PureAudio™ Speech Development Kit for Raspberry Pi

Raspberry Pi Microphone & Voice Recognition

PureAudio™: The Ultimate Raspberry Pi Microphone

When it comes to your IoT devices, Andrea’s got the powerful “ears” that can hear you, even in extremely noisy environments. That’s why we are used in millions of computers, police cruisers, robots, virtual teller machines (VTMs), customer service kiosks, intercom systems, and fast food restaurant drive thru order posts.

Our patented digital beam forming and adaptive noise cancellation signal processing enables accurate far-field speech recognition from up to 14 feet away, for a superlative performance in voice-operated IoT applications that require advanced audio input technology, including speech recognition microphones and noise reduction software.

What you get in the Speech Development Kit:

  • A stereo array microphone
  • A high fidelity USB external digital sound card providing stereo input and output 3.5mm jacks
  • A free download of the Beam forming noise reduction filter software along with the voice trigger phrase “Hello Blue Genie” that enables your Raspberry Pi to be controlled by far field voice commands. Note: This software only runs on the Andrea PureAudio USB sound card.

The audio software simplifies adding clean audio to any application on the Raspberry Pi.

This is achieved by providing two components:
The first component is an audio filter library, which provides the following functionality:

  • Handles capturing the microphone input from the USB device.
  • Handles sending the audio to be played out the USB device.
  • Filters the input audio with beam forming, noise reduction and acoustic echo cancellation to provide clean audio in noisy environments.
  • Provides trigger word and command detection, including barge-in when audio is playing out the speakers.
  • Optionally, provides the filtered input audio buffers to the main application.

The second component is a sample application that demonstrates how to use the simple interface to the audio filter library. This application listens for the trigger while playing audio out the speakers. When the trigger is detected, the volume of the audio playing out the speakers is reduced, and it makes a short WAV audio recording.

Raspberry Pi Microphone & Voice Recognition

For developers looking to enable the Raspberry Pi for voice recognition, a high-performance microphone and advanced noise-canceling software are vital for optimal performance and successful trigger-phrase detection.

A common problem with trigger-phrase detection is being able to detect the trigger-phrase when music is playing out of the speaker, located near the microphone. This is known as barging-in to the music in order to speak commands to the device.

The data below documents how Andrea’s audio filters significantly improve the barge-in performance of any speech recognition device, making the PureAudio™ Development Kit the ideal Raspberry Pi microphone.

The following graphs show the percent of successful commands from 2 feet (0.6 meters), 6 feet (1.8 meters), 10 feet (3.0 meters), 14 feet (4.3 meters) and 18 feet (5.5 meters).


Compare the performance of Andrea’s audio filters on the Raspberry Pi vs the Amazon Echo in far-field operation.

Click on the Software Images Below for Algorithm Details:

For superior voice recognition, count on the Andrea PureAudio™ Development Kit to create a Raspberry Pi microphone experience that significantly outperforms the rest!

Get PureAudio™ for Raspberry Pi