
The files are then stored on hard drives and backed up to DVD-Rs. Since we record at 96/24, file sizes are larger than the 44.1/16 CD standard, and much larger than MP3s, resulting in stacks of DVD discs and hard drives (hopefully the latter will soon be replaced by a server). We do not digitize to MP3 as this is a lossy form of compression and not acceptable for archiving. Some collections are made accessible online, others are given to the collector or repatriated to the communities where they were recorded. The rest will remain on the hard drives (or server) until you come in to listen to them.