FOOD FOR THOUGHT: Whisper in my ear

So the other day I held the phone up to my ear with the speakerphone turned on and I realized that I could actually feel the air on my face as the person talked. This initially seemed creepy but eventually I came around to the idea that it’s not like the phone was breathing but the variances and vibrations were enough to move the air in a way I could feel. It made me think of speakers, which really are pretty nifty little inventions.

Who invented the speaker?

The funny thing is, we don’t really talk about the invention of the speaker. The speaker came along in the mid-to-late 1800s when technology was exploding. The telegraph made it possible for people to communicate over long distances for the first time ever. And this meant that scientists could build off each other’s work quickly. Or, at least what passed for quickly back then.

Speakers were seen as an important part of the technology of the telephone. A lot of people were working on perfecting a telephone in the 1860s. Of course we are all told it was Alexander Graham Bell who figured it out first but that may not be right.  Regardless of who got it right first, everyone knew a telephone had a couple of basic parts. You needed a microphone and a speaker, and some way to get those signals to another location without them getting lost in the noise. Because you needed all three, we don’t talk too much about the invention of any of them. At least, not until all three were finished.

What is a speaker anyway?

A microphone and a speaker are basically the same thing. The construction is different enough that a speaker makes a poor microphone and a microphone makes a poor speaker. But the idea is the same either way. There’s a basic translation between the vibrations of a thin membrane and a magnet. With a microphone, the magnet moves because the membrane vibrates, and with a speaker the membrane vibrates because the magnet moves. Either way, it’s a very elegant way of translating movement into electricity. It’s so elegant that a really good speaker can reproduce the most delicate nuance.

How we got here

See, the world today is mostly digital. It’s kind of easy to think about how computers deal with sounds. It’s all math. Each slice of time represents a specific frequency of sound – combine them in the proper order and you get a song. Manipulate them by changing the math. But it’s a little harder for us to really grasp the analog nature of speakers. It’s all about waves and variances and magnetism and vibrations. It’s the stuff that real scientists mucked around with 150 years ago, and they did it without computers or even electric lights. You just had a few guys like Elisha Gray and Alexander Graham Bell who were experimenting with the idea that you could convert sound into electricity and back. They didn’t know what they were doing, and they sure didn’t know how much they’d change the world.

About the Author

Stuart Sweet
Stuart Sweet is the editor-in-chief of The Solid Signal Blog and a "master plumber" at Signal Group, LLC. He is the author of over 8,000 articles and longform tutorials including many posted here. Reach him by clicking on "Contact the Editor" at the bottom of this page.