# Device Selection

### Demo details

This is a variant of the Echo Test demo: everything is exactly the same in term of available controls, features, and the like, with the substantial difference that you can select which of the available devices (microphones, webcams) you want to use for the media setup.

The demo will start by automatically selecting some default devices, pretty much as the regular Echo Test demo already does. Once done, you'll be able to individually change the capture audio and/or video device: this will result in the Echo Test channel being reset and recreated, in order to use the device(s) you selected instead. Just as with the regular Echo Test demo, the `?simulcast=true` query string will allow you to test simulcasting as well.

The demo exploits a functionality made available in the `janus.js` library, meaning you should be able to easily adapt all the other demos to follow the same approach as well, and that you'll be able to do the same in your Janus-based web application too.

Press the `Start` button above to launch the demo.

Audio device (input):
Video device (input):
Change devices

### Local Stream

### Remote Stream