Reference is often described as the highest expression of REL. That is true, but it is only part of the story. To me, Reference is also the standard against which we test our understanding of low-frequency reproduction. It is where we ask the most difficult questions, remove the usual constraints, and find out how much closer we can come to the scale, timing, texture, and dimensionality of the original performance. The answers do not remain confined to our flagship models. The lessons we learn through Reference influence the way we think about every REL subwoofer.
My own road to Reference began long before I could help design one. I came up through high-end retail, spending long days setting up systems, moving loudspeakers by inches, listening with customers, and trying to understand why one adjustment brought a performance to life while another caused it to collapse. I was fortunate to encounter generous mentors who gave me hours of their time when they had no obligation to do so. They answered questions, challenged assumptions, and taught me to keep listening after I thought I had understood the answer. The road to Reference has been built in exactly that way, across decades through engineering, field experience, mistakes, refinements, and thousands of small decisions that gradually became something much larger. No.36 and No.35 are the newest results of that process, but they are not its conclusion.
Contents:
- Reference, the Standard
- How to Listen
- The Agreement Between Engineering & Listening
- Generational Lessons
- The Proving Ground
- Preservation of the REL identity
- The Pursuit Continues
Reference Is a Standard
I do not think of Reference primarily as a price point or a position at the top of a product range. Reference is a standard of behavior. It must produce immense scale without becoming slow. It must reach deeply without losing pitch. It must deliver physical impact without obscuring the fine structure of the recording. Most importantly, it must integrate so completely that the listener stops thinking about the subwoofer and becomes more aware of the performance.
Producing a large cabinet with a powerful amplifier and a large driver is relatively straightforward. Producing high output is not the same as reproducing music accurately. The real challenge is asking a driver to move through a considerable distance, repeatedly and at high level, while retaining the acceleration, stopping power, and low-level discrimination required to partner with the finest loudspeakers. The amplifier must provide current and control. The suspension must permit travel without binding or storing energy. The cabinet must remain inert. The filter architecture, connection method, and controls must allow the system to work with the loudspeakers and the room. Reference begins when all those demands are treated as one problem.
That standard applies regardless of scale. A more accessible REL does not need to reproduce the output of No.36 to benefit from the same discipline. It still needs to start and stop cleanly, preserve timing, communicate pitch, and integrate without calling attention to itself. Reference establishes the clearest version of those priorities. The rest of the range expresses them in forms appropriate to different rooms, systems, and budgets.
Reference No.36
Learning How to Listen
More than forty years ago, I listened first for the qualities most young listener’s notice. How loudly could a system play? How deeply could it go? How immediate was the impact? There is nothing wrong with hearing those things, but time teaches you that they are only the beginning. After thousands of hours in listening rooms, you become more interested in what happens just before and just after the obvious event. You listen for the resistance in a suspension, the character of a cone, the way energy stops, the texture inside a bass note, and the acoustic information that connects an instrument to the space in which it was recorded.
I sometimes compare the process to listening for the tumblers in a lock. You make a very small movement, and something opens. Then another small movement allows the next part to fall into place. Had you tried to force the dramatic result at the beginning, you would never have reached it. High-end audio often works that way. A series of seemingly modest improvements can suddenly allow the system to become quieter, more dimensional, more dynamic, and more convincing.
REL Sessions NYC 2026 Event
Listening at this level is not vague or mystical. It is a practiced form of correlation. I hear a behavior, connect it to a mechanical or electrical cause, communicate that observation to an engineer, and then listen again after the change. I work closely with a gifted driver engineer named Eric. After years of working together, our conversations can sound almost like code. I may tell him that I can hear the spider resisting motion or that the surround is contributing a particular character, and he understands the mechanical change I am asking him to explore. Thirty years ago, I could not have had that conversation. Experience has given us a shared language for turning what I hear into useful engineering direction.
This is why we do not design toward an effect. If the goal is simply to make something sound more dramatic, the work quickly loses its direction. We identify the primary limitation and address its cause. Sometimes the answer is greater amplifier reserve. Sometimes it is lower moving mass, a quieter cone structure, revised suspension geometry, better control of cabinet energy, or a more precise method of integrating with the room. The process is incremental, but the accumulated result can be profound.
Engineering and Listening Must Agree
Measurements are essential because they tell us what a design is doing and whether it can perform safely and consistently. They reveal frequency response, distortion, thermal behavior, excursion, compression, and the effects of a component change. They allow us to repeat a result and distinguish genuine progress from a favorable first impression. But a measurement cannot decide whether the system communicates the scale of a hall, the physical character of a piano, or the tension and release within a performance. That judgment requires listening.
REL Sessions NYC 2026 Event
Our process moves continually between the two. A listening observation must lead us toward a cause that can be examined. An engineering change must return to the listening room and prove that it improves the experience rather than merely producing a more attractive graph. We also test with music and film material that places sustained, repetitive demands on the system. A subwoofer cannot be considered successful because it survives one short burst. It must maintain control through extended high-amplitude passages, then recover instantly and reproduce the next quiet detail without carrying energy forward from the last event.
That balance is especially important in Reference because the available output can be seductive. There are moments in development when a new amplifier and driver combination begins producing enormous scale and everyone in the room feels the excitement. That is often when I suggest we stop, get lunch, and come back with fresh ears. The first success is real, but it cannot be allowed to set the standard for everything that follows. When we return, the questions become more exacting. Is there stored energy? Is the rear wave sufficiently controlled? Do we need a different amount or placement of internal damping? Does the driver remain quiet at low level? Does the amplifier preserve composure under repeated demand? Have we gained authority without losing nuance? The design is finished only when the answer holds across the entire operating range.
Every Generation Teaches the Next
A new Reference model does not begin by discarding everything that came before it. We start by identifying what the previous generation got right. The front-end architecture, connection principles, filtering, cabinet proportions, driver behavior, and system configurations all represent knowledge earned through earlier development and thousands of installations. Elements that remain exceptional are preserved. The opportunity is to improve the areas where new materials, new amplifier capability, or new manufacturing knowledge allow us to move forward.
The progression from No.31 to No.35 and from No.32 to No.36 demonstrates that approach. No.35 retains the accommodating cabinet dimensions of No.31 while introducing a newly developed 12-inch Pure Carbon Fibre driver with a finer 12K weave, revised mechanical architecture, greater excursion, a 900-watt Class AB/D amplifier, and a massive 17-pound toroidal transformer. The objective was not to alter the identity of the model. It was to create greater scale, strength, self-damping, and control while preserving the speed and elegance that made its predecessor successful.
No.36 begins with the scale expected from a 15-inch Reference design and extends it through a new 1,000-watt RMS Class AB/D amplifier, a Pure Carbon Fibre driver, deep extension to minus 6 dB at 15 Hz, and the control required to use that capability in ambitious music and theater systems. Dual Parametric EQ, REL High Level Connection, comprehensive low-level connectivity, and compatibility with AirShip Direct support precise integration. Yet the specifications are not the destination. Their purpose is to create greater ease at high level, greater quiet at low level, and a wider range over which the system remains composed.
Reference No.32
Reference as a Proving Ground
Reference gives us the freedom to investigate ideas at the highest level before practical constraints are applied elsewhere. That does not mean every Reference component simply moves into another series. Different products have different amplifiers, drivers, cabinets, applications, and price requirements. What travels across the range is the learning. We gain a better understanding of how cone materials store and release energy, how suspension behavior affects timing, how current delivery changes dynamic ease, how cabinet structure influences clarity, and how small setup adjustments alter the relationship between the subwoofer and the main loudspeakers.
Those lessons shape the questions we ask when developing every REL. Can the driver be lighter without sacrificing strength? Can the suspension move more freely while remaining controlled? Can an amplifier deliver the required current with less strain? Can the cabinet become quieter? Can the connection and filter architecture preserve more of the main system's character? Can setup be made more precise and repeatable? The solution will vary by series, but the standard remains recognizable.
Reference No.36
Field experience is part of the same feedback loop. Some Reference installations keep us in a customer's home for eight or ten hours. We move, listen, adjust, and listen again. Those days are demanding, but they are invaluable because real rooms expose problems that a development space may not. One small example came from hearing how the front of a large cabinet could settle under the weight of the driver. A minute change in mechanical leveling altered the launch of the leading edge and brought greater clarity to kick drums and other fast transients. That observation became part of the thinking behind the adjustable mechanical interface used on No.35 and No.36.
We learn the same way in dealers' listening rooms, at trade shows, and through installations involving single units, stereo pairs, and Reference Line Arrays. Each environment teaches us where adjustment range is useful, how placement changes room loading, and which details make setup more reliable. When a practical improvement proves its value repeatedly, it becomes part of the knowledge carried into future products. The laboratory tells us whether an idea works. The field tells us whether it works in life.
Preserving the REL Identity
Progress matters only if we preserve the qualities that define REL. More output cannot come at the cost of speed. Greater extension cannot produce overhang. More sophisticated adjustment cannot replace careful placement and listening. A new material is useful only if it improves the performance, and a new technology earns its place only when it strengthens the connection to music and film.
That philosophy explains why REL subwoofers are designed to support the entire system rather than operate as separate effects devices. When low frequencies are restored with the correct timing, level, and extension, the benefits reach far beyond bass. The soundstage opens. Images gain dimensionality. Dynamic contrasts become more natural. The character of the recording space becomes easier to understand, and the main loudspeakers sound more complete. The subwoofer can be heard in the sense that its contribution is unmistakable, but it should not be heard as an isolated source.
This is the standard that Reference makes most visible, and it is the standard we carry into every product we make. The scale changes. The engineering solution changes. The room and system for which each model is intended change. The essential purpose does not.
The Road Continues
No.36 and No.35 represent the fullest expression of what we know today. They combine the accumulated lessons of previous Reference generations with new advances in drivers, amplification, mechanical control, filtering, and integration. They are capable of extraordinary authority, but their real achievement is the way that authority remains connected to speed, subtlety, and the smallest details of a performance.
John Hunter, REL Acoustics Chief Engineer
I am proud of where the road has led, but Reference has never allowed us to believe that the work is complete. Every new design creates a clearer view of the next question. Every installation teaches us something about rooms and systems. Every listening session refines the connection between what we hear and what we must change. The responsibility is to remain curious, resist easy answers, and keep learning.
That is the road to Reference. It is not a destination defined by a model number. It is the continuing pursuit of a standard, one that begins with our most ambitious work and influences every REL subwoofer that follows.
Measurements guide the engineering. Music makes the final decision.
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