it was an era that was not yet electronic, the heyday of mechanical civilization and the early days of electrical engineering.

to better describe that era, imagine the American TV series Westworld, which was about 100 years ago.

and the cool techs I'm talking about 100 years ago actually appeared at the beginning of Westworld, the one that hinted that artificial intelligence was going its own way-automatically playing the piano, to be exact, was invented 120 years ago at the end of the 19th century.

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We all know that the earliest computer storage is "perforated paper tape", with holes is 1, non-hole is 0, so that binary information is recorded, and then entered into the computer through photoelectric scanning.

but there are still decades to go before photoelectric scanning was invented at the end of the 19th century.

how to control piano performance for paper rolls with holes?

the earliest way to make self-made music rolls

in the early 19th century required a recorded piano. When the pianist played on this "mother piano", each key triggered an air valve, which hit the corresponding hammer, then hammered the piano roll on the carbon paper and punched the marks.

later in the middle and late 20th century, it was processed by a computer. The "electronic piano" could play the notes. After the computer converted the notes into data, they were directly associated with the punching machine. The longer each perforation, the longer the delay of a note.

Paper Tape controls Piano playing

when the paper roll rotates through the selfie piano, there will be a stream of air inside the piano, which blows into the hole of the paper roll. After the air passes through the hole, it triggers the corresponding air valve, which drives the solenoid installed at the bottom of the keyboard, which is used as a power component to push the hammer of the piano to hit the strings to make music.

in this way, the performance of the whole "piano self-playing system" is exactly the same as that of a real person playing the piano. And because the number of paper roll holes is not limited by the ten fingers of the hand, the scale and range of the piano can be brought into full play.

so automatic piano is favored by innovative modern composers. Rachmaninov, Debussy, Mahler, Gershwin and Richard Strauss have all written music for this instrument and made paper tape for automatic piano performance.

GIF screenshot from

Discovery "How it\'s Made" S13E03

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