TechnoPop: The History of Technology In Popular Music is an excellent series airing on NPR that discusses the significant impact of technological innovation on how music is composed, played, recorded, distributed and promoted. You can find audio, text and pictures from the series at the National Public Radio web site.

Here is part of the series description, by NPR cultural correspondent Robert Karr:

When Thomas Edison invented the phonograph in 1877, he accidentally invented the music industry. The last thing on the inventor's mind was using his new device to record music. He figured there was a better market in dictation equipment that could record contracts and business letters. Recordings don't lie, he said.

In fact, he resisted music as the "killer app" for the new technology, until competitors proved there was a market for it — a big one.

So big, in fact, that nobody who made or listened to music could ignore the phonograph and the industry it created. Songwriters shortened their compositions so they'd fit on one side of a 78 rpm record. Singers worked on their projection and enunciation so that the primitive recording technology would render their voices at least halfway decently. And fans got into more kinds of music than many had ever known even existed.

Everyone's understanding of music changed completely. Piano sales fell. Music lovers spent less time getting together for hootenannies on the porch or jam sessions around a piano. They gathered around the horns of their Victrolas, leaning with their ears cocked like Victor's spokesdog, Nipper.

Since then, technological innovations have repeatedly altered the sound of popular music, and regularly changed the way listeners acquire it, listen to it, and share it with others. TechnoPop is the story of those changes.

New technologies make their mark on music in two basic ways: They alter the sound of pop — what musicians can make and listeners can hear — or they change the economics of recording and distributing music. For the past century, a new technology has changed the music industry every quarter century or so.

This morning they aired part four, which described the advent of the LP and FM radio and how these inventions created the opportunity to make "alternative" music (rock, folk, world music, blues) available to mass audiences.