When all you need is a little soothing rain, Rain sound has you covered. The extension sits near your address bar as a little cloud. When you select the cloud you have two levels of sound: mild rain or rain with a little more thunder. It’s a constant loop from Rainy Cafe, but it downloads to your Chromebook. That lets it work offline. Simple and effective.
Although this extension runs offline, you’ll need to open it one time while online. Once you open online, it downloads the sounds for you. After that initial online setup, all the sounds work offline.
The extension has about 30 different sounds. They range from outdoor sounds like different birds and insects to musical instruments like drums or guitars. You can mix and match your sounds. Relaxing Sounds lets you play up to five at once. I wish it let you create different sound groupings like other apps. It doesn’t include a timer. The sounds play until you pause them.
Noise Shield Extension
Although it’s not listed as working offline, it works fine in my experience. Like Relaxing sounds, you’ll need to open it once while online. That downloads the small sound loops. The sounds include nature like Park River or Autumn Winds as well as the classic white, pink and brown noises. These sounds help drown out external noises or just help you to relax. Noise Sheild Extension also lets you start the noises with a custom shortcut. I like the timer function so when the sounds stop, you can switch to another task.
Although you can’t directly play videos offline with a Chromebook, YouTube has some great background music. You can extract the audio loops and save them to the Chromebook’s internal storage. Similarly, you can download those videos using desktop software or a Chrome extension like Backtick. I usually search for relaxation or focus. Some of my favorite sounds to work to are those of starships like The Enterprise or Battlestar Galactica.
I love Ambiance for iOS and Android. That app doesn’t work offline on a Chromebook, but that doesn’t mean you can’t get the sounds from the source. Freesound.org has a huge library of background noises designed to help you relax. The best tags to search for are ambient and soundscape. You’ll need to download them in advance, but you can keep them on an SD card. With VLC now supported on a Chromebook, that’s the ideal player for these type of files. VLC lets you repeat the sounds files on a custom playlist.