Holoplot’s Ground-Breaking X1 Matrix Array Sound System

We audiophiles often say that our interest in gear is rooted in our love of music. That isn’t always truly the case, but in this instance, it is. My interest in the German pro-audio company Holoplot came about because, a short while ago, I wanted to find out when Billie Eilish’s new album was coming out. I did a quick Google search, and one of the top results was a story from Spotify. The streaming service has partnered with Eilish to produce a series of immersive listening parties in London to celebrate the release of Hit Me Hard And Soft, which came out on May 17th. The listening events took place at the Lightroom digital art gallery in London’s King’s Cross. The high-tech venue uses Holoplot’s X1 Matrix Array system to fill the four-story cube-shaped space with sound. The system reportedly comprises an incredible 1,408 loudspeakers, along with 28 projectors. The audio tech is entirely hidden within wall cavities, so there’s nothing to visually distract from the 360-degree projection surface — a digital canvas of about 108 million pixels.

The Holoplot X1 Matrix Array Sound System

As soon as I read about Lightroom’s audio system, I had to learn more. The company behind it is Holoplot, a Berlin-based operation that has been around since 2011, “working on radically transforming audio technology by rethinking the underlying physics of sound reproduction,” according to the Holoplot website. The result of these endeavors is the X1 Matrix Array Sound System, a modular and uniquely flexible system described by its designers as “a groundbreaking product series that creates an entirely new category of sound system.” In a nutshell, the X1 system combines line arrays and electronic beam-steering technology and pushes both of these landmark innovations in audio to the extreme. The Matrix Array reportedly delivers “complete sound control in the horizontal and vertical axes,” and is ideal for multi-purpose event spaces, large-scale live entertainment venues, auditoriums, concert halls, and even theme-park attractions. The Holoplot Matrix Array promises to enable a new level of sound control via its proprietary technologies, which utilize a matrix arrangement of loudspeaker drivers of different sizes combined together in a unique multi-layered configuration. The speaker system is controlled by a powerful software application that “enables control over sound propagation across a large frequency range, while providing the SPL and quality desired for high-performance sound reproduction,” according to Holoplot. The system is said to be the result of a decade of pioneering research into Wave Field Synthesis and 3D audio beam-forming technology. The X1 gives the end user the ability to cover audiences precisely, even in large, acoustically-challenging environments, according to Holoplot. It can even avoid reverberant surfaces.

The X1 series includes two audio modules: the two-way MD96, with 96 drivers in a two-layered matrix design, and the three-way MD80-S, which has 80 drivers in its first two matrix layers, and a sensor-controlled subwoofer in its third layer. Each module has its own powerful DSP, which provides individual signal processing to each driver. Holoplot says that the system’s technological advancements in DSP algorithms combine with the high-performance sound reproduction capabilities of the drivers themselves to provide “a wide range of previously inaccessible sound control capabilities, from covering large audiences homogeneously to creating immersive audio landscapes.” Each driver is powered by its own individual amplification channel, and the amps are integrated into the modules so there’s no need to accommodate racks of external amplifiers. A Holoplot system can use any combination of MD96 and MD80-S modules deployed in any shape or size needed. The modules can connect in rows and columns, up to a virtually limitless scale, according to the company. A built-in rigging system allows the modules to be mounted to any surface or “flown” in free space for both permanent and temporary applications.

Holoplot X1: Under the Hood

The Holoplot OS is a Linux-based distributed audio operating system that runs on a dedicated dual-core ARM Cortex-A9. A high-performance FPGA (Field Programmable Gate Array) is used to compute the proprietary DSP algorithms for 3D audio beam-forming and Wave Field Synthesis, providing individual control to each driver. The result is “full sound field control for multiple beams in both horizontal and vertical directions,” according to Holoplot. The company says that each module provides more than 200 input channels fed with either object-based or channel-based audio streams. Then the routing matrix running on the FPGA down-mixes the 200-channel signal into 12 beams. Each individually-controlled beam can be equalized using a 24-band parametric EQ. Holoplot says that the system can “maintain every detail of the mix, uncompromised by distance, angle, or room acoustics…  making every seat the best seat.” The system reportedly allows the user to create “precise coverage and avoidance zones” in order to direct and shape sound while avoiding unnecessary reflections. Not only does this approach promise extremely even coverage, it also guarantees minimal loss in level over distance, according to the company. When deployed as a stereo L/R configuration, the 3D audio beam-forming promises a widened soundstage with sounds that are not perceived as coming from the source closest to the listener. Essentially, the sweet-spot as we know it ceases to exist. Instead, the mix is “equally distributed across the entire audience area, widening the sweet-spot and giving everyone a premium seat experience.”

Holoplot in Action: The Sphere

Beacon Theater Holoplot System

If any of this is sounding familiar, it might be because Holoplot’s technology is used inside the Sphere arena in Las Vegas, which has garnered a huge amount of press since even before the venue opened on September 29, 2023, with U2 as its first act. The band’s residency at the Sphere is called “U2:UV Achtung Baby Live at Sphere.” The Sphere is owned by Sphere Entertainment Company, which until last year was part of Madison Square Garden Entertainment Corp. Sphere Entertainment first invested in Holoplot GmbH in 2018 to develop the “Sphere Immersive Sound” system. Sphere Entertainment recently announced that it has acquired Holoplot in its entirely. The first members of the public to hear Holoplot’s Sphere Immersive Sound system weren’t actually in the Sphere. A version of the same system was introduced in 2022 at the Beacon Theatre in New York, which is operated by Madison Square Garden Entertainment Corp.

You can pinpoint a location, point at it, and send audio with such a degree of technical excellence that you can hit a spot 500 feet away. I was, like, oh my God, this is the future of our industry.

 — Joe O’Herlihy, Front of House Engineer for U2

Holoplot X1 Matrix Array: Flexibility and Invisibility

One unique and potentially game-changing feature of the Holoplot system is that it is configured digitally, eliminating the need to physically reconfigure the rig when the venue is being used for different types of shows, from rock concerts and cinema screenings to awards shows and keynote presentations. (I recently took my nephews to see the 1989 Batman movie at the Dolby Theater in Hollywood, where the film was being screened with a live orchestra playing the score. It quickly became painfully clear that the venue’s audio system, which probably works great for the Academy Awards ceremony held there each year, was not up to the task of providing sound reinforcement for the musicians on stage while also delivering intelligible dialogue.) Holoplot’s software can reportedly optimize the system to “address any show configuration.”

Another benefit of the X1 Matrix Array sound system is that it can be completely hidden from view, which is perfect for venues where visible audio equipment is undesirable — think London’s Lightroom art gallery, or Misr Masjid, a newly-built (and truly beautiful) Grande Mosque in Egypt’s new capital outside of Cairo. The mosque is one of the largest in the world, and its architects required a sound system capable of delivering clear speech to a huge congregation in a space of over 100,000 square feet. And this needed to be accomplished without compromising the architectural integrity of the building’s interior, which is composed mainly of highly-reflective marble. The architects were told that a conventional sound system would require loudspeakers to be installed in more than 30 locations in order to serve all 12,000 worshippers that the cavernous facility can accommodate. Instead, a fully-concealed Holoplot X1 Matrix Array system was used. Thanks to its beam-forming technology, the system achieves sufficient coverage and intelligibility from just nine positions, all without sticking out like a sore thumb against the backdrop of the building’s beautiful interior.

This grand mosque is an exemplar of X1's technological capability. We introduced several brand new system concepts that are not attainable with any other technology. The X1 Matrix Arrays utilize advanced optimization algorithms to generate uniform coverage in tightly defined zones with minimal spill to dedicated quieter areas or reverberant surfaces. This way, speech transmission and the direct-to-reverberant ratio were increased to record values. A steerable-line-array-based solution would have required the deployment of far more arrays to achieve anything comparable.

— Emad El-Saghir, Holoplot Engineer

I’m pleased to say that together with Holoplot, we met the client’s brief of creating a fully integrated system that satisfies all stakeholders. The project was full of challenges, starting from the size of the mosque, the room acoustics, and of course project deadlines. Thanks to X1’s ability to not only control sound in the vertical but also horizontal, it achieves unbelievable intelligibility, thought impossible in a space clad in marble and featuring a huge dome at its center. Holoplot exceeded our expectations in both the quality of sound, and in hiding the equipment in such a way that it blends in seamlessly with the interior.

— Emad Shenouda, Projects Director at Integrator Audio Technology

A “Quantum Leap” in Audio

Holoplot calls its approach to audio reproduction “science-based, software-driven, and hardware-enabled,” resulting in “a quantum leap in audio capability.” The company’s Matrix Array system certainly appears to be on the cutting edge, promising to make previously inaccessible capabilities available in the real world — even if that real world is currently limited to large and extremely well-funded projects. When going through the company’s online literature, one non-technical blurb caught my attention. Holoplot says that “when people experience better sound, they will enjoy more meaningful moments and create richer memories.” As an audiophile, I can get behind that sentiment 100%.

More information: Holoplot

Do you think this will be a quantum leap in audio that will revolutionize how we listen to live music? Please comment in the related forum thread below.