Tape Nostalgia Meets High-tech

Reading the magnetic states

Audio tapes store information in a layer of tiny magnetic particles—like little compass needles pointing either north or south. When the tape is recorded, their magnetic orientation is changed—the tape becomes magnetized, and the audio information is now physically stored in the orientation pattern. To play back this pattern, the tape is moved past a play head. As the magnetic field constantly changes through the pattern, a voltage is induced in the play head and an electrical signal is generated. This signal is amplified and converted into an acoustic signal.

Researchers are developing a technique that uses the special synchrotron X-ray light from the Swiss Light Source SLS to non-destructively digitize recordings from high-value historic audio tapes—including treasures from the Montreux Jazz Festival archive, such as a rare recording of the King of the Blues, B.B. King.

To achieve their goal, they have been collaborating with the Swiss National Sound Archives, which has produced custom-made reference recordings and provided audio engineering know-how. Now, a partnership with the Montreux Jazz Digital Project will help to further develop and test the method.

Nostalgia meets high-tech

Much of the audio world is physics and can be expressed in formulas and numbers. However, when it comes to concepts such as sound and the quality produced, the subjective aural experience is paramount. That is why Gliga works with experts like the Basel sound engineer and composer Daniel Dettwiler. Dettwiler is renowned for analog music processing. His studio is also home to a Studer A80, a tape machine that records and plays back magnetic audio tapes with high precision.