How Amazon Echo Works


Echo Hardware
The Amazon Echo got a tiny sidekick, the Dot, in March 2016.
The Amazon Echo got a tiny sidekick, the Dot, in March 2016.
Amazon.com Inc.

Amazon Echo is a cylindrical device that measures around 9.25 inches (23.5 centimeters) in height and 3.27 inches (8.3 centimeters) in diameter. A microphone off/on button and an action button at the top of the device provide some control options, and they rest on a ring you can rotate to adjust speaker volume. But the main control is the seven-microphone array built into the top, which uses beamforming technology and noise cancellation to "hear" your voice (i.e., record it and send it to the cloud).

A light ring at the top outer edge provides status information, such as the volume level and whether the device is streaming audio or the microphone is turned off, via various light colors and motions. An LED that lets you know the status of the device's WiFi connection sits near the base just above the power cord. Echo comes with a 21-watt power adapter, which is its only power source. Sorry — you can't carry it around with you.

The device incorporates two downward-firing internal speakers: a 2.5-inch (6.4-centimeter) woofer and a 2-inch (5-centimeter) tweeter. They take up roughly the lower half of the cylinder. They're covered in cloth, and speaker holes let the sound travel to your ears. A reflex port in the air chamber above the speakers reportedly decreases distortion and enhances the woofer's sound.

Teardowns have revealed that the device contains three circuit boards. A small board at the bottom contains Texas Instruments (TI) power and speaker drivers. A circular board at the top (integrated into the volume control wheel) houses components for the control buttons, volume wheel, status LEDs and microphones. A rectangular, side-mounted board above the speakers contains the brains and communication components, including the following [sources: Cunningham, Detwiler, Ifixit]:

  • TI DM3725 ARM Cortex-A8 Core Digital Media Processor
  • A TI power management integrated circuit (IC)
  • 4 gigabytes (GB) of NAND flash memory
  • 256 megabytes (MB) of LPDDR1 random access memory (RAM)
  • A Qualcomm Atheros QCA6234 dual-band 802.11n WiFi and Bluetooth 4.0 module.

But as you'll find out later in this article, the real brains behind the device rest in the cloud.

An optional remote control is sold separately. The remote includes a microphone, a talk button and a directional track pad (with play/pause, previous, next and volume symbols) for easy audio control.