We’re talking of course about the carbon microphone amplifier, a piece of telephone technology which made its way into consumer electronics. The carbon microphone is a container of loosely ...

The micro speaker for wireless earbuds delivers clear sound without an amplifier, uses less power, lowers cost, and fits ...

While the style may vary, all hearing aids have the same basic parts: a microphone, amplifier, speaker, and battery. Here’s how they work: First, the microphone picks up sounds from the environment.