VR acoustic and exciting applications for virtual reality
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The fascinating world of virtual reality (VR) has not only revolutionized the visual aspects, but has also opened a new chapter in acoustic perception and simulation.
Virtual acoustics is a general term for the modeling of acoustical phenomena and systems with the aid of a computer. It is the computer-based simulation, modeling, and manipulation of sound fields to recreate the auditory experience of a specific environment, involving processing audio signals in real-time to account for sound propagation, reflections, diffraction, and absorption.
Virtual acoustic modeling, a synthesis of acoustic reality and virtual space, forms the backbone for immersive audiovisual experiences in virtual environments. Virtual acoustics is used to describe and analyze sound behavior in digital environments, allowing researchers and engineers to better understand and control how sound interacts within virtual spaces.
The acoustics of a space are defined by the properties of the bounding surfaces, as well as the source and receiver positioning, which are crucial in both real-time and precomputed auralization setups. Auralization is the process of rendering audible the sound field of a source in a space to simulate the binaural listening experience.
This innovative technology makes it possible to recreate acoustic scenarios and spatial soundscapes realistically by integrating sound source modeling, environmental characteristics, and listener perception into a comprehensive virtual acoustics system.
The Audio Engineering Society provides authoritative standards and research in the field of virtual acoustics, ensuring best practices and ongoing advancements.
Psychoacoustics research is vital in understanding how room acoustical phenomena are perceived. The incorporation of Virtual Reality in psychoacoustic experiments provides audio and visual cues to give the listener a better sense of space.
However, more research is needed to understand the problems hearing-impaired persons face in everyday listening situations.
This introduction highlights the importance of this topic and outlines the structure of this blog article to provide a comprehensive insight into the world of VR acoustics.
Applications of VR-acoustic model superstructures
I have personally had several projects in the automotive sector. Without giving too much away, the companies were interested in in-car auralization.
The automotive industry uses virtual acoustics to simulate cabin noise and sound quality during the design phase, allowing soundproofing tests without physical prototypes.
The idea is that sound propagates in the vehicle into virtual reality through measurements, specifically using measured Room Impulse Responses (RIRs) to ensure realistic simulation of in-car acoustics. This is a very useful application in product development and research.
The use of headphones as an aid is revolutionary in a variety of industries and offers projects a new definition to consider the sound image in planning.
Through this, requirements are created that help manufacturers improve the sound quality of their vehicles and acoustically optimize vehicle designs.
In some cases, experiments are conducted with participants to evaluate their perception of different acoustic environments within the virtual vehicle cabin.
Possible applications in mechanical engineering
The integration of a virtual sound field extends across various industries. Even though most people talk about spatial computing glasses, the focus is primarily on the ear. Here are a few examples from the media.
Audio in the field of architecture offers, among other things, the possibility of simulating the acoustic properties of virtual spaces. At present, acoustical performance in VR systems is often represented only by basic room parameters or simple descriptions, highlighting the need for more immersive auralization to improve design communication.
This enables architects and designers to analyze and improve the acoustic conditions and construction of buildings even before they are physically built.
This technology supports the creation of an optimally built environment that are focused on acoustic features in various spaces such as concert halls, auditoriums or living rooms.
In education, a virtual acoustics setup in VR offers an immersive learning environment. Teachers can visualize acoustic phenomena and allow students to experience them in a virtual environment, with playing of sounds processed to simulate real-world acoustics.
The user benefits from real-time updates of 3D acoustics based on their position and orientation, enhancing the learning experience.
This can help to improve absorption of the acoustic concept or phenomena, be it in physics, music or other branches of science.
In safety and emergency training, a virtual acoustics setup in VR can be used in sound simulation for realistic and immersive scenarios where acoustic responses to a warning signal are critical.
Playing sounds with accurate spatial cues allows users such as rescuers, firefighters and other emergency teams to train their communication and speech under realistic conditions.
Virtual acoustics create safe training scenarios with realistic audio feedback for emergency responders and surgeons. Learn more about VR training and sound.
The integration of virtual reality and acoustic technologies opens up a wide range of possibilities in the medical field.
Surgeons can train their skills with the help of acoustic feedback in realistic VR simulations. For patients, VR and acoustic elements offer opportunities to reduce anxiety and stress through direct sound, and to support pain management.
Virtual acoustics helps sound designers create immersive experiences, optimize sound in challenging environments, and reduce production costs. Learn how Medical Sound can accelerate the healing process with VR.
Technological basics of acoustic virtual reality
The principle of acoustic simulation in VR via headphones is based on the creation of an immersive audio experience that gives the receiver the feeling of being in a specific environment.
Virtual acoustics relies on digital signal processing (DSP) to simulate how sound travels from a source to a receiver, taking into account the position of both the source and the receiver within the virtual space.
The simulation is designed in such a way that it accurately reproduces natural auditory cues, including how sound arrives from different directions, and how the position of the receiver affects the perception of the acoustic environment.
These cues mimic real-world phenomena like diffraction, occlusion, and reflection. The effectiveness of these simulations is often limited by computational and methodological boundaries, which define the balance between accuracy and performance in virtual acoustics systems.
How can you make a measurement spatial using headphones?
Virtual acoustic space (VAS) is a technique that creates the illusion of sound originating from any desired direction in space when presented over headphones.
Hearing something through headphones in virtual reality is done using HRTF (Head-Related Transfer Function), a technology that takes into account the individual sound filters of the human ear.
The perception of an externalized sound source in VAS is due to the frequency and direction-dependent filtering of the pinna, which is part of the external ear structure.
These filters create a unique spectral pattern at the eardrum for each sound source location, allowing accurate localization and externalized perception.
These filters are used to modify sounds so that they can be heard at different positions in the listener’s head. Binaural microphones, such as dummy head microphones, are often used to capture spatial cues necessary for realistic 3D audio perception.
This process involves several stages: analyzing the direction of view in the scene, estimating transfer functions, and calculating how the realities would behave for the ears.
The sound fields come from all sides and reproduce the area around the listener in the best possible quality. VAS is also used in scientific research to study how the brain perceives sound source location, often involving subjects who respond to virtual auditory stimuli.
Software use and formats
Unity or Unreal Engine as a development platform forms the basis for visual representation and interaction in virtual reality. Wwise, on the other hand, as an audio engine, controls and processes the soundscape in this environment.
Virtual production tools enable immediate, real-time adjustments to acoustics during production, streamlining workflows.
Ambisonics, a technique developed for spatial sound recording and playback, enables the precise placement of sound sources in a 360-degree sound environment.
Techniques like Ambisonics allow sound to be positioned in a full 360-degree sphere, enhancing immersion in gaming and film. Loudspeaker arrays are often used in sound field synthesis and virtual acoustics to facilitate real-time auralization and spatial sound reproduction.
This format is actually only suitable for 360 videos (3 degrees of freedom), but is exciting for impulse responses and reverberation times and therefore also for 6 degrees of freedom.
Ray tracing achieves precise visualization and simulation of the environment in real time, allowing realistic experiences through both visual and acoustic aspects.
Hybrid modeling approaches, which use combined methodologies such as wave-based and geometrical models, are increasingly used to optimize both accuracy and computational efficiency in room acoustics prediction.
Hybrid modeling combines different methodologies to accurately predict room acoustics while managing computational demands for virtual reality applications.
However, this software solution is not yet as real-time as one would like. Apple wants to use it for its augmented reality glasses to create the space of the building.
Advantages of scenes for products
The integration of virtual or mixed reality into the world of acoustics offers a variety of benefits for companies and industries that rely on acoustic precision and spatial sound quality.
Presence in virtual acoustics enhances the user’s sense of being in VR/AR by creating spatialized soundscapes. Virtual Reality (VR) and Augmented Reality (AR) provide immersive, 3D audio that changes dynamically as the user moves, allowing for a more realistic and engaging experience.
Dynamic sound adaptation in virtual acoustics adjusts sound in real-time based on user movements and environmental changes, ensuring that users benefit from accurate and responsive audio environments.
Cost savings and increased efficiency: Virtual acoustics enable cost-effective design testing and early error detection, resulting in savings on subsequent physical adjustments.
The technology shortens development times (e.g. for acoustic rendering), increases efficiency in optimizing designs and minimizes potential costs for rework.
Quality improvement and resource optimization: By using VR acoustics, engineers and designers can improve sound quality and optimize the efficiency of spaces. A consultant with expertise can help optimize resources and identify the right tools and implementation processes.
Maximizing investment value and subject matter expertise: The support of a consultant maximizes the investment value in VR acoustics by helping companies take full advantage of the technology.
This leads to an improved understanding of the complexity of the technology and its integration into the company’s workflows.
Outlook: Room acoustics for virtual reality
The incorporation of acoustic simulation data into virtual reality opens up promising prospects for future acoustic design and planning. This approach, which has been under discussion for several years, is receiving increasing attention in the academic community.
Realistic spatial audio in virtual acoustics creates convincing 3D environments by modeling sound wave interactions with surfaces such as walls, which play a crucial role in shaping the acoustic environment.
The use of frameworks in game engines such as Unity and the Unreal Engine makes it possible to model acoustic phenomena such as sound absorption, reflection, diffraction and the Doppler effect in real time.
Rendering in virtual acoustics simulates how sound propagates in an environment, notably including early reflections and late reverberation, which are essential for immersive experiences. Modeling the scene involves defining the geometry, materials, and positions of sound sources and listeners in virtual acoustics to achieve accurate and realistic results.
The material properties on the objects in the development environment influence the calculation of the sound distribution in real time.
Air up for the tools
These technologies open up possibilities for a realistic and immersive acoustic experience. Virtual acoustics allows precise manipulation of room acoustic properties through the process of auralization.
Auralization involves the use of measured, synthesized, or simulated numerical data to generate virtual acoustic environments, with measured Room Impulse Responses (RIRs) providing highly accurate representations of how a room acts upon sound and affecting audio quality in virtual acoustics.
Real-time auralization extends the flexibility of the player object, independent of predefined measurement points.
Rapid iteration in virtual acoustics allows designers to test different material properties and analyze their impact on sound, while users can switch between different acoustic presets instantly in virtual environments.
Virtual systems in performance spaces can enhance sound in poorly acoustical rooms using microphones and speakers.
A human speech, a video or music feels more realistic, as if it occupies physical space. However, this application requires acoustic materials to be stored in the virtual room model in advance.
A future integration of real-time simulation into these virtual environments holds potential, but requires consideration of how the existing basic principles of Wwise and Unity can be maintained.
Possible optimizations and further developments could take into account the use of loudspeaker surround arrays.
Psychoacoustics do not build themselves
When creating VR and AR projects and developing innovative acoustic environments, it is crucial to have an experienced contact person. As an expert in this field, I am at your disposal to support your project with my extensive expertise.