MP3

The ease and speed of downloading MP3 files revolutionized how people buy, listen to, and profit from music.

MP3s made it easy to purchase songs individually and cheaply (or trade them—often illegally). Portable devices let listeners carry entire collections with them.

But as online inventories grew, brick-and-mortar stores began to vanish, along with the industry’s traditional business model.

Traditional music shops offered limited inventories and hours. Few let you sample music before buying. Online stores, by contrast, have virtually infinite capacity. Popular or obscure, recent or vintage—it’s a click away, 24/7

Yet online shopping does limit one thing: chance discoveries, whether from a clerk’s quirky advice or eye-catching album covers

Downloadable music challenged the music industry. Then transformed it.

The challenge came from the ease of sharing (and stealing!) music, bypassing retailers. The transformation came from Apple’s sleek iPod players and iTunes store, which made Apple the world’s biggest music vendor…and squeezed publishers’ profits and artists’ royalties

Travel is easier when you pack light, taking along only what you’ll use. MP3s use a similar principle.

In the pre-internet era, when huge file sizes didn’t matter, CDs offered high fidelity and hours of music. MP3s, by contrast, “pack light.” They discard tones too high or low for human ears to hear, or that are masked by other sounds.

MP3s fool our ears by discarding sounds that enter our ears…yet aren’t heard.

Hearing combines physical structures that capture sound waves, and neural systems that interpret them. Our brains suppress sounds that follow each other too closely, or are drowned out by louder sounds. MP3s exploit these psychoacoustic principles.

Your favorite delicious dish probably includes ingredients you don’t notice individually, yet which enhance the overall flavor. Is the same true of audio recordings?

MP3's “lossy compression” discards tones you’re unaware of. But some audiophiles argue that they’re not completely inaudible and that they enrich the overall sound.

Could digital phone lines become a new medium to deliver on-demand music?

Karlheinz Brandenburg’s thesis advisor hoped so. In 1986 he challenged the German engineering student to compress music files sufficiently for delivery over digital phone lines. A week later, Brandenburg had developed the code that blossomed into MP3.

While refining his MP3 code, Karlheinz Brandenburg heard Suzanne Vega’s hit “Tom’s Diner” playing on the radio. He realized that this a cappella song would be nearly impossible to compress successfully. Nearly.

“Tom’s Diner,” Brandenburg’s worst-case scenario, became his test song and Vega herself got dubbed the “Mother of the MP3.”

Downloadable? Great. Stolen? Not so great—at least for music publishers.

Paralyzed by piracy fears, publishers couldn’t agree on a standard for online sales. Services like Napster.com filled the gap, letting users share millions of songs for free.

After industry lawsuits buried Napster, Apple’s iTunes satisfied demand with an affordable, legal alternative.