This guide walks you through how to play sound in your Lens. You can find info about how to import audio file and other types of Audio Tracks here.

Sound Best Practices

When preparing your sound resource for Lens Studio, keep the following optimization recommendations in mind:

• Use the MP3 format
• Use mono instead of stereo
• Use sounds that are < 15 seconds

Playing Sound

Sounds are added to a scene using an Audio component added to an object. Sounds are then played using a short playback script.

Your Lens can play multiple sounds simultaneously (e.g. looping background ambience paired with event based sound effects).

Import the Sound

To import your sound, drag and drop your audio file into the Resources panel.

Create Audio Component

To create an object with an Audio component. Press "+"  button at the Objects panel and select -> Audio.

Reference audio track by clicking on the Audio Track field and selecting your imported sound or dragging audio track onto the Audio Track field or the Audio component.

Audio Component UI

• Audio Track -  the Audio Track asset to play
• Autoplay Loop - if enabled sound will play and loop automatically. This is great for looping music or background ambience
• Volume - set the volume of audio 

• Mix to Snap - allows to record sound directly into the snap. In this case input from microphone will be ignored. Please note that in order for microphone audio to not be present on the final snap all Audio components should have this option
  • Record volume - the volume of audio recorded to the snap

Spatial Audio

Spatial audio is the technique that allows to process sounds in such way so they appear to come from their real location in space. Spatial audio requires AudioListener Component. 

• Distance Effect - allows to simulate sound attenuation which depends on distance to the audio listener
  • Curve Type  - describes how volume of the audio source changes with distance. See Audio.DistanceCurveType 
  • Min Distance - if distance is less than this value we do not apply distance effect at all
  • Max Distance - if distance is larger than this value we can not hear any sounds
• Directivity effect - applies directivity effect to the Audio component that simulates sound attenuation based on the orientation of the Audio component relatively to the Audio Listener
• Position Effect - applies effect to the Audio component that simulates the position of the sound by outputting different result to Left and Right channel. Best effect achieved in the head phones.

Playing Audio

To play sound any other way than Autoplay Loop we need to create a Script that will play the sound.

In the Resources panel, select + -> Script. With the newly added script selected, head to the Inspector panel to replace the text in your script resource with the following code:

// Play Audio
// @input Component.AudioComponent audio
script.audio.play( 1 );

Tip 
The play function takes in the number of times you want the sound to play as the input parameter. If you want the sound to play indefinitely, pass in -1 .

Connect the Script

We can now use this script to play the sound in the Audio component we created earlier.

With our object selected, add a Script component in the Inspector panel. Select + Add Component -> Script. Click the + Add Script field and select the script resource we just created. Set the script to run on the Lens Turned On event. Finally, bind the Audio field to the Audio component.

You can also use Behavior Script or Visual Scripting to play the audio.

Previewing the Sound

Press the refresh button in the Preview panel and you should be able to hear your sound.

Related Guides

Please refer to the guides below for additional information:

• Scripting Overview
• Audio Component