ALSA tools

included in many distros , included in LXM

ALSA : Advanced Linux Sound Architecture
framework for sound card drivers.

arecord is a command-line sound recorder
It supports several file formats and multiple soundcards with multiple devices. It is basically used to record audio using the command-line interface. 
Syntax:
`arecord [flags] [filename] ``
flags see : https://www.geeksforgeeks.org/arecord-command-in-linux-with-examples/

breakrecording with ctrl + C

test micro

it can be used to test microphone:

arecord -vv -fdat foo.wav

or

arecord -vv -f dat /dev/null

or

arecord -vvv -f dat /dev/null

create an alias or a shell function:

test-micro() {
    arecord -vvv -f dat /dev/null
}