Transcribing a Recording by Computer
The standard hi-fi methods of copying music for your own use include cassette recording, DAT, and now CD-R or CD-RW. With the help of a computer you can go considerably further by editing the music (cutting out scratches, for example, in old vinyl-disc recordings) or by recording to MP3. The following paragraphs summarize the methods used for computer manipulation of sound for any digital form of recording, mainly CD-R and MP3. The computer must contain a sound card with a A-D converter that is up to CD quality standards, and if you want to record your own CDs you will also need a CD writing drive with appropriate software such as Adaptec Easy CD Creator. For MP3 files you will need software such as Winamp.
This is not intended to be an exhaustive guide to using a computer for manipulating audio files, as space does not permit a thorough treatment of such a large topic. If you are an experienced user of a PC computer, this is a guide to its use for audio work, and if you do not use a computer, it is a guide to what you are missing.
The first step to the creation of either an MP3 file or a CD-R disc is to extract music tracks and digitize them in an uncompressed format using a type of file distinguished by the extension letters WAV, hence called a WAV file. Some software will carry out this action automatically, reading in the audio tracks and converting to MP3 or to CD-R without leaving a WAV file behind on the computer’s hard disc. As applied to a CD as source, this action is often termed CD ripping. Whether you are aware of it or not, WAV files are always created as an intermediary, and it’s an advantage if you can store them in the computer, check them, and possibly edit them before you save them in MP3 or CD-R format and delete the WAV versions.
You are not obliged to use a CD as a source, though, and many users of MP3 or CD-R are more concerned with taking tracks from old 78s, from LPs, or from cassettes, even from radio or private recordings. Remember, however, that no matter what source you use, working at CD quality will require disc space on your computer of around 700 Mbytes for a full CD.
If you are using a CD as your source, you must use the digital output from the CD drive or deck. It is certainly possible to connect the audio output of a CD deck to the line input of the sound card on your computer and to create WAV files in this way, but this sacrifices quality. Most computers fitted with a CD writer will also have a fast CD reader, allowing you to read digital data at 36 times (or more) the normal recording speed. This also ensures that the digital output of the CD is used.
● The normal setting on most CD copying software gives you a 2-s gap between tracks when you are working in “normal mode,” which is track-at-once. If you specify disc-at-once, you will not get any added gaps between the tracks, so if you want extra time between the tracks you have to edit the WAV files so as to include
silent intervals. If your list of tracks shows separate files, the recording will always place track markers so that you can move to any track in the usual way.
You can also create WAV files using any other audio source, such as 78s, LPs, cassettes, and DAT tapes. The conversion quality will be lower, because these sources all provide analogue signals of varying quality and signal level. You will need to do a few experiments with connections and signal levels, and this is why it is such an advantage to make a separate conversion to WAV, because you can play back a WAV file that is stored in the computer without the need to waste space on CD-R with an unsatisfactory recording or to make a useless MP3 file. You must, incidentally, use a modern 16-bit sound card—do not try to work with analogue to digital conversions using the older 8- bit type of card. Any computer that is fast enough to cope with audio work will almost certainly be fitted with a 16-bit card. Remember, however, that the quality of A-D conversion may not be as good as you would like.
The usual advice is to connect the audio output from the source device to the line- in connector, usually a 3.5-mm stereo jack socket, on the sound card of the computer. Depending on the sound card that you are using, you may find that the line- in is much too insensitive and that you hear virtually nothing when you replay the WAV file. The only option, unless you have a spare preamp to connect between the signal source and the sound card, is to use the MIC input. This, by contrast, may be too sensitive, leading to overloading.
The important thing is to try this out with a short piece of music before you start making any recordings to CD-R or MP3. The typical software that you will be using for creating the WAV file is Creative Wave Studio, which permits you to make a short recording to test sound levels. Using the software control panel illustrated in Figure 21.3, you can adjust
the level of the signal on its way to the WAV file, but this will not help if the input stage of the sound card is overloading.
You can then play this back, either through the loudspeakers of the computer or by way of a connection to a hi-fi system, using the output jack of the sound card. The same software, incidentally, allows you to edit a WAV file to remove gaps and, after some practice, unwanted sounds, such as scratches and thumps.
You may need to make some setting-up steps, and although some software will do this almost automatically you should check the following:
● Record options must be set to stereo, 8 or 16 bits, 44.1 kHz sampling rate. Use 16-bit data for CD or other high-quality sources.
● Type in the name that you want to use for the WAV file and a folder (directory) on the computer’s hard disc where you want to store the file. The usual pattern is to select a name that will describe the music, such as Beethoven 5 Symphony, and store it where you can accommodate a large file of up to 700 Mbytes.
● Check that you have set the recording levels correctly.
● Click the Record icon on the screen and start the source playing. The screen display will probably show the progress of the recording.
You can make your recording one track at a time, making a separate WAV file from each track, or you can make a single file of the whole input. A single file uses less space (because it eliminates the “overhead” involved in making a separate file for each track), but it makes finding individual tracks (if you need to) more difficult. Software products such as LP Ripper or Adaptek Spin Doctor will work on the WAV file and separate out the tracks for you, whereas others will edit the WAV files manually.
The topic of editing a WAV file is too specialized for this book, but the principles are not difficult, and some practice with a short file is more useful than any amount of text instruction.