Lost in music

“Whether we notice or not, immersive audio is the natural form of audio we humans experience,” as perfectly explained by the CEO and co-founder of Indy Audio Labs, Rick Santiago. Amy Wallington digs deeper into what is required to have real immersive audio at home.

One of the most commonly used buzzwords of late is ‘immersive’. Every speaker launched nowadays is described as being immersive, whether it is technically true or not. A truly immersive experience can only be achieved if sound is physically coming at you from all directions. “It may be a direct sound coming from a single source direct to your ears and/or an indirect sound reflected off walls,” says Tom Garrett, international sales manager at Trinnov Audio. “It may be a combination of multiple sources (think birds tweeting in trees) and single source (a plane flying overhead) with its sound reflecting off buildings.”

An immersive experience is achieved when the viewer/listener/gamer gets lost in the movie/music/game. The experience needs to envelope the person and be as lifelike as possible to ensure the speakers and screen become invisible.

Technology developments have now come so far that most people, regardless of budgets, can have some level of immersive audio in their homes, with the most affordable being a soundbar or upfiring speakers. Paul McCambridge, director of sales, EMEA at Xperi says: "You can get an elevated, immersive experience from as few as two speakers using DTS Virtual:X technology or seek out an immersive DTS:X soundbar featuring multiple speakers that reflect sound off the walls and ceiling to completely envelope you."

But some would say this is not a truly immersive experience. Roland Hoffmann, director of product marketing at Lyngdorf Audio and Steinway Lyngdorf, argues: “If we take the meaning of ‘immersive’ and the word ‘experience’ seriously, the answer is no, a soundbar cannot achieve this. Some clever soundbars can trick your brain a little, but the effect soon wears off and it sounds rather unreal. Our hearing ability to perceive sound three-dimensionally is much better than this.”

It can also depend on the room set up, as Garrett explains: “With virtual acoustic sources, such as soundbars or upfiring speakers, you rely heavily on the shape and acoustics of the room to give you nice and coherent ceiling and wall reflections compared to the sound coming from direct firing speakers. It is very difficult to predict the performance of such a system in any room and the user gets very little control over the end result. It will feel more enveloping, but there is an argument about the actual fidelity of such systems, which definitely lacks precision compared to physical acoustic sources. Besides, the experience will be very different from one seating position to another. But you could call this an affordable level of immersive audio.”

Island Prestige by L-Acoustics Creations is a 360° Immersive Hyperreal sound space for music, wellness, sound art and home entertainment. The elegant exterior conceals a concert-grade sound system composed of 18 monitors and two 18-inch subwoofers

Jumping out of the horizontal plane

Traditionally, home cinemas of the past had 2D surround systems at best, with speakers all around them. Predating surround sound was monaural sound and then stereo sound.

“Monaural sound is perceived as coming from one point in space (a single loudspeaker),” analyses Rick Santiago, CEO and co-founder of Indy Audio Labs. “Stereo sound is not only perceived as coming from two points in space (left and right loudspeakers) but also potentially from every point along a horizontal axis connecting the two stereo loudspeakers. Surround sound attempts to enable sound sources to come from all directions across a horizontal plane, not just between the left and right speakers. Immersive audio takes this technology a significant step further by reproducing sounds along a vertical direction above the listener, conceptually like a ‘dome’ of sound.”

Immersive audio adds a new dimension to the audio, allowing the experience to truly envelope the listener through height channels. Objects are able to move much better around the room between speakers to give a more lifelike performance. McCambridge adds: “A multichannel home entertainment system may be built around and above you. If the highest possible spatial resolution is desired, purchase a DTS:X Pro AV receiver or processor and enjoy immersive audio from up to 32 speakers.”

“Creative professionals are no longer constrained by discrete channels in the horizontal plane.”

Giles Martin, sound experience lead at Sonos points out: “With regards to the added value of surround sound, I should note that it is really hard – in fact, it goes against physics – to have direct sound behind you without having any speakers in place. As soon as surround or rear speakers are added to the setup, the listener is physically immersed in sound because audio is coming from all sides.”

As Olivier Thumerel, CEO of StormAudio explains: “Surround sound only uses a bed layer in the XY horizontal plane, whereas immersive audio adds another dimension, height channels in the z-axis, to be able to reproduce sound over the listener. The increased number of channels in both dimensions means more precision and sonic information can be reproduced, creating this immersion where the experience is close to real life.”

Premium immersive set ups in home cinemas and media rooms are the only way to enable sound to travel around the viewer and ‘immerse’ them in the content. “With discrete channels rendering, you create more points of diffusion for sound source signals, providing the accurate sensation of height and surround locations,” says Sébastien Gailleton, director of product management at StormAudio. “The more channels you add, the higher the spatial resolution becomes, providing a smooth reproduction transition from speaker to speaker when sound effects are panning all around you in the room. Of course, this depends on the room size. In a small home theatre space, a 7.1.4 set up can suffice, but it is often not enough when the room gets bigger, requiring 9.1.6 systems or even 11.1.8.”

A 9.2.6 speaker layout concept in a home cinema. Image: Xperi

Experiencing live

Taking this a step further, L-Acoustics focuses on bringing a live music experience to the home. “At L-Acoustics, our company history has evolved by making audio feel more real, initially within the context of live music,” says Dr. Christian Heil, L-Acoustics’ president and founder. “In 2016, we introduced ‘L-ISA Immersive Hyperreal Sound’ for both live and recorded media. It is immersive in the sense that it fully envelopes the listener.

“But being immersive is not enough from our perspective. The key for us is realism, or what we call ‘Hyperreal Sound’. Immersive Hyperreal Sound is audio so real that it feels like being there. In Immersive Hyperreal Sound, the listener must experience sound in its full spatial frequency and dynamic dimensions. This involves reproduction of sound with the same spatial accuracy and resolution as in nature.”

One consideration that needs to be thought through when building an immersive cinema or media room is the acoustics because it can have an adverse effect otherwise. “Multi-speaker solutions for immersive audio require multiple speakers being mounted around the room, not diverging too much from the prescribed ideal speaker locations,” explains Nilo Casimiro Ericsson, director of product management at Dirac. “It is usually challenging to make an ideal installation. With multiple speakers, the room acoustic interaction becomes more troublesome and really impacts the experience negatively, which is why most premium immersive home audio systems employ digital room correction.”

When we look at the high-end, it certainly pays to have an experienced custom installer who understands how the speakers should be laid out in order to create the most immersive experience possible. Gailleton explains: “There are two different technologies working together in most soundtracks. Most of the soundtracks are currently channel-based, meaning sound is recorded to be played on a specific speaker layout. With codecs such as Dolby Atmos and DTS:X Pro, object-based audio is added to the channel-based content. These objects are embedded in the mix as data information with its coordinates within a space, then this data can be decoded and rendered directly in the playback device depending on the number of speakers to calculate and place the position of the sound precisely relative to the size of the room and installation.”

Content creation

It’s not just the number of speakers and their placement in a room that affects immersive audio; content creators now have more ability to produce moving sound in more immersive ways.

“Immersive audio is the best way to experience your favourite entertainment, including legacy content,” says McCambridge. “Previously, home entertainment audio technologies placed sound from movies and games in pre-determined channels surrounding the listener, leading to less realistic representation. In life, sound is everywhere. Using immersive audio technologies, content creators may now place sounds where they would naturally occur in space, for a more true-to-life experience. Bringing cinema-quality sound into the home has never been easier. And with the entertainment landscape so dramatically different this past year than in the decades prior, there has never been a better time to elevate the audio in your home with immersive audio technologies like DTS:X.”

As immersive audio is becoming more widely known in the consumer world, adoption is also growing, giving creators more opportunities to produce creative content for people to enjoy.

“Together with sight, human perception of surroundings and experiences are affected and influenced by sound information received.”

Santiago adds: “To encode audio with this technology, new recording techniques have been required along with new storage and transport formats such as the more recent object-based audio formats from the likes of Dolby, DTS, and others. Audio playback systems become more complex requiring many more loudspeaker and amplifier channels than before. Room tuning technologies must be used to ensure that these more complex audio systems are working in a manner that doesn’t unnaturally favour certain frequencies or direction of sound arrival or distort the time relationship between sound generating loudspeakers.”

Besides speaker layouts and acoustic treatments, the development of audio production tools is what really creates an immersive experience, as McCambridge explains: “We typically think about immersive audio from the device side; these are the products that unlock immersive audio technologies in our homes, but it’s the evolution of audio production tools that have really given rise to these new listening experiences.

“Creative professionals are no longer constrained by discrete channels in the horizontal plane. They can now leverage three dimensions and audio objects to place a sound – or a symphony of sounds – with pin-point accuracy in the space around the listener. What we enjoy in our homes today is the result of content creators and their desire to deliver the most compelling experience that evokes that desired emotion in the listener.”

L-Acoustics Creations London showroom, open by appointment, features Ocean and Island 360° Immersive Hyperreal sound spaces

Competitive edge

A market that has gained a lot of traction over the last few years has been gaming and this is also a market that is driving audio development. But why is immersive audio so important in gaming?

“The gaming industry was an innovator in creating virtual worlds which use sound as potent clues to give a sense of space and engagement,” says Heil. “As humans, sound as produced in nature gives us a sense of the environment and helps us to make decisions. These properties are widely used in gaming to indicate the presence of other gamers or of imminent danger via sound effects or player footsteps in a spatialised environment through binaural audio.”

Transporting the gamer into the fictional world seems to be the ultimate goal of any game creator. To do this, the two main senses, sight and hearing, need to be addressed. “The senses that react first are the sight and hearing,” says Thumerel.

“Together with sight, human perception of surroundings and experiences are affected and influenced by sound information received. These senses are developed to be alert and the body responds to these sensory signals. In gaming, the immersivity and sense of being there in the scene can truly transport players into the world of games and heighten the involvement within the games. The audio cues add an additional layer to the interaction, and this can only be achieved with audio spatialised in 3D.”

The immersive experience is what puts the joy into gaming, enabling the gamer to escape to another world. “The gaming industry relies on a recreation of a world,” emphasises Martin. “The world we live in isn’t stereo so immersive audio can do a much better job of realising a recreated experience. If there’s a zombie behind you, then you should be able to hear that zombie behind you… and then run!”

L-Acoustics Creations offers end-to-end solutions for spatialised mixing and playback of Immersive Hyperreal Sound

Future

Although not a new development, the immersive audio trend is only just finding its feet. Consumers are now learning about it and hearing the differences between surround sound and truly immersive audio. Even with a lower level immersive set up, the difference is noticeable.

As Garrett says: “At the moment, immersive audio is probably the biggest and most exciting advancement in home entertainment. It’s a massive help that major heavy weights such as Amazon and Netflix are strongly supporting immersive sound technologies. This first occurred with movies and TV shows and it’s now happening with music. Then you have video games which is another extremely, if not even more, relevant application for immersive sound. The number of relevant applications keeps growing, which lets us think there is still plenty of room to grow until mass adoption is reached.”

“Immersive audio is the best way to experience your favourite entertainment, including legacy content.”

Hoffmann raises the point that it’s not all about how many speakers there are, it’s also important to concentrate on the quality of the AV equipment. “One thing is often overlooked. With the latest Dolby and DTS productions, the sound quality is better than ever before. In the early days, audio was heavily compressed in order to fit onto a DVD. Today’s quality of sound effects and especially music recorded in the studios is absolutely amazing, it takes months to get it right. So, it would be a shame to squeeze it through basic entry-level AV receivers and soundbars. The quality of every audio component inside an AV processor as well as the sound and build quality of the loudspeakers matters.”

Heil believes immersive audio will become more integrated as a system. “We think the next opportunity for immersive audio, and sound in general, lies in the convergence of home entertainment, technology integration, and architecture into a new way of thinking that we call ‘sound architecture’. Today, sound systems are most often designed with a specific purpose or even a single use in mind: home cinema, ceiling elements in the kitchen to listen to the radio, a soundbar for the television, a music room. Our vision for the future would be a deeper dialogue about a more comprehensive sonic ecosystem involving architects and AV specialists to make sound and acoustics an integral part of a combined living and entertainment space.

“The all-in-one sound space would become the multi-purpose entertainment, cultural, and wellness hub of the modern home, built into the design itself. This sound space would benefit from advanced Immersive Hyperreal Sound, but also from options to use sound to enhance the room’s feel with virtual acoustics, to DJ, perform and create with sound for those inclined to do so, or to enjoy sound art on its own or paired with visual digital creations.”

Keep an eye out on our website for more articles looking deeper into immersive audio.

Main image: Dirac