1935

Tape Recording

Fritz Pfleumer (1881–1945)

Think how useful it is to be able to record sound. Today we make audio and video recordings at the touch of a button on our smart phones, and we do it constantly.

The popularity of recording began nearly the instant the technology was brought to market in 1888. The original technology—wax cylinders and a needle—made it possible for people to record and play back sounds. What really took off was prerecorded music, and it has been popular ever since.

Tape recording started in 1935 in Germany with the invention of the first practical tape recorder, the AEG Magnetophon K1, which was developed by German electronics company AEG and based on the invention of magnetic tape by engineer Fritz Pfleumer. A coating of ferric oxide on a thin plastic backing formed the tape, thousands of feet of which could fit on a real. A motor pulled the tape across a read-write head to another reel. A varying current in the head created a magnetic field to record onto the ferric oxide. Or the recording in the ferric oxide would create a small current in the head, which could then be amplified and heard. The initial systems were incredibly simple like this, yet they yielded very realistic recordings.

Once engineers had the basic technology of recording and playback nailed down, they morphed the technology in several different directions. The 8-track cartridge and then the compact cassette made tape much easier to use. Helical recording heads made video recording possible, and this morphed into VHS systems that allowed people to record TV shows and play movies at home. Computer tape drives were incredibly important in the 60s and 70s for data storage. Watch any older sci-fi film like Dr. Strangelove and spinning tape drives add a high-tech feel. Engineers improved the form factor to create floppy disks for computers as well. It is the same technology rendered onto a disk to make random access quicker. We even find short pieces of magnetic tape on the back of our credit cards.

Tape recording is a great demonstration of how engineers can take one technological idea and spin it off in many different directions.

SEE ALSO Hard Disk (1956), VHS Video Tape (1976).

The first practical tape recorder was developed in 1935; this model is from the late 1970s.