AES Europe 2025

In today's era, 3D audio enables us to craft sounds akin to how composers have created sonic landscapes with orchestras for centuries. We achieve significantly higher spatial precision than conventional stereo thanks to advanced loudspeaker setups like 7.1.4 and 9.1.6. This means that sounds become sharper, more plastic, and thus plausible – like the transition from HD to 8K in the visual realm, yielding an image virtually indistinguishable from looking out of a window.

In the first part of his contribution, Lasse Nipkow introduces a specialized microphone technique that captures instruments in space as if the musicians were right in front of us. This forms the basis for capturing the unique timbres of the instruments while ensuring that the sounds remain as pure as possible for the mix.

In the second part of his contribution, Nipkow elucidates the parallels between classical orchestras and modern pop or singer-songwriter productions. He demonstrates how composers of yesteryear shaped their sounds for concert performances – like our studio practices today with double tracking. Using sound examples, he illustrates how sounds can establish an auditory connection between loudspeakers, thus creating a sound body distinct from individual instruments that stand out solitarily.

This tutorial proposal presents a comprehensive exploration of spatial audio recording methodologies applied to the unique challenges of documenting Eastern Orthodox liturgical music in monumental acoustic environments. Centered on a recent project at the Church of the Assumption of the Blessed Virgin Mary and St. Joseph in Warsaw, Poland, the session dissects the technical and artistic decisions behind capturing the Męski Zespół Muzyki Cerkiewnej (Male Ensemble of Orthodox Music) “Katapetasma.” The repertoire—spanning 16th-century monodic irmologions, Baroque-era folk chant collections, and contemporary compositions—demanded innovative approaches to balance clarity, spatial immersion, and the venue’s 5-second reverberation time.
Attendees will gain insight into hybrid microphone techniques tailored for immersive formats (Dolby Atmos, Ambisonics) and stereo reproduction. The discussion focuses on the strategic deployment of a Decca Tree core augmented by an AMBEO array, height channels, a Faulkner Pair for mid-depth detail, ambient side arrays, and spaced AB ambient pairs to capture the room’s decay. Particular emphasis is placed on reconciling close-miking strategies (essential for textual clarity in melismatic chants) with distant arrays that preserve the sacred space’s acoustic identity. The tutorial demonstrates how microphone placement—addressing both the choir’s position and the building’s 19th-century vaulted architecture—became critical in managing comb filtering and low-frequency buildup.
Practical workflow considerations include:
Real-time monitoring of spatial imaging through multiple microphone and loudspeaker configurations
Phase coherence management between spot microphones and room arrays
Post-production techniques for maintaining vocal intimacy within vast reverberant fields
Case studies compare results from the Decca/AMBEO hybrid approach against traditional spaced omni configurations, highlighting tradeoffs between localization precision and spatial envelopment. The session also addresses the psychoacoustic challenges of recording small choral ensembles in reverberant spaces, where transient articulation must coexist with diffuse sustain.

This presentation focusses on side and rear channels in recordings in Dolby Atmos. At present, there is no standardised placement for side or rear speakers. This can result in poor localisation in a major portion of the listening area. Sometimes, side speakers are at 90° off the centre axis, sometimes up to 110° off axis. Similarly, rear speakers can be anywhere 120°-135° degrees off axis; in cinemas those can be located directly behind the listener(s). However, an Atmos speaker bed assumes a fixed placement of these side and rear speakers, resulting in inconsistent imaging. Additionally, placing side and rear speakers further off-axis results in a larger gap between them and the front speakers.

These inconsistencies can be minimised by placing these objects at specific virtual locations, whilst avoiding the fixed speaker bed. This ensures a listening experience which represents better what the mix engineer intended. Additionally, reverb feeds can also be sent as objects, to create an illusion further depth. Finally, these additional objects can be fine-tuned for binaural rendering by use of Near/Mid/Far controls.

Mr. Bowles will demonstrate these techniques in an immersive playback session.

The field of audio production is always evolving. Now with immersive audio formats becoming more and more prominent, we should have a closer look at what possibilities come with it from a technical but most importantly from an artistic and musical standpoint.
In our Workshop, "Unlocking New Dimensions: Producing Music in Immersive Audio," we demonstrate how immersive audio formats can bring an artist's vision to life and how the storytelling in the music benefits from them.
In order to truly change the way people listen to music and provide an immersive experience, we must transform how we write and produce music, using immersive formats not just as a technical advancement but as a medium to create new art.
In this session, we will explore the entire production process, from recording to the final mix, and master with a focus on how one can create a dynamic and engaging listening experience with immersive formats like Dolby Atmos. We believe that immersive audio is more than just a technical upgrade—it's a new creative canvas. Our goal is to show how, by fully leveraging a format like Dolby Atmos, artists and producers can create soundscapes that envelop the listener and add new dimensions to the storytelling of music.

Philosophy

Artists often feel disconnected from the immersive production process. They rarely can give input on how their music is mixed in this format, leading to results that may not fully align with their artistic vision. At High Tide, we prioritize artist involvement, ensuring they are an integral part of the process. We believe that their input is crucial for creating an immersive experience that truly represents their vision. We will share insights and examples from our collaborations with artists like Amistat, an acoustic folk duo, and Tinush, an electronic music producer known for his attention to detail. These case studies will illustrate how our method fosters creativity and produces superior immersive audio experiences.

New workflows need new tools

A significant pain point in current immersive productions is the tendency to use only a few stems, which often limits the immersive potential. This often happens because the process of exporting individual tracks and preparing a mixing session can be time-consuming and labor-intensive. We will address these challenges in our presentation. We have developed innovative scripts and workflows that streamline this process, allowing us to work with all available tracks without the typical hassle. This approach not only enhances the quality of the final mix but also retains the intricate details and nuances of the original recordings.
Our workshop is designed to be interactive, with opportunities for attendees to ask questions throughout. We will provide real-world insights into our ProTools sessions, giving participants a detailed look at our Dolby Atmos mixing process. By walking through the entire workflow, from recording with Dolby Atmos in mind to the final mix, attendees will gain a comprehensive understanding of the steps involved and the benefits of this approach to create an engaging and immersive listening experience.

Immersive audio has become a significant trend in music recording, reproduction, and the audio and entertainment industries. This workshop will explore microphone techniques for immersive sound recording from theoretical, aesthetic, and musical perspectives.

Capturing a music performance and its acoustic features in a specific reverberant field, such as a concert hall, requires specialized microphone techniques for immersive sound. Various microphone techniques have already been proposed for immersive music recording. Achieving a natural timbre, appropriate musical balance, wide frequency range, low distortion, and high signal-to-noise ratio are essential in music recordings for capturing the music performance, including immersive sound recording. The acoustic features of the musical performances can be naturally reproduced by appropriately capturing direct and indirect sounds in the sound field.

The first topic of this workshop will cluster and review microphone techniques based on their fundamental roles. The panelists will also introduce their immersive sound music recording concept, demonstrate their microphone techniques, and provide sound demos.

Immersive audio can expand the adequate listening area if the microphone technique is designed with this goal. This is crucial for popularizing immersive sound reproduction among music lovers. Therefore, the second topic of this workshop will discuss microphone techniques from the perspective of the listening area during reproduction. The panelist will explain his hypothesis that lower correlation values in the vertical direction contribute to the expansion of the listening area.

In immersive sound recording, various microphone techniques have been proposed to reproduce the top layer of the multichannel discrete loudspeaker layout. It is recommended to use directional microphones and position the top and middle layer microphones simultaneously to avoid phase differences that can degrade timbre. However, some reports suggest that separating the top and middle layers can enhance the perception of vertical spaciousness. Experiments conducted by the panelists also suggest that separating these layers and lowering the correlation between them can widen the listening area without altering the central listening position's impression. Comparing microphone types and installation positions in the upper layer is challenging in actual recording situations. Therefore, the panelists will compare listening impressions under various conditions and allow participants to experience these differences using virtual recording techniques (V2MA), which will be discussed as the third topic of this workshop.

Several papers have reviewed microphone techniques, but most have relied on subjective evaluation. The third topic of this workshop will attempt to evaluate microphone techniques from a physical viewpoint. The panel will introduce the Virtual Microphone Array technique (V2MA) to determine how each microphone captures a room's reflection sounds and identify the acoustical features of several microphone arrays used for immersive sound recording. V2MA generates Spatial Room Impulse Responses (SRIR) using a virtual microphone placed in a virtual room with spatial properties of dominant reflections previously sampled in an actual room.

Lectures and demos help us understand the acoustical features and intentions behind microphone techniques, but they are insufficient to grasp their spatial characteristics, especially for immersive sound recording. The panelists will provide 7.0.4ch demos to showcase the spatial features of microphone techniques using V2MA. V2MA generates the acoustic response of a microphone placed virtually in a room, calculated from spatial information of virtual sound sources, such as dominant reflections detected from sound intensities measured in the target room. This workshop will illustrate the spatial characteristics of microphone arrays, allowing us to discuss the types of reflections captured by microphones and discover the differences in spatial features between microphone techniques.

Following each panelist's presentation, a panel discussion will delve into microphone techniques from theoretical, aesthetic, and musical viewpoints. This workshop aims to review issues with microphone techniques for immersive sound and discuss potential solutions to achieve natural spatial reproduction of musical performances for home entertainment.

Since we've moved from stereo to surround and 3D/immersive productions, many immersive music mixes still sound very much like larger stereo versions. Part of the reason for this is the record company's demands and the argument, that people don't have properly set up systems at home or only listen with headphones. But that's not the way to experience the real adventure, which is to create new, stunning sound and musical experiences. The workshop will not criticize mixes, but try to open the door to the new dimension of music and discuss the pros and cons that producers have to deal with today.

The evolution of 3D audio has significantly influenced the music and film industries, yet its full potential remains untapped. This panel will explore how immersive audio technologies, including Ambisonics, Dolby Atmos, and volumetric sound, shape new frontiers beyond traditional applications. We will focus on three key areas: accessibility in video games, the integration of 3D audio in gaming experiences, and its growing role in the automotive industry. Our panelists will discuss the state of the market, technological limitations, and emerging opportunities where spatial audio enhances user experience, safety, and engagement. This discussion aims to inspire innovation and collaboration among researchers, developers, and industry professionals.

The ECHO Project (Exploring the Cinematic Hemisphere for Orchestra) is a collaborative research initiative that explores 3D microphone array techniques for orchestral recording, involving eight experts in immersive sound recording: Kellogg Boynton, Anthony Caruso, Hyunkook Lee, Morten Lindberg, Simon Ratcliffe, Katarzyna Sochaczewska, Mark Willsher, and Nick Wollage. Building on the 3D-MARCo initiative, this project aims to provide a platform for sound engineers, composers, researchers, and students to experiment with various immersive recording techniques. To this end, an open-access database of high-quality orchestral recordings was created from a recording session at AIR Studios, London, featuring a Oscar-winning composer Volker Bertelmann and the London Contemporary Orchestra.

The ECHO database includes recordings of four pieces, captured using up to 143 microphone capsules per piece. This setup includes seven different microphone arrays designed by the experts, spot microphones, a dummy head, and a higher-order spherical microphone system. The database allows users to not only compare different techniques but also to experiment with mixing different microphones, helping them develop their own techniques. It also serves as a useful resource for research, teaching and learning in immersive audio.

This workshop will present the rationale behind each microphone array used in the project, detail the recording process, discuss the immersive approach to composition and recording methods, and present some of the recordings in 7.1.4.

*Introduction
With the growing market of immersive audio, both new and exciting production possibilities are emerging, alongside the resurfacing of existing surround sound production techniques. As audio production continues to evolve, understanding the impact of temporal properties on spatial perception becomes increasingly critical. One of the most effective ways to create a sense of space and depth, as well as to enhance listener envelopment, is through precise manipulation of temporal characteristics of sound.

*Temporal Adjustments in Audio Production
In stereophonic recording techniques, spatialization is often achieved by carefully controlling both each microphone’s distance from the sound source and the distance between microphones, in conjunction with leveraging variations in microphone sensitivity through polar patterns and directional rejection.
These distance-based variations introduce time delays, which are fundamental to spatial localization and depth perception. Similarly, in post-production workflows, delaying and applying differentiated effects to signals serve as powerful tools for enhancing immersion and spatiality. The controlled use of delay, reflections, and micro-temporal variations plays a significant role in shaping perceived auditory space. These techniques are widely used in both as mixing approaches with music and also sound design where artificially introducing delays helps simulate the propagation of sound in physical spaces, creating a more authentic and immersive auditory experience.

*Psychoacoustic Phenomena and Spatial Perception
Closely delayed or slightly altered signals give rise to psychoacoustic effects that influence spatial perception rather than purely temporal perception.
For instance, the number, spectral characteristics, and temporal distribution of reflections can lead a listener to perceive an auditory environment akin to a concert hall, even in the absence of an actual reverberant space.
The well-known Haas effect (precedence effect) provides insights into how human perception prioritizes the first-arriving sound over subsequent delayed versions, influencing localization and clarity. Additionally, the concepts of Temporal Integration Window (auditory signal fusion) describe how multiple signals originating from the same source are perceptually fused into a single event, affecting spatial coherence and envelopment.

*Workshop and Study Overview
This workshop presents and exemplifies findings from an ongoing semester-long study, which is currently being prepared as a submission to the Journal of the Audio Engineering Society. The study investigates whether sensation, timbral perception, and temporal integration windows are influenced when the delayed signal's spatial position is altered. By showcasing how spatial modifications of delayed signals affect auditory perception, the workshop aims to contribute insights to the field of immersive audio production.

*Conclusion
This research underscores the importance of temporal manipulation in immersive audio, bridging psychoacoustics with production techniques. By examining spatial perception through the lens of delay-based processing, the study offers new perspectives on designing more effective immersive sound experiences. The workshop will provide participants with theoretical insights and practical examples, encouraging further exploration of the intersection between temporal properties and spatial audio design.

In this session, we propose a path for the evolution of immersive audio technology towards accelerating commercial deployment and enabling rich user-end personalization, in any linear or interactive entertainment or business application. We review an example of perceptually based immersive audio creation platform, IRCAM Spat, which enables plausible aesthetically motivated immersive music creation and performance, with optional dependency on physical modeling of an acoustic environment. We advocate to alleviate ecosystem fragmentation by showing: (a) how a universal device-agnostic immersive audio rendering model can support the creation and distribution of both physics-driven interactive audio experiences and artistically motivated immersive audio content; (b) how object-based immersive linear audio content formats can be extended, via the notion of Acoustic Objects, to support end-user interaction, reverberant object substitution, or 6-DoF navigation.

In this workshop, we present the next generation of Immersive audio capture and reproduction through virtual acoustics. The aural room, whether real or generated, brings together the listener and the sound source in a way that fulfills both the listener’s perceptual needs—like increasing the impression of orientation, presence, and envelopment—and creates aesthetic experiences by elaborating on the timbre and phrasing of the music.
Members of the Immersive Audio Lab (IMLAB) at McGill University will discuss recent forays in creating and capturing aural spaces, using technology ranging from virtual acoustics to Higher Order Ambisonics (HOA) microphones. Descriptions of capture methods, including microphone techniques and experiments will be accompanied by 7.1.4 audio playback demos.
From our studio sessions, we will showcase updates to our Virtual Acoustics Technology (VAT) system, which uses active acoustics in conjunction with 15 omnidirectional and 32 bidirectional speakers to transport musicians into simulated environments. Workshop elements will include a new methodology for creating dynamically changing interactive environments for musicians and listeners, ways to create focus and “mix” sound sources within the virtual room, experimental capture techniques for active acoustic environments, and real-time electronics spatialization in the tracking room via the VAT system.
On location, lab members have been experimenting with hybridized HOA capture systems for large-scale musical scenes. We will showcase multi-point HOA recording techniques to best capture direct sound and room reverberance, and excerpts that compare HOA to traditional channel-based capture systems.