Spatial Audio vs Surround Sound in Android: What’s the Difference
Both spatial audio and surround sound aim to create an immersive listening experience by making it seem like sounds are coming at you from different directions. However, the technologies work differently to achieve this goal.
Spatial audio, sometimes called 3D audio, uses advanced audio processing to make sounds seem like they are coming from all around you, even above and below. This creates a realistic 3D soundscape.
Surround sound, on the other hand, relies on having multiple speakers placed around the listener to envelop them in sound. While surround sound has been around for decades, spatial audio is a newer technology that doesn’t require a complicated multi-speaker setup.
In this article, we’ll take a deeper look at how spatial audio and surround sound work, key differences between the two, which devices support them, and how the user experience compares.
What is Spatial Audio?
Spatial audio refers to sound technologies that create a three-dimensional audio environment for listeners. It aims to replicate the experience of sound coming at you from all directions, as it would in real life. According to Dolby, spatial audio “uses advanced signal processing to enable a dramatic sense of space, depth, and dimension when listening through headphones or built-in speakers” (https://www.dolby.com/experience/home-entertainment/articles/what-is-spatial-audio/).
Spatial audio gives the illusion that sounds are occurring outside of your headphones. This creates an immersive listening experience that mimics how sounds would be perceived in the real world. For example, if a bird chirps in a spatial audio recording, it will sound like the bird is actually next to you rather than confined within the headphones (https://www.qualcomm.com/news/onq/2020/11/what-spatial-audio). This sets spatial audio apart from traditional stereo sound.
What is Surround Sound?
Surround sound refers to audio reproduction techniques that create an immersive listening experience by encompassing the listener with sound from multiple directions. The goal is to simulate being in the middle of the action, as if sounds are coming from all around the room. This creates a more natural and realistic listening experience compared to standard stereo audio from just left and right speakers.
Surround sound systems accomplish this effect by using multiple audio channels routed to different physical speakers placed around the listener. For example, a basic 5.1 surround system would have five main audio channels – left, center, right, left rear surround, and right rear surround. The “.1” refers to a sixth low-frequency effects (LFE) channel just for bass sounds like explosions.
There are several major surround sound technologies used in home theater systems, gaming, and entertainment. These include standards like Dolby Digital and DTS, which encode multi-channel audio into a digital signal. Newer formats like Dolby Atmos and DTS:X add height channels for overhead sound effects. The placement and number of speakers can range from 5.1 up to 7.1 or more.
Overall, surround sound aims to make audio more immersive by reproducing a 360-degree sound field. This provides a sense of space and directionality that stereo audio cannot match. The listener feels like they are inside the action, with sounds coming at them from all directions.
How Spatial Audio Works
Spatial audio is designed to create a more enveloping sound experience by simulating how sound naturally occurs all around us. It utilizes multiple audio channels fed to speakers that surround the listener to replicate a 360-degree sound field like in real life (https://www.dolby.com/experience/home-entertainment/articles/what-is-spatial-audio/).
The key technology that enables spatial audio is head-tracking. This allows the audio mix to adjust in real-time based on the position and orientation of the listener’s head. Headphones with built-in accelerometers and gyroscopes track head movements and relay this data to the audio processor. As the listener turns their head, the processor adapts the audio feeds to each earbud to match the soundscape to the new head position (https://www.trustedreviews.com/explainer/what-is-apple-spatial-audio-4143251).
For example, if a sound is meant to originate from the left side and the listener turns their head so their left ear is facing away, the audio feed to the right earbud will increase while the left earbud feed decreases. This creates a convincingly stable spatial sound field that immerses the listener and mimics natural hearing.
Advanced spatial audio technologies like Dolby Atmos also add elevation data to place sounds at varying heights all around the listener. This takes the immersion to the next level for a truly three-dimensional audio experience.
How Surround Sound Works
Surround sound systems work by sending specially encoded audio signals to multiple speakers located throughout the room, typically including front left, front right, center, surround left, surround right, and subwoofer channels. The audio is recorded with directional information using multiple microphones so sounds can be reproduced coming from specific directions when played back over the multi-speaker setup (1).
The audio data contains two audio streams – one destined for the front speakers and one for the rear. These streams are shifted out of phase from each other during encoding. A surround sound decoder receives both streams and shifts them back into phase relative to one another. This allows the surround audio signals to be separated and sent to the proper speakers, creating the illusion that sounds are coming from different directions around the listener (2).
Advanced surround sound formats like Dolby Atmos and DTS:X add height channels, allowing audio objects to be precisely placed and moved in three-dimensional space. The key to surround sound is having multiple speakers surrounding the listener, along with clever encoding/decoding, to deliver an immersive audio experience.
(1) https://www.performance-audio.com/blog/how-does-surround-sound-work/
(2) https://electronics.howstuffworks.com/surround-sound.htm
Key Differences
Spatial audio and surround sound both aim to create an immersive listening experience, but achieve it through different methods. Here are some of the key differences between the two technologies:
Surround sound uses multiple speakers placed around the listener to simulate sound coming from different directions. Spatial audio relies on head tracking and HRTFs (head-related transfer functions) to create a 3D soundscape that moves dynamically with the listener’s head movements (1).
Spatial audio is object-based, meaning sounds are tied to objects in the mix rather than speaker channels. This allows it to adapt the audio rendering based on the environment and device. Surround sound relies on speaker channels to direct sounds (2).
Spatial audio requires specialized hardware like accelerometers and gyroscopes to track head motion. Surround sound works with any properly arranged speakers. Spatial audio can simulate surround sound convincingly over stereo headphones while surround needs multiple speaker channels (1).
Spatial audio can present a fully spherical sound field around the listener. Most surround sound setups are limited to 5.1 or 7.1 horizontal channels. However, surround sound supports more speakers for greater precision in object placement (2).
In summary, spatial audio aims to recreate a 3D soundscape that moves realistically with the listener using head tracking and psychoacoustic processing. Surround sound directs sounds to fixed speaker positions around the room to immerse the listener (1).
(1) https://devialetchat.com/Thread-Surround-Sound-vs-Dolby-Atmos-vs-Spatial-Audio
(2) https://gizmodo.com/how-apples-spatial-audio-works-and-how-its-different-fr-1846108008
Supported Devices
Here are some Android devices that support spatial audio and surround sound:
- Google Pixel 4, 4 XL, 4a, 4a 5G, 5, 5a, 6, 6 Pro, 6a, 7, and 7 Pro support spatial audio when using compatible wired or wireless headphones, such as Pixel Buds Pro (according to https://developer.android.com/media/grow/spatial-audio).
- Samsung Galaxy S22, S22+, S22 Ultra, Z Fold3, Z Flip3, and newer models support Dolby Atmos spatial audio (according to https://www.samsung.com/us/support/answer/ANS00082941/).
- OnePlus 9, 9 Pro, 10, and 10 Pro support Dolby Atmos spatial audio (according to https://www.oneplus.com/product/oneplus-10-pro/specs).
- Sony Xperia 1 III, 1 IV, 5 III, Xperia Pro-I, and Xperia 10 IV support 360 Spatial Sound (according to https://www.sony.com/electronics/360-spatial-sound).
Many high-end Android phones from 2021 onwards support some form of spatial or surround sound audio when used with compatible content and accessories.
Supported Apps
There are a number of apps that support spatial audio and surround sound on Android devices. Here are some of the key apps with support:
- Netflix – Netflix supports 5.1 surround sound audio as well as Dolby Atmos on select content. This allows for a more immersive viewing experience with spatial audio effects on supported devices [1].
- Disney+ – Disney’s streaming app supports both 5.1 surround sound as well as Dolby Atmos spatial audio for a theater-like experience at home [2].
- Hulu – Hulu allows streaming select movies and shows in 5.1 surround sound when available. Hulu also supports Dolby Atmos on some content.
- YouTube – YouTube provides support for spatial audio and surround sound for playback on compatible devices. This includes 5.1, 7.1 and Dolby Atmos surround formats.
- Amazon Prime Video – Select titles on Prime Video are available with 5.1 surround sound as well as Dolby Atmos spatial audio.
User Experience
Spatial audio aims to create an immersive listening experience by making it seem like sounds are coming at you from all directions. This gives the listener a feeling of being surrounded by the audio instead of it just coming from stereo speakers in front. According to CNN Underscored, spatial audio can make content more engaging and captivating by adding dimensionality to the sound.
In contrast, traditional surround sound relies on having multiple speakers placed around the listener to create a surround effect. This can provide an immersive experience, but requires proper speaker setup and calibration. With surround sound, the sounds are anchored to specific speakers rather than seeming to move around you like spatial audio.
Overall, spatial audio offers a more flexible and adaptable surround experience, since it doesn’t rely on speaker placement. Users with headphones can enjoy surround effects from any location. However, surround sound may provide a more true-to-life experience when properly configured in a home theater setup. Both offer an immersive audio experience, just in different ways.
Conclusion
In summary, spatial audio and surround sound are two different audio technologies that aim to create an immersive listening experience. Spatial audio uses head tracking to make sounds appear to come from all directions, while surround sound relies on multiple speakers placed around the listener.
The key differences between the two are:
- Spatial audio only requires two earphones/speakers and head tracking, while surround sound needs multiple speakers placed strategically around the room.
- Spatial audio can deliver a personalized 3D soundscape using just headphones, but surround sound requires being in the center of the speaker setup to get the full effect.
- Spatial audio adjusts the audio in real-time based on head movements, whereas surround sound has a fixed sound field.
In the end, spatial audio aims to bring a surround sound type of experience to your mobile devices and headphones. While surround sound still provides an immersive experience at home or in theaters, spatial audio makes it possible to enjoy 3D audio on the go. Both technologies have their benefits and are continuing to improve over time.