All you need to know about 8D Audio: An Introduction
Have you chanced upon a YouTube music video recently – one that left you wondering if there was someone playing sound directly behind you? Remember the virtual barber shop that did the rounds a few years ago?
If the answer to either of those questions is yes, then you have experienced 8D audio!
Heralded as the future of immersive audio by some and a flimsy gimmick by others, 8D audio is at the very least an interesting aural experience that deserves a second listen. Let’s take a glance at what it is, what it isn’t, and how it’s made.
What is 8D audio?
A new trend in online content and audio production, 8D audio describes a system of presenting music or audio to a digital audience. Commonly used in YouTube music videos to add an extra layer of interest to the experience, it makes the music sound as if it surrounds the listener, revolving around their head in different spaces.
8D sound mimics the effect of binaural audio, a sound format optimised for headphones that recreates the perception of distance to make audio more immersive. Binaural audio uses two microphones in a head shaped mounting to capture a realistic spatial soundstage.
Ambisonic audio is a similar type of specialised audio that captures several channels of directional audio to create highly immersive 3D recordings. All these types of spatial audio are used in VR experiences, video games, music videos, podcasts, and beyond.
Who invented 8D music?
It is unclear who invented the 8D concept, although the first binaural audio system, the “Théâtrophone”, was invented by Clément Ader way back in 1881. Adler designed the machine so people could listen to operas in stereo via their telephone lines, and laid the foundations for the technology to develop.
8D audio has become popular online in the last few years, with YouTube channels like Aviion Music and 8D Tunes posting 8D versions of popular songs since 2018. Well known hits from Ed Sheeran, David Guetta, and Daft Punk have all received the 8D treatment.
Some of the videos have well over 10 million views, demonstrating the attraction and clickbait power of 8D audio. It has become a popular tool for YouTube videos and streams, often accompanied with an audio visualiser animation.
What Does 8D Audio Mean?
Firstly, don’t be deceived by the name – there aren’t 8 dimensions of audio, as it might suggest!
Before diving in, let’s quickly look at audio dimensions. While opinions vary, there are three clear dimensions of sound perception:
- X: Width (left to right).
- Y: Height (floor to ceiling).
- Z: Depth (front to back).
Some have argued that Time and Loudness are two other dimensions of sound, although this debate extends into realms that are beyond the scope of what we’re discussing today.
In reality, the term “8D” is a fancy marketing name for a type of spatial audio effect. The argument for using a dimensional term to describe the effect falls apart upon closer inspection.
Due to the biology of the eardrum, sound will always have an element of “3D-ness” to it, partially thanks to the fact we exist in the three-dimensional plane of space.
People often confuse the number of spatial sources with the number of dimensions. For instance, some might think a mono track is one dimensional, though this is inaccurate, as due to our two channel hearing axis we will perceive it in 3D.
Is 8D audio real?
Technically 8D audio isn’t actually a real thing, if we take that to mean it doesn’t involve eight dimensions.
As mentioned, acoustic sound exists in a 3D space. So the reference to eight dimensions is more of a subjective description of how it feels, as if the sound is surrounding the listener. Imagine it as describing the eight corners of a cube – top left front, bottom right back, and so on.
8D audio is also created in sound editing software, so it’s more of an effect than a naturally occurring phenomenon. The 8D effect can be achieved with pan automation, or other 3D binaural and spatializer audio plugins.
What is the difference between 3D and 8D audio?
Because the terms are applied to audio without much technical grounding, 3D and 8D audio are both used quite interchangeably. The difference between them is hyperbole!
Multi-dimensional audio can include binaural audio and ambisonic recordings, which simulate realistic placement of sounds. The spinning spatial effect that we’ve discussed up until this point has been coined as 8D audio, but this type of sonic immersion is used in the same way in the gaming industry, and referred to as 3D audio.
This technology allows you to hear sounds as if they were happening around you. It puts the player right into the game, and brings added intensity to the gaming experience. A realistic sonic environment, where locating sounds is intuitive and natural, enables players to hear events around them and determine which direction they came from.
Think of an FPS where you are alerted to an enemy behind you with the sound of rustling grass, which your brain is tricked into thinking is actually happening in that location, due to the multi dimensional audio technology being employed.
How does 8D audio work?
The main process for creating 8D audio relies on the use of stereo panning and automation to give the impression that the sound is constantly revolving around the listener’s head.
The audio is programmed to repeatedly rotate in a 360 degree loop, so it takes time to move from the left to right speaker. Some 8D algorithms may use a Head Related Transfer Function (HRTF) to replicate the frequency filtering that occurs naturally when objects move around the head.
Additionally, reverb is added to 8D to give an extra layer of spatial perception. Carving out a different space for each part of the sound enhances the overall effect.
Can you listen to 8D audio without headphones?
While you can listen to 8D audio through monitors, the effect won’t be as noticeable or accurate.
8D and binaural audio relies on headphones because there is no crosstalk, meaning the sound from the left headphone only reaches the left ear, and not the right. With speakers, the sound propagates and reflects throughout the room, so the left ear will receive vibrations from the right speaker, and vice versa.
This interferes with the 8D (and binaural) processing, so some panning will be heard, but the full 360 degree soundstage is lost. For these reasons it’s best to use headphones when listening to 8D, and if you intend to release 8D videos you should make sure to mention this to your audience beforehand.
What does 8D music do to your brain?
The methods used by the brain to perceive sound’s spatial information are called interaural time difference (ITD) and interaural level difference (ILD). These are the psychoacoustic mechanics that our brains use to understand the directionality of sound, and are what is being played with by 8D and binaural audio.
ITD refers to the microscopic difference in time that sounds take to reach each ear. A sound on the left will take more time to reach the right ear, for instance. ILD concerns the level or “volume” of a sound; a sound on the right will be exerting more air pressure on the right eardrum than the left, so it is perceived as being louder.
Creators of 8D audio use this knowledge to create the spatialised sensation by manipulating the ITD and ILD of the audio source, which is decoded by our brain to create the perception of space and movement.
Is 8D audio harmful?
Currently there is no evidence to suggest that listening to 8D audio is more harmful or dangerous than listening to regular audio. The only risks at play are hearing damage from excessive volume, which is obviously a factor when listening to any type of sound.
That being said, people have reported feeling mild nausea or dizziness after listening to 8D.
Can 8D audio make you dizzy?
Some listeners experience slight dizziness from 8D audio, which is understandable as it simulates a kind of never-ending merry-go-round ride.
Listeners tend to complain more about nausea and dizziness if the 8D affect is applied at faster speeds, which can make the sound unbearably swirly, or if the effect is poorly mixed.
These are important factors to consider when making 8D videos.
How do you make an 8D sound?
For those wondering how to make 8D audio, don’t worry, there are a number of ways in which the effect can be achieved.
In an ideal situation, the original sounds would be recorded with a binaural microphone setup. If you are working with audio that hasn’t been recorded binaurally, the 8D audio effect could be achieved by automating the stereo pan of audio tracks, to give the impression of constant rotation. The automation would need to swap the left and right pan channels over time, and be enhanced using stereo widening techniques.
There are websites which can provide a quick fix, such as AudioAlter, where users can upload sounds to be 8D-ified. Using sites like these makes the process fairly simple:
- Choose the file
- Process the file with an 8D audio converter program
- Export, upload.
Examples of other spatialise software include:
- DearVR – a 3D audio plugin compatible with most DAWs
- Sound Particles – an immersive audio tool
- AudioCube – a standalone 3D audio program.
This is an emerging technology, and is being seen more and more in 360 degree videos such as The Journey to the Edge of Space, 3D Mega Coaster, and Exoplanet Tour. It’s not clear whether 8D audio will become widespread, but it is certainly popular, and offers something different to the listener.
Feeling sick yet? While 8D audio is an interesting and oddly popular audio effect, it’s a fairly stomach churning form of audio spatialisation. Getting the balance right in the sound design process is important, to avoid an overly unsettling experience.
Of course, looking after the listener is important in all types of audio processing, so make sure you’re getting the best out of your recordings with the ERA bundle. Our suite of audio repair plugins is the fastest clean-up solution for creators in any space!
