[Update February 17, 2018: The kit was previously referred as ESP32 LyRaTD MS1, but the company appears to have changed the name to ESP32-LyRaTD-MSC]
So apparently voice command will represent 50% of all searches in the next two years, and everybody is jumping on the smart speaker bandwagon, with announcements from many companies at CES 2018, including Google’s Android Things + Assistant products‘ announcement, NXP i.MX 8M official launch, Amazon Alexa Voice Service (AVS) development kit from Amlogic and Allwinner, and more.
Espressif Systems is about to join the party with their ESP32 LyraTD MS1 HDK (Hardware development kit) that most people will likely remember as “Audio Mic HDK” that was announced on Twitter.
Espressif Audio Mic HDK specifications:
- Wireless Module – ESP32-WROVER module with 802.11 b/g/n WiFi and Bluetooth 4.1 LE connectivity.
- DSP – 4-mic array chip
- Storage – micro SD card for audio files
- Audio driver chip
- Earphone jack
- Dual speaker output ports
- 4x microphone array with up to 3 meter sensitivity while playing music
- I2C/SPI header
- 6-pin UART header
- I2S header
- Others undocumented
- Debugging – USB-UART micro USB interface (based on CP2102N), and JTAG header
- Misc – Power switch, 8x keys on top
- Power Supply – 5V via micro USB port
The kit can work over WiFi or Bluetooth, supports major cloud voice vendors such as Amazon Alexa, Google Assistant, and Baidu DuerOS. Soft decoder, and hot word recognition runs directly on ESP32 processor.
In twitter, the company also said you could implement your own hotword/keyword, by providing around 5000 unique recordings of your selected word, and that they expect to ship the board next week. It’s unclear when the board will be available for sale however.
One of the commenter mentioned he made his own ESP32 Circle evaluation kit with an audio jack, and a single microphone. If you are interested in that third party board, you can purchase it on Taobao for 169 RMB (~$26). The official Espressif Audio Mic HDK should sell for a bit higher due to the extra features.
[Update: Espressif ESP32-LyraTD-MSC is now sold for 44 Euros on Olimex]