4.13 Sound capture devices

In the past, the work of recording sound and music was carried out by professional recording studios. Before digital technology arrived, recordings were made by picking up sounds on a microphone which converted them to an analogue electrical signal. This signal was then transferred to another analogue medium, such as the grooves of a vinyl record or the changing patterns of metallic atoms on a magnetic tape.

At the start of the digital revolution, analogue to digital conversion, and the transfer of digitally encoded sound to compact discs, could only be accomplished with sophisticated and expensive equipment. Nowadays, many personal computers come ready equipped with A/D (analogue to digital) electronics built in, and with a drive for writing CDs. A range of new compression formats for sound and music, the most notable being MP3, are looking as if they might undermine the whole financial basis of the music recording industry. It is now easy to compress the contents of a CD to MP3 format, and post the file to a website for anyone in the world to download and write to a CD of their own – free. Recently, one such a website, named Napster, was ordered by a US court to cease operations, on grounds of breach of copyright. But Napster has many imitators, so the problem remains.