Written by Alyssa Barnhill

It's never a one man show, even if there is just one person in the spotlight. From the front of house to your ribcage, from the bass weight to the record crate, Hacienda Audio provides an all-encompassing workhorse through professional audio engineering and studio design. Outside of the studio, their master engineer Matt Davis recently unveiled his latest rig deployment for the home-grown Reference Sessions series in Denver, Colorado. Featuring an enormous and meticulously designed sound system, expansive LED walls, and precision front of house engineering, he and his cohorts are aiming to set a new bar standard for high fidelity concerts and events.

Sound system hardware and music production software have evolved parallel to one another, which in turn plays into the dynamic evolution of traditional and modern conceptions of “sound system music”. One of the many contemporary brains at the center of this phenomenon is Davis himself. His own roster of projects reaches far beyond just our musical niche, and that experience in concert with his rigorously academic application of engineering fundamentals is precisely what sets him apart from his peers. Consequently, those same skills are what should also set Reference Sessions apart from the competition. I had the opportunity to sit down and reference the master himself after their recent Reference Sessions 002 deployment in Denver for an intimate conversation about the philosophy and engineering behind one of the latest developments in the live audio playing field.

Alyssa Barnhill: What technology or equipment was used to achieve such an articulate and immersive sound experience at the event tonight, especially balancing the heavy bass weight with clear and crisp highs?

Matt Davis: For this event I really wanted to create an impactful evolution on existing tech that could be perceived and appreciated, not only by the connoisseurs and audiophiles of the room, but even to lay people coming directly from another event, with who knows how much hearing fatigue. For this reason I used a multi-pronged approach to improving sound quality through a few different mechanisms.

The first was by using a full digital signal path the entire way from the CDJs to the amplifiers, which did not contain the insertion losses which are present in your usual signal path in DJ based events. The usual exchange goes from digital in the CDJ back to analog in the DJ mixer output to the FOH path, and then to digital in the FOH console’s A/D converters and back to analog leaving FOH, before being converted back into digital by the amps’ DSPs and then back to analog for amplification. In our configuration the entire chain stays not only digital, but is also synchronously locked to the DJM’s clock for the most direct, coherent signal possible, much like is found in mastering rooms.

We also brought a LOT more headroom/wattage in the sound system than is typical of a 400 capacity room, which carried with it a lot of benefits both in the latitude of tonal expression possible in the sound system, and lower distortion figures, which allow me to run the subs hotter than in normal rigs without the incorporated harmonic distortion which extends into the upper bass/low mids masks detail. By using subs with a ton of headroom I find you can still yield a balanced sounding tone, but with much more bass weight than you’d usually be able to get away with due to the lower distortion, making the sound not only detailed and accurate, but very involving and at times extremely aggressive with subrange pressure.

There is a concept in acoustics known as “cabin effect” which occurs in small air spaces with very large amounts of SPL (sound pressure level) in them. Cabin effect is essentially the state where the entire air volume is fully pressurized and dynamic compression takes place not due to electrical/displacement shortages, but simply by the air molecules being unable to propagate any further. I’ve been familiar with this effect since high school due to my interest in car audio design for bass competitions, and it’s been a long term goal to bring enough displacement, wattage, and xMax to a venue to create that effect on a much larger scale than in a car. There were moments during Murkury’s bass bath and at other points in the weekend where I felt that we were near the threshold of that cabin effect sensation, I’ll never forget feeling my whole body tingle in a way I’ve never experienced for at least 10 minutes after the bass bath, I attribute this to powerful infrasonic extension and the subrange SPL we were able to attain even at FOH towards the back of the room for those three minutes during the bass bath.

Reference Sessions · Reference Sessions 002: Murkury & Lavier // Denver // 11/29/24

It could be argued that we have also improved upon the low end punch of a standard rig by trisecting the kick drum into three separate boxes (Kick First Harmonic Bin, TSW-718 (65-200hz), Kick Fundamental Bin, HSD Sherman (30-65hz), and Rumble/Infra Bin, V-Plated Battle Axes (15-30hz)) which separates and independently generates the different partials of the kick drum in a perfectly phase aligned manner, courtesy of our very talented alignment tech Brady Chionbian. Most rigs are 3-way or 4-way and use one box for the entire subrange or maybe a sub reproducing the fundamental and a kick bin to handle the first harmonic of the kick. In our 6-way configuration each partial of the kick drum is generated by a dedicated box which is inherently better protected from intermodulation distortion than a shared bin reproducing the full kick signal.

Another component of the secret sauce is the way that I perform FOH duties. I find most FOH engineers for DJ events have a tendency to either “respect the master of the music” by not altering it, or simply have a hands off approach to conducting FOH once they’ve established a starting level and tone. I, as a mastering engineer, don’t really care much for maintaining other peoples’ masters as they are when they don’t translate to the sound systems they are being played on, and take a very active role in improving the translation of those masters, mostly via dynamic EQ settings made on a song by song basis for each set of the night.

I vet the acoustic qualities of every room that I rent for an event by hearing, measuring, and messing with a sound system in the space in advance of renting it, and I personally vet every box of every sound system that we bring out for these events. I spend a lot of my time roaming around the country listening to what people say are the best rigs in the country, and I bring hybridizations of the ones I like best out for my events. For this event, we used most of Trash Fence’s inventory of Floodlights/718s and all of their subwoofers, and added four of Unify Mountain Soundz’ Battle Axes to round out the deployment.

We also design and fabricate new sound system technology to get closer to my metric goals of low frequency extension and lower distortion figures. We brought out the world’s first HSD Battle Axe V-Plate array at this last event which moved the low frequency cutoff of each 4-pack of axes from 26hz down to 18hz. I was shooting for 15hz, but I know how to get that low if not lower with my design for the next event’s sound system. I want the infrasonic range to be flat to single digits within the next few parties.

Lastly, we acoustically treat every venue that we use for a Reference Sessions party with materials donated by Hacienda Acoustics. A sound system will only ever be as good as the room you put it in, it doesn’t matter how talented of a deployment engineer and alignment tech you are, if the room sucks the sound will suck. I’ve been patiently waiting for years for the standards of acoustics/sound reinforcement in the US to get better, and somewhere along the line I got tired of waiting, so now we leave a wake of acoustically treated performance spaces to slowly and incrementally improve the standards of live playback in the US after every event, one venue at a time.

Alyssa: How was the sound system materially designed to create such a physical experience?

Davis: I attribute it to two things. Infrasonic extension which provides a more tactile/visceral/physical response when combined with strong subrange, and micro-dynamic control of transients in the program material by myself in FOH. There is a tendency in bass music to mix the snares and hats very loud with very little dynamic control, and this will tend to get very harsh through live sound speakers, even quite good ones due to their horn loaded nature and compression drivers. By controlling the energy/sound stage position of the snare and hats you keep them from jumping as far in front of the rest of the mix and becoming grating/fatiguing to the patrons while also revealing detail in the mix which was previously being obscured by the snare/hats.

Alyssa: What exactly are the “Reference Sessions”?

Davis: I basically wanted to create a series of parties that could be a “thank you” to my mastering/acoustics clients by paying them well to perform with a lot of amenities, a love letter to sound system culture, and a means for myself, my organizations, and my very talented friends to show off at a high level. We pride ourselves on very big productions in intimate and unconventional spaces, with excellent sound quality.

Alyssa: What techniques did you use to work with this specific venue?

Davis: I liked this particular venue because it had a classic dirty warehouse vibe, roughly the right size that I thought we could comfortably fill up with guests and that we could afford to acoustically treat, and the non-parallel ceiling with fiberglass lining. I tend to pick venues with fiberglass either attached to the ceiling or suspended above a drop ceiling. They usually sound considerably better than a flat and/or purely reflective ceiling. The main room had a moderate footprint with a lossy partial wall on one side which I knew would not present as a boundary for low frequencies and would allow the subrange to propagate through the entire footprint of the warehouse, allowing for deeper subrange extension. I also noticed a pretty strong constructive 25hz antinode in the room during analysis that I figured would support/enhance the deep sub/infrasonic range, and it very much did that.

Alyssa: What kind of challenges were in the way of achieving such a professional experience in a warehouse space like this?

Davis: Climate control was a big one, as the warehouse had no HVAC and the weather was pretty inclement at the time in Denver. We relied heavily on propane torches for heat during load in/alignment but we obviously couldn’t use them once doors open to guests. Electronics can be sensitive to temperature swings so navigating the logistics of keeping the place warm enough to keep the gear happy was a bit of a challenge.

Another big challenge was that we simply kept shaking our tech to death with subrange during stress testing of the sound system, and during the actual events. We killed one Armonia router a day for three nights straight, which was problematic seeing as how it provided our system engineer with amp health diagnostics during the event. These diagnostics are critical when you aren’t applying a highpass to your subwoofers as infrasonic energy can become incredibly destructive to subwoofer drivers if not properly tailored on a song by song basis, so I was essentially flying blind and relying on my ears to hear and correct for the drivers bottoming out in their unloading range in order to keep the subwoofers safe. We also killed an unused amp input on one of the Powersofts after stress testing the system, not via abuse but simply as a result of the incredible SPL taking place in “amp world” (which was between the front/rear sub arrays).

Alyssa: What steps were taken to balance the immersive visual elements, such as lasers and LED walls, with the impressive spread of sound?

Davis: I started planning this party hell bent on doing a temporary full visual immersive room using LED walls. We slowly had to pair that down to the realm of sanity and practicability for this event, though I intend to make it happen at a future party once we’ve built up a better internal supply of LED wall/trussing. What we wound up with was roughly 48x9’ of continuous LED which extended from behind the stage, around the speaker stacks, and into the sidewalls of the room. They were zoned into three segments that could be controlled by either Glass Crane or Tenorless, or both if they chose. I liked the idea of having multiple VJs working in congress with each other to create a unified vision, and I think they succeeded admirably, as did our laser specialist, Spilt, who did a great job of synchronizing his color patterns with the visuals through the three nights.

Alyssa: What successes did the team achieve while designing this experience?

Davis: I think creating the world’s first 6-way dance stack is definitely an accomplishment, and debuting a brand new deployment style with front/rear sub arrays which tested very well was a triumph for us as well. Just being able to organize productions on this scale, conducted equitably with our staff/artists, while only designed for 400 attendees or so per night, and getting away with it was our biggest achievement. Without the incredible logistical planning of Elias Walker and Mike Hollier, none of this would have been viable. The “bass cave” concept under the stage between the sub arrays was also a huge hit, and we’ll almost certainly be bringing that back and developing into the concept as well.

Alyssa: How did the design and setup of the sound system enhance the performances on the artists’ end? What qualities in producers do you look for when building your clientele at Hacienda?

Reference Sessions · Reference Sessions 001: Pathwey | Orlando, 9/14/24

Davis: I let all of our artists know that it’s OK to write sub notes far below F1 for playback at these events, and many of them are beginning to cut Reference Sessions dubs with extremely low sub notes that would not be audible on most touring rigs for these events. Dillard played a song with a 22hz sub note in it that was absolutely devastating, and had most of the patrons looking around at each other after they heard it the first time, likely because they’d never heard a sub note that low with anywhere near that kind of authority, it was an incredible moment for me and the sound team. We also have started commissioning Reference Sessions dub specials through different crews in Jamaica, which will mostly be heard at our events and are equipping our artists’ catalogs for the soundclash battles we’ll be bringing into the equation at upcoming parties. Shout out the One Sting Crew for our dub specials for this last event!

I don’t have any strict requirements for clientele at Hacienda per se, but I definitely have preferences in what I choose to platform at my events. I see the lineups for these always composed of eclectic varieties of bass music, whether that’s dubstep, grime, drum & bass, jungle, footwork, breaks, or whatever.

Alyssa: What role did the speaker layout and driver selection (e.g., 40/80 drivers) play in creating the physical presence amd clarity we felt?

Davis: There is a principle in acoustics/transducer theory known as Hoffman’s Iron Law. In layman’s terms, it states that you can only get deeper bass extension via larger drivers or by more electrical signal. There are obvious limitations inherent to the latter of the two options, as drivers have maximum headrooms that you cannot surpass without higher distortion figures, followed by a linearity, and lastly damage to the driver. Therefore we add driver size for extension, and for this reason we have spec’d very large subwoofer drivers (21” on the Axes, 24” for the Shermans), and a large number of them for more air displacement and coupling, for deeper extension. My old audiophile friend Mike Chafey always used to say “there is no surrogate for headroom” and I’ve subscribed to it in the design of my mastering studio and in the way that I spec deployments.

Having more drivers playing the same level drops the drivers’ individual levels, which in turn lowers their overall distortion figures. Good steering patterns make a huge difference, too. I’m one of few deployment guys who toes-in the mains for imaging purposes whereas most will fire the stacks straight back into the room for better coverage. I wanted to define a zone in the room where you would not only get an equivalent amount of L/R speaker in the space, but where the two sides would deliver strong localization and imaging qualities to the listener, which is usually outside of consideration for most live sound deployments. This space was defined directly in front of FOH and it was full of people all night who were probably hearing actual imaging out of a live sound PA for the first time.

A funny thing though, we actually ended up not using the attachments on the floodlights as they worsened the impulse response measurements. As a result, they were present but we didn’t wind up using them during the event. An interesting fact: if you have a speaker in a room that isn’t plugged into a powered amp, it will actually act as a passive resonator that will absorb the other speakers’ energy, so we hooked them up to a spare amp for the night that was powered but not receiving signal. I probably will be looking for lower distortion tops moving forwards as the subrange/bass/mids actually had lower distortion than the upper mids/highs on this particular rig, which bums me out a little because those Floodlights are probably my favorite top I’ve ever heard so far. They were designed in the 90s and our particular set of Floodlights was previously owned by Pink Floyd, before being lovingly restored and customized to improve upon the original specification by my dear friends Bill Weir and Citron Arbel at Trash Fence.

Since then, technology has advanced in ways that allow greater maximum output from tops, but Bill and I strongly feel that the Floodlight 760 represented a high water mark in live sound sonics that has never been replicated. I’ve been eyeing the Danley Jericho J7-95s and will be heading to the Danley factory to try them out soon. I absolutely adore the idea of synergy horns, on paper they should beat any non-coaxial top for impulse response measurements, and with 18 internal drivers per top the headroom is astronomical, and as a consequence the distortion figures at level should be much lower. They are rated to extend from 60hz-20k, but I suspect that using these in conjunction with TSW-718 kick bins crossed over circa 200hz, subwoofers, and infra subs will create a beautiful 6-way system. I just have to hear them and like them first!”

Alyssa: As a fan, I’d like to thank you and your team so much for choosing Denver for this incredibly special experience. The question is, what and where is next?

Davis: Deeper infrasonic extension, lower distortion figures, definitely soundclashes, bigger productions, and probably our own festival as well in the next year.

I’ve been in talks with the manufacturer of the largest infrasonic subwoofer driver in the world for super high end home theaters, which is outlandishly expensive, and requires the construction of the sub enclosure in the room it will be used. Their specs more than qualify them for use in live bass music, with 20,000 watt peak ratings, 35mm xMax, and 172L of air displacement. They would provide flat extension down to 8hz. However, the logistics of deploying an 80” subwoofer are extremely complex as you can’t fit a driver this big into an enclosure that would fit in the back of a truck or be able to fit through doors. They require a minimum enclosure size of 10m³ per driver! We would need to build rigid enclosures for these inside of the venue, which is not impossible, but would definitely add extra days to load in and require more staff to assemble.
I think there’s a lot more room for showmanship and spectacle in sound system culture, the most engagement I ever get on social media posts are pictures/videos of the big rigs I put together for these events. I know it resonates with people in a big way like it does for me, and I want to deliver more of what it seems like people really want out there, which is big fuck off sound systems that greatly exceed the sonic expectations of the listener.

As a patron, home is where the heart is, and Reference Sessions 002 brings a family-sized serving of master class engineering. This series is a tribute to the modern sound system, its impact, and the legends born from it, and these shows are one of a kind, precisely tuned, larger than life experience that can’t be missed. Let the system take you for a drive and let the team take the wheel; Reference Sessions is a breath of fresh air in the dynamic space of the musical counterculture.

“Every sound system has a story, and we are here to bring you that story.” - Matt Davis.

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