When Australian electronic trio Rüfüs Du Sol made history as the first dance act to ever headline the prestigious Rose Bowl Stadium on August 16, 2025, they brought more than just their signature emotive soundscapes to Pasadena. Behind the unforgettable sonic experience that captivated 60,000 fans was a massive L-Acoustics sound system that demonstrated why the French manufacturer remains the gold standard for large-scale outdoor events.

We had a chance to speak to FOH Engineer Johnny Keirle about how he was able to provide stadium-surrounding sound for Rüfüs Du Sol for their recent stadium tour finale in Pasadena, CA.

What were the biggest acoustical challenges the Rose Bowl presented, and how did you address them with the L-Acoustics system design?

The biggest challenges were not the Rose Bowl itself, but the standards set by the artist and management to provide an unparalleled EDM experience at a large scale. We wanted to deliver an experience that can be challenging at small scales, let alone on a scale of this size: essentially aiming to turn a 60,000 person venue into a club.

Walk me through your decision-making process for the main PA configuration – why 16 K1s and 4 K2s per side rather than other combinations?

The main arrays comprised 4 x K1SB, 16 x K1 and 4 x K2, with 12 x K1SB flown behind. This combination was chosen based off SPL and contour requirements. The K1SB were  included for two reasons: to offer a different flavour of low frequency energy to complement the flown KS28 on the side hangs and ground KS28 sub array, as well as offer better directivity control of low frequency energy from the main system.

As much consideration was put into vertical low-frequency directivity as anything else, contributing to the choice to run longer line lengths than typically necessary for shows of this scale.

The subwoofer deployment was massive – 88 total units. How did you balance ground-mounted vs. flown subs, and what was the reasoning behind the KS28/K1-SB mix?

We had five primary subwoofer sources at the main stage: two hangs of 12 x K1SB (main hangs), two hangs of 12 x KS28 (side hangs) and a ground sub array of 36 x KS28 in 19 cardiod positions of 2 x KS28 each. Each delay tower had 04 x KS28 in an end-fire config of two positions of 2 x KS28 cardiod stacks.  

A lot of time was spent modelling system performance to maximise positive interaction, minimise negative interactions and assess where and how energy needed to be focused. We rely heavily on the ground sub deployment, particularly to create a “club” feel on the floor, while the flown elements are deployed to interact intentionally with their respective full-range sources ( both main and side hangs comprised 04 x K1SB / 16 x K1 / 04 x K2) to control directivity both in the horizontal and vertical domains.

The K1SB behind the main hang was chosen to maximise phase coherency with the main K1: offering better control of throw directivity, and in turn better control of the interactions between the flown LF resources and ground LF resouces.

Having the mix of K1SB and KS28 also allowed us to tailor the feel of the system’s sub response: for me, the K1SB being more percussive and transient-focused (excellent with the percussive sub elements of the show – live drums, pads, transient-heavy synths), with the KS28 offering the leg-shaking low end and richness in sustained sub transients and underlying sub content.

How did you determine the delay tower positioning and coverage patterns for a venue this size?

The positioning of delay towers was actually decided prior to my involvement, although I had an opportunity to make some changes if and as required.

I typically determine delay tower placements based off performances of the main stage system: having a pre-determined SPL target, and considering targeted system contour and LF extension into this allows me to use Soundvision to determine where delay reinforcement needs to begin. Lateral positions and azimuths of  delay positions are typically determined by considering arrival times between the main stage source(s) and delay source(s), with a huge focus on maintaining transient clarity and intelligibility: I’ll use various prediction tools to determine not only delay tower placement but also the most suitable source type for delays (in this case L2 / KS28), required delay SPL and contour capabilities, panflex settings, etc.

As an initial consideration I will look at HF / transient arrival consistencies with differing delay positions, followed by low-frequency interactions/contributions, and finally imagery across the full coverage zones of the delays.

What was your approach to system tuning across such a large venue with varying acoustical zones?

The majority of the system optimization is considered in advance: before I make noise with the system I’ve already made pre-determined contour EQ adjustments, calculated delay values, etc.

When dealing with a system of this scale, I’ll look primarily at optimising each source independently, wherever that source has exclusive coverage, and typically relying on design optimisation and pre-determined design decisions to predict how multiple sources will interact with each other.

The first step of my on-site workflow is ensuring all sources are deployed in their correct positions (checking rigging plots, measuring exact delay position placements, etc), so I can be confident in advanced optimisation choices made in the design phase.

How did you handle the delay timing between the main PA, outfills, and delay towers?

All delay timing is pre-determined in Soundvision and other proprietary calculators. With propagation time differences between sources being highly-considered in the design phase, when on-site I expect to have a good idea of how sources will interact and align from a delay perspective.

I do not measure delay times on site – I prefer to do this by ear.

Can you walk me through your process for integrating all the different fill systems (front fill, 270 fill, center fill) into a cohesive whole?

As with time alignment, all smaller fill systems are tweaked and tuned by ear. Main reasoning being that most fill systems (front fills / centre fill, etc) are influenced by on-stage sound. Integrating these by ear gives me more control over imagery and feel of the fill systems.

Centre fill and front fills in particular often differ drastically in terms of EQ and overall response: I’ll be looking for a system response and SPL that is suited to that one area of the venue: the pit. A few things I’m looking to achieve with these systems: match the energy of the sub array, create a suitable experience for people on the dance floor, and match the energy of the group on stage (including any acoustic contributions). I’ll always listen to the full system before the band gets on stage, but prefer to do all my front fill optimisation and adjustments with the band soundchecking or rehearsing.

With Rufus Du Sol’s heavy low-end content, how did you manage the sub arrays to avoid mud while maintaining impact?

All sub sources were deployed in cardiod configurations to manage directivity, and careful consideration was given to placement. Subwoofer sources deployed and interacting with full-range sources were positioned carefully to manage said interaction, with the same applying to positioning of multiple full range/sub sources.

What challenges did the open-air environment present for maintaining consistent frequency response across the venue?

Several factors to consider here, the most obvious being exposure to elements.

In any environment we are dealing with atmospherics affecting propagation, but outdoors we are going to be dealing with greater changes in conditions. We can usually expect drastically different atmospherics between an afternoon soundcheck and an evening show. I don’t remember the specifics from the Rose Bowl show.

Wind exposure is always a consideration outdoors, especially in an exposed environment like the Rose Bowl, and this was considered in the design phase.

I monitor changes  in temperature and humidity throughout the course of the day, making adjustments to compensate for differences in HF propagation. That said, we can’t as well predict or manage differences in temperature gradients, or the effect that a 60,000 person crowd has.

How does designing a system for electronic music differ from rock or pop shows, especially at this scale?

Live EDM has different frequency response requirements, as well as different sub and low transients. Live EDM is unforgiving, and with audiences used to “club” environments, standards are set that are harder and harder to achieve as show scales increase.  

Rufus Du Sol’s music has very dynamic arrangements – how did you ensure the system could handle both intimate moments and massive drops?

This is one of the main reasons we are using K1 as much as possible: the full range and high-output offers enough headroom for full transient reproduction, even for low frequencies at high SPL. Cam’s mix (FOH engineer) is very consistent, and very well-controlled. Knowing his output, I can be confident dimensioning a system in the design phase.

What considerations did you make for preserving the stereo imaging and spatial effects that are crucial to their sound?

This is considered in source placement and alignment: preserving a sense of spatiality is important, but that spatiality is unachievable if sources aren’t standardised, optimised and aligned correctly. Source positioning is the biggest part of this: in the design phase I want to make sure sources are positioned so that alignment and spatialisation is as consistent across the audience as possible.

What was the timeline for getting this massive system deployed and tuned?

We have a production day before a stadium show: everything is deployed and calibrated during this day. In the case of the Rose Bowl, the band did a full run-through in the evening of the production day, meaning we have to be up and running by the evening.

For this show, I actually flew in from Australia landing 7:00am the morning of the production day, and went straight to site to load in.

In detail.. My first moves on site are to take verification measurements to validate design drawings: confirming my room drawings are accurate, and that stage and delay towers are built as expected. Small position changes can make a big difference. With this project, I had to draw the venue in advance – so venue dimensions needed to be verified / corrected.

As part of this verification process, I also check trim heights are achievable and confirm hoists are rigged as per the rigging plots.

Once the system is deployed, we verify system functionality. I’ll look at coverage verifications, then begin system alignment and optimisation.

For RDS I target a very different system contour to usual; I don’t listen to any of my tuning tracks through the PA.. Instead, I used the live show to tune: either Cam (FOH engineer) will play virtual soundcheck through the system, or if unavailable, I have a stereo LR of the show.

Come show day, I’ll use the soundcheck window to continue listening and adjusting around the venue, and will do the same during the support band.

How many crew members were involved, and what was the most challenging aspect of the physical installation?

For this tour, we were travelling with a total of five people in the PA team: three PA techs from Unreal Systems, Marc-Olivier Germain as crew chief, and myself as SE. For the few stadium shows, we had additional crew join: an additional three PA techs from Unreal, as well as Luca Sabatini (Unreal account handler / owner), who was instrumental in making sure the additional crew, gear and logistics were under control.

On top of the PA team, we have the two engineers, each with a respective tech, and an additional tech in monitor world to help with gear adds and RF brought in specifically for the Rose Bowl show.

Audio crew:
Cam Trewin – FOH engineer
Gabe Santana – FOH tech
Jimmy Gueness – Monitor engineer
Benny Masterton – Monitor / RF tech

Touring PA team:
Marc-Olivier Germain – Audio crew chief and PA tech
Joe Williams – Unreal crew chief and PA tech
Juan Villa – PA tech
Mark Molton – PA tech
Johnny Keirle – System Engineer

Additional PA team for stadium shows:
Luca Sabatini – Unreal Systems

How did you coordinate with FOH engineer Cameron Trewin during the tuning process?

I do all my system measurements and optimisation independently, then Cam and I listen to the system together. Cam typically walks venue with me, and will be alongside me as I’m making adjustments. If there is anything he hears, he’ll mention it and we’ll address it together.

What tools did you use for system monitoring during the show?

I’m using Network Manager for ongoing optimisation throughout the course of the show, and for monitoring of system performance. I don’t run any RTA or TF monitoring during the show, and prefer to make show adjustments by ear.

Were there any moments during the performance where you had to make real-time adjustments?

I’m making regular small adjustments. Either to compensate for atmospheric changes, or changes in the feel of the show. With RDS I tend to make song-by-song changes to low-end filters.

How did you handle backup systems and redundancy for a show of this magnitude?

The whole system runs on AVB Milan: so, a self-managed in-built redundancy as part of the transport protocol already. As an additional fallback, we have AES hitting each amplified controller and configured to take over automatically if AVB sync is lost.

For front-end, I have two P1 processors in my drive rack. Each processor takes AVB from the FOH control, as well as analogue as a backup. As standard, AVB Milan is distributed from the Main P1, and the AES backup to the amplified controllers is fed from the Backup P1. If the Main P1 was to fail, the amplified controllers automatically fall back to AES from the Backup P1. I have Milan Manager configuration files to change AVB patch between processors in the event of a catastrophic processor failure

What’s your background that prepared you for handling a project of this scale?

I’m pretty familiar to designing projects of this scale: I’ve toured extensively on stadium tours with a number of artists, and am involved in a various large-scale annual projects that give me time each year to fine-tune my stadium design approach.

How has stadium-scale system design evolved during your career?

The tools available for offline, computer-based design optimisation have improved drastically. Improvements to tools like Soundvision and M1 within Network Manager have revolutionised how I approach system design and optimisation, particularly at larger scales.

Compared to 15 years ago, we can spend more time finessing in the design phase, and less time measuring and analysing performances on-site.

What advice would you give to aspiring systems engineers looking to work on large-scale productions?

Read and learn as much as possible, and don’t be afraid to experiment.

A good understanding the science behind sound system design is essential, and opens the door to experimentation. Hypothetical and design-phase experimentation has been a huge part of developing the techniques I now rely on.

I strongly discourage a “one-size-fits-all” approach to system engineering. Earlier this year, at L Acoustics’ L-Connect conference in Paris, I spoke about what I call “Adaptive Engineering” — the concept that every show or production should demands unique approach. There is no universal template; every system design should be tailored to the specific needs and targets of each project.

Another piece of advice: don’t underestimate the value of pre-production. With the design tools and prediction software we have access to today, we can achieve 90% of the system work offline. Advance and pre-production steps are as important as the “traditional” on-site steps. The advance is where we deep-dive, finesse desifns, and prevent avoidable issues on-site.

L-Acoustics Technology:

What specific features of the K1/K2 system made it the right choice for this application?

A number of things make K1 the right box for this application:

Full range frequency output and high SPL support a system design that can fully reproduce the dynamic content of live EDM, where smaller or less powerful formats would fall short. K1 allows us to manipulate coverage characteristics to lower frequencies, offering better control over flown LF propagation, and most importantly better control over interaction between the flown sub and ground sub sources. Extending the line source by adding K1-SB above the K1 main hangs further improves this low-frequency control.
Without the full-range headroom of the K1/K2 combo, we couldn’t maintain a linear relationship between the full-range and sub components of the system, resulting in dynamically inconsistent interactions. A well-dimensioned K1/K2 system offers linear and predictable interactions.

Another point – the HF. The density and coherency of the K1 HF waveguide allows for long-throw which is less susceptible to wind interferences, and the physical properties of a long line of K1 offer stability and prevent an exposed system from swinging around in gusts of wind.

How has the AVB networking and P1 processor integration changed your workflow compared to analog systems?

AVB is a very clever but user-friendly protocol. Easy to implement and monitor, and robust with inherent redundancy. The P1 as a front-end makes AVB integration simple, and again offers redundancy that make it suitable for live applications.

Any upcoming L-Acoustics technology you’re excited to implement on future projects?

The performance of the L-Series has been very impressive. I used L2 a lot in 2024 with Adele, and again in 2025 with Rüfüs Du Sol. I recently changed a Benson Boone arena tour design from K1/K2 to a full L2 system with excellent results — I’m looking forward seeing what other applications will benefit from these newer technologies and R&D.

How did the actual show performance match your expectations from the design phase?

I’ve become confident with design performance parameters and how these translate to real-world performance. That said, it’s always amazing to hear some of these larger-scale systems in real life: walking during the support act, in the furthest listening areas at the top of the bowl, had the impact, immediacy, imagery and low-end of the mix was more what you would expect listening <100’ from the stage – not >500’ from the stage.

What feedback did you receive from the band and FOH engineer about the system performance?

I didn’t have many conversations after the show – it was fairly late by the time load out was done (and I was flying back to Australia the following day) – but everyone was very happy. Tyrone (singer) made a point to say how many people had said how good it sounded around the venue, and Cam (FOH) had received similar feedback. Management are hands-on with this, and only had good things to say.

If you were to do this setup again, what would you change or optimize?

We made some last-minute changes to the design which introduced some rigging challenges – for example, I was unable to fly my delay subs and had to position them on the ground.

As far as the general design is concerned, I don’t know if there was anything I would change. Everything went about as well as it could have.

What does it mean to be part of the first electronic dance act since Depeche Mode to headline the Rose Bowl?

A fact I didn’t actually know. Nice to know we did something unique, and hopefully set a high standard for electronic acts going through the Rose Bowl moving forward.

How does this deployment compare to other major stadium shows you’ve worked on?

No two productions are going to have the same targets. That said, my approach for RDS is drastically different to a “typical” stadium design approach. The main differences between this deployment and my “typical” approach are all around low frequency: primarily the sub count and configuration. Typically, I’ll rely more on flown subs and less on ground subs. This conversation was had early on: Cam and the band want to have the feeling of ground plane coupling, turning a stadium floor into a club. Ground sub arrays come with unique properties; to achieve this feel for the floor while also providing suitable sub energy travelling distance (and to the sides of the venue) meant experimenting with and trying different design and alignment approaches to usual.

As part of this, the design of the full-range sources was also approached differently: making sure we had the resources for full-frequency transient reproduction at high SPL, and the line length to best manage flown low-frequency directivity and interactivity with the increased ground sub systems.

Another consideration that came as a byproduct of the above: managing low-end outside of the audience areas. Not only for the band on stage but also to minimise low-order reflections muddying up the audience areas, the designs put high emphasis on pattern control and cardiod configurations, deliberately steering areas of alignment as well as misalignment.

We thank Johnny for his time with this in-depth interview and a behind-the-scenes look at running sound for a massive dance music stadium show at the Rose Bowl! Additional thanks to L-Acoustics for arranging access to the show for EDM Life.  

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By: Greg Wasik
Title: Rüfüs du Sol tour Sound Engineer Johnny Keirle talks Stadium-Surrounding Sound and L-Acoustics Speakers
Sourced From: edmlife.com/rufus-du-sol-tour-sound-engineer-johnny-keirle-talks-stadium-surrounding-sound-and-l-acoustics-speakers/
Published Date: Fri, 24 Oct 2025 19:22:03 +0000

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