原创 How it used to be: Magnetic wire recorders

If I were to ask you to briefly sum up the history of sound recording, I'm sure you would begin with something like Thomas Edison's cylinder-based phonograph circa 1878 as illustrated below.

A cylinder-based phonograph

The phonograph was a device with a cylinder covered with an impressionable material such as tin foil, lead, or wax on which a stylus etched grooves. The depth of the grooves made by the stylus corresponded to change in air pressure created by the original sound. The recording could be played back by tracing a needle through the groove and amplifying, through mechanical means, the resulting vibrations. One disadvantage of the early phonographs was the difficulty of mass-producing copies of the recorded cylinders.

The next major development in sound recording was the gramophone, which was patented by Emile Berliner in 1887.

A disk-based gramophone

The gramophone imprinted grooves on the flat side of a disc rather than the outside of a cylinder. Instead of recording by varying the depth of the groove (vertically), as with the phonograph, the vibration of the recording stylus was across the width of the track (horizontally) and the depth of the groove remained constant. This made gramophone records a lot easier to reproduce as compared to their phonographic cylinder cousins.

The first gramophones were all mechanical; the sound was captured and played-back by mechanical means, while the discs were turned by hand or ? most commonly ? by a hand-wound clockwork motor. Later, the advent of electrical recording techniques made it possible to use microphones to capture the sound, amplifiers and loudspeakers to play it back, and electric motors to spin the platter.

And what came next? Well, a lot of people would suggest the Magnetic Tape recorder. The world's first practical magnetic tape recorder, the 'K1', was created by engineers at AEG and was demonstrated in 1935.

An early magnetic tape recorder.

And, of course, we could now wander off into the realms of Compact Cassette, which was introduced to the market circa 1963; Eight-Track (also known as Eight-Track Cartridge, Eight-Track Tape, or Stereo 8), which was created in 1964 (when I was a kid my older cousins had hundreds of Eight-Track Cartridges); and the Compact Disc (CD), which became available to the public circa the early 1980s.

But wait! We've missed something. What a lot of folks don't know is that prior to magnetic tape recorders there were magnetic wire recorders. In this case, a wire is pulled rapidly across a recording head, which magnetizes each point along the wire in accordance with the intensity and polarity of an electrical audio signal. This actually makes a lot of sense when you come to think about it. In those days of yore, many companies had become expert in creating steel wire and it would be relatively easy to pull wire from one spool to another across a recording / playback head.

The first magnetic wire recorder was created in 1899 by a Danish Engineer called Valdemar Poulsen (1869-1942). Commercial magnetic wire recorders for dictation and telephone recording were made almost continuously from the 1920s onwards, but the real heyday of wire recording was in the 1940s through to the mid-1950s.

A Peirce 55-B dictation wire recorder from 1945

To be perfectly honest, I'd never heard of magnetic wire recorders myself, until an English guy told me about them around a year ago. Actually, this is a really cool story, which I present below as it was presented to me:

When I was a boy I heard stories of some recordings that my grandfather made of his family, including the voices of my great grandparents, and even my mother as a young child...

A few years ago I found the recordings. They were made on steel wire in the late '40s and early '50s, before tape recording had been introduced to the domestic market. In fact my grandfather had designed and built his own wire recorder, and his own special wire spools for it.

The original recorder is long gone, which made the task of recovering the recordings all the more interesting! But I decided to have a go, and embarked on a fascinating project to learn about wire recording, and to adapt an old Webster-Chicago wire recorder to play back the spools.

Having now experienced playback of hair-thin steel wire, racing along at 2 feet per second, it makes me very grateful for CDs and MP3s! It is a pretty hazardous affair, especially when the finely tuned bailing mechanism glitches, and spills wire at high speed within inches of poorly isolated high voltages!

I doubt many people will remember the days before tape recorders, especially here in the UK where wire recorders never quite seemed to catch on as they did in the US. But there are still a few working recorders in existence and a few people who can recover recordings from old wire spools. The recordings do very slowly degrade over the years, so if you have any spools gathering dust in the attic, now is the time to get them out and get them turned into MP3s ? before it is too late!

Click Here to see photos and a description of this project.

I think this is a truly amazing tale. Can you imagine what it would be like to be able to listen to your mother chatting away when she was a young child? My mother tells me that they didn't even get electricity into their house until around 1943, and they certainly couldn't afford something like a magnetic wire recorder, so her voice has been lost forever (well, her young voice has been lost ? her current voice is still going [and going and going and going] strong :-)

It must have been a real thrill for this guy when he first got his home-made machine working and could listen to those voices from so long ago. This really does quality as a "blast from the past"!