MIC+ installation guide

INSTALLATION

For Raspian users (level-> easy, duration-> 5mn):

-Insert your Rapsberry Pi Shield in your Raspberry pI then turn it on

-Open a terminal (yes the black window thing) and type this to download the bash file and run it:

sudo wget -O - mic.raspiaudio.com | sudo bash

-Say yes for the reboot

-On the next reboot you have to run the test to finish the installation (it is an ALSA oddness):

sudo wget -O - test.raspiaudio.com | sudo bash

Push the onboard button, you should hear “Front Left” “front Right” then the recorded sequence by the microphone.

It should sound like this:

If the volume is too low you can adjust the gain of the microphone by typing:

alsamixer

A gain at 50 is a good start:

cap.png

For desktop vlume control under Raspbian:

First enable the audio control, you need to go on the desktop-preference-Audio Device settings then click on “Select Control” and check both “Master” an “Micro”, then if you want to change the volume from your desktop you need to make a right click on the bluespeake iconr to open Audi Device Setting and adjust the sliders. let me know if it helps,

Here is the script source for the test

.For references here is the script source updated for Raspbian Buster.

For Volumio:

We recently added Rapsiaudio in the dac selection, you will find it in the last version of Volumio!

Just select “Raspiaudio” in dac selection and it should work straight out of the box :sunglasses:

For UBUNTU :

1- Edit the file /boot/firmware/config.txt

 >>sudo nano /boot/firmware/config.txt

 comment the following line (add a #):

 (ligne 22) : dtparam=audio=on

 by this one:

            : #dtparam=audio=on
            : dtoverlay=googlevoicehat-soundcard

2- copy the directory “overlays”
form /lib/firmware/4.15.0-1034-raspi2/device-tree
to /boot/firmware

 >>sudo cp -r /lib/firmware/4.15.0-1034-raspi2/device-tree/overlays /boot/firmware

3- reboot

For the official Google AIY image:

-Downlowad the official Google AIY image here

-Write the image to an SD card using a card writing utility (Etcher.io is a popular tool for this)

-Insert your Rapsberry Pi Audio Shield in your Raspberry pI then turn it on

-Open a terminal (yes the black windows thing) and type:

sudo wget -O - aiy.raspiaudio.com | bash

-run the audio test “Check audio” on your desktop, reboot to allow volume control on the desktop

-Follow this guide to setup the credential to run Google’s examples here

For the references the script souce is here

For the Alexa voice assistant:

-Install a fresh version of RASPBIAN STRETCH WITH DESKTOP and follow the setup explain in the first section above “For raspbian user”

-Then follow this good instructable until the end

-You now have to setup the sound output type to edit:

sudo nano /etc/opt/AlexaPi/config.yaml 

be sure that you have the following: sound section:

sound:
  # Name of your microphone device: "raspberrypi"
  # leave empty for default
  input_device: ""

  playback_handler: "vlc"

  # you can go here with alsa, pulse or others
  # keep blank for the best audio output selected by the underlying code
  output: "alsa"
  # output device: "raspberrypi"
  # currently supports ALSA only
  output_device: ""

  # if left empty, won't be passed to the underlying library / command if it su$
  # if it doesn't 100% will be used
  default_volume: 80

  # Means the same as above, but is used for media (playing music for example)
  # Leave blank to use the same setting as for speech content
  media_output:
  media_output_device:
  media_default_volume:

  # Some device: "raspberrypi"
  # value is the number of seconds of silence to pad the beginning and end of t$
  # the sox handler supports this configuration option.
  playback_padding: 0

Also change the GPIO setting for the trigger button and led:

  raspberrypi:
    # GPIO Pin with button connected
    button: 23
    # GPIO Pin for the playback/activity light
    plb_light: 25
    # GPIO Pin for the recording light
    rec_light: 25

Then reboot, if you push on the button you can ask an important question to Alexa:

How to break appart the microphone:

Moving the microphone further away form the speaker could be in some case usefull, for example if you would like to make a vocal assistant.

Use a cutter to weaken the part shown of the picture, give at least 10 pass of the blade above the little holes, then use your finger to apply pressure, try not to push too strongly of the microphone component (metalic rectangle). Then connect the cable as shown on the picture below.

View fullsizeWhatsApp Image 2018-05-05 at 18.36.24 (1).jpeg

View fullsizeWhatsApp Image 2018-05-05 at 18.36.24.jpeg

View fullsizeWhatsApp Image 2018-05-05 at 18.36.23 (1).jpeg

View fullsizeWhatsApp Image 2018-05-05 at 18.36.23.jpeg

How to turn off the speakers:

If your project requires to turn off the onboard speakers, note that on the Back of the board you have 2 soldering point CUTL and CUTR, using a soldering iron remove the 2 solodering point. This operation is reversible by adding back some soldering.

Pinout:

Please find the pinout on our friends at pinout.xyz:

Hello,

I have an RC522 module, and it already uses GPIO 25, is it possible to replace this GPIO by another?

Hi Aurel,
Indeed Pin 25 is used by the led :

It may not interfears wih your RC522 module, but if it does you will still be able to removed the led with a soldering iron or go brute force and cut/ destroy the led with a cutter.

Hope it helps!

Olivier for the Raspiaudio team

I finished the installation and then did the test. The test worked fine, as shown in the video.

But now my raspi shows ‘No volume control on this device’ on the audio icon at the top right corner. And I dont see any audio preferences.

Any advice on how to resolve this issue would be greatly appreciated!

Edit: One more issue I wanted to add to this - The test gives an ‘Overrun’ error several times. And the microphone recording is too noisy. Is there a way to resolve these issues too?

How do you control the microphone and speaker to -

  1. Record a stream of audio from the microphone.
  2. Process this stream of audio on the Rpi
  3. Output a stream of audio from the speakers, based on the processing done in step 2.

Thanks

For desktop vlume control under Raspbian:

First enable the audio control, you need to go on the desktop-preference-Audio Device settings then click on “Select Control” and check both “Master” an “Micro”, then if you want to change the volume from your desktop you need to make a right click on the bluespeake iconr to open Audi Device Setting and adjust the sliders. let me know if it helps,

this is a generic Alsa sound device, if you google “raspberry arecord” you will find plenty of examples
for example you can try:
arecord -d4 --rate=44000 test.wav

then play it:
aplay test.wav

if you prefer a software with graphic interface I recommend Audacity

thx!

Hello,

Is it possible to use Mic + with Node-red? If yes, how?

I have not tried it but you should be able to use the work from HifiBerry that is using the same I2S driver than us:
https://www.hifiberry.com/docs/projects/automating-your-hifiberry-with-node-red/