Before you're able to use Steam Voice Chat you'll need to configure your microphone within your Steam settings.
This can be done from the Steam client by clicking on the button labelled Steam
and then choosing Settings
from the drop down menu.
Mac users will need to choose Steam
and then Preferences
from the applications menu at the top of the screen.
From the Steam settings
page click on the Voice
tab at the top to access your microphone settings.
If you're using Steam Big Picture
these settings can be found by clicking the settings
button from the main screen and choosing voice
The microphone settings are split into three sections. The first of the three will allow you choose your recording (microphone) device. You can change which recording device Steam uses by clicking on the Change Device
If you've recently added a new microphone or removed an old one Steam can re-detect recording devices by clicking on the Detect Audio Devices
The next section allows you to adjust your send and receive volumes. The microphone volume will adjust how loud you are to other people, and the receive volume will adjust how loud other people transmit to you.
The last section allows you to choose if you'd like to use push-to-talk or sensitivity. Selecting Automatically transmit my voice whenever I speak
will enable sensitivity; in other words your microphone will transmit if it detects sound.
If you select Use a push-to-talk key to transmit my voice
you'll need to hold down your specified Push-to-talk key to transmit. You can change the Push-to-talk key once this option is checked.
When you're done configuring your settings click on Ok
to save them.