"you have to say the word "Alexa" for it to start listening"
That means that it is ALWAYS listening. It needs to listen for that trigger word at all times.
That means that it is ALWAYS listening. It needs to listen for that trigger word at all times.
Most of the time, it is not paying attention - the chip that is processing the sound is looking for the ONE word that will activate it. That passive audio processing is happening locally on a chip that is dedicated to the task. Once activated - the expensive processing happens and the sound gets processed, converted to text, sent to the cloud.