Reviews of Attainable Hi-Fi & Home-Theater Equipment

Reviews of Attainable Hi-Fi & Home-Theater Equipment

If you’ve never heard of Paul Hales and his Hales Design Group, you’re probably younger than 40, or weren’t into audio in the 1980s or ’90s. I was in my 20s in the ’90s, and in my budding-audiophile stage. I religiously read Stereophile and other audio magazines, and I lusted after the latest and greatest high-end speakers. Some of those speakers were made by Hales—I remember listening to their Revelation and Transcendence models at audio shows and local audio shops. At the time, their sound quality was some of the best available.

In 2000, Paul Hales left the Design Group to become the director of research and development for the loudspeakers made by QSC Audio, which specializes in professional audio gear and sound systems for commercial movie theaters. Four years later, he left QSC to form Pro Audio Technology, which provides professional-level home-theater speakers, subwoofers, and amplifiers for the home screening rooms of Hollywood directors, A-list celebrities, and wealthy CEOs.

Which brings us to Theory Audio Design. Hales founded the company in 2018 as a means of applying the same professional-level philosophy to residential and, beginning in 2021, commercial applications. He explained to me that after he’d finished designing and installing the sound systems of his clients’ dedicated screening rooms, they wanted similarly pro-grade sound in their living rooms. Thus was born the idea of a high-end soundbar. Theory Audio Design designed three soundbars to precisely match the widths of the 65″, 75″, and 85″ flat-screen TVs typically found in living-room systems that don’t use a projector.


Hales thought the best fit for my surround-sound system, with its 92″-diagonal screen, would be Theory’s Sys5.2.2.8515, which includes their 85″-wide sb85 soundbar. This system also contains two subwoofers with 15″ drivers, and at first I balked, thinking they’d be overkill for my room. But Hales thought it would be best that I review one of their standard prepackaged systems. I thought that made sense. In addition to the sb85 soundbar and the two sub15 subwoofers, the Sys5.2.2.8515 system includes two sb25 speakers for the left and right surround channels, two more sb25s for the Dolby Atmos height channels, and an ALC-1809 controller-amplifier to power and configure the speakers. The retail price of $12,300 (all prices USD) at first struck me as far too high for a soundbar-based system.

Then I listened to it.


The central component of Theory’s Sys5.2.2.8515 system is the sb85 passive soundbar itself ($2400 when bought separately). Its size and weight dispel any notion that it belongs in the category of soundbar. Its width of 75.25″ matches that of an 85″ TV—but it’s only 9.5″H x 3.8″D. The side and rear panels are made of extruded aluminum, the baffle of machined MDF. In back, two recessed channels run the full width of the rear panel. Two Z-clips can be screwed into these channels, to attach to companion clips affixed to a wall, to hang the sb85 directly below the screen. The sb85 weighs 72 pounds, so be sure that the wall clips are screwed into studs or something similarly strong. In fact, because the sb85’s top and bottom are rounded, wall-mounting is, for now, the only way to secure it, though Theory will soon introduce a tabletop stand. To connect the three channels to the amp, the sb85 has three sets of spring clips that can accept bare wire of up to 12 gauge.

Under its grille, the sb85 resembles three sb25 speakers (described below) laid end to end. Each set of drivers serving one of the three front channels is in its own subenclosure. The tweeters for the left and right channels are at the extreme left and right ends of the sb85. Theory calls these 1.4ʺ tweeters “advanced polymer compression drivers.” Unlike a conventional dome tweeter, in which the dome’s surface radiates sound directly into the listening space, a compression driver has a chamber in which a diaphragm vibrates, soundwaves then emerging through a hole in the front of the chamber and dispersing sound into the room. The area surrounding the hole is usually shaped like a horn, as in speakers from Klipsch or JBL. In Theory speakers, however, each compression driver sits at the bottom of a circular concavity machined into the MDF baffle, its proprietary axisymmetric profile shaped to optimize off-axis performance. In addition to the three tweeters are six 5″ midrange-bass drivers with carbon-fiber cones, two per channel. To augment the sb85’s bass response, each subenclosure/channel has two front-venting ports.


The use of compression drivers, says Theory, makes possible the sb85’s claimed high power handling of 200W and very high sensitivity of 94dB/W/m. The soundbar’s maximum output is specified as a deafening 117dB/channel, or >124dB with all three channels driven, and its frequency range as 58Hz-23kHz—no tolerance is given, but from my listening, 58Hz seems a realistic spec.

The Theory sb25 satellite speaker ($850 each) measures 21.5″H x 9.5″W x 3.8″D, weighs 23 pounds, and has the same driver complement and specs as each channel of the sb85: a 1.4″ compression tweeter, two 5″ carbon-fiber bass-midrange drivers, two front ports, and identical frequency response, maximum output, and sensitivity. If you don’t use a Theory soundbar, the sb25 is designed to be used for any channel of a home-theater system other than an LFE channel: front left, right, or center; surround, rear, or height. The sb25 has a Z-clip that can be attached to its rear panel at top or bottom, depending on how you want the sb25’s tweeter positioned; when used as a center-channel speaker, it can be laid on its side and mounted on the wall below a display or screen.


Because Theory’s sub15 subwoofer ($1500 each) is a passive design, it lacks a powered sub’s rear-panel controls—all it has is a single pair of spring clips for speaker cables. I thought my Paradigm Servo-15 V2 subwoofer was pretty big, but the sub15 makes it look and feel like a toy at 23.5″W x 21.3″H x 19.8″D and 76 pounds. Under its removable cloth front grille is a 15″ driver with a treated-paper cone, a cloth surround, and a 4″ voice-coil. In the bottom corners of the baffle are two large ports. The sub15’s specified frequency range is 22-125Hz, its maximum output a bone-rattling 124dB.

The brains and brawn of the Theory system are the ALC-1809 speaker controller and amplifier ($3500). Stuffed into a slim case measuring 17″W x 1.75″H x 15″D and weighing 13 pounds are nine class-D amplifiers to power as many channels, and a digital signal processor (DSP). A single ALC-1809 can be configured for any combination of speakers, from 2.0-channel (two main front speakers, no sub) to 7.2-channel (three front, two surrounds, two rears, two subs), or 5.2.2-channel Dolby Atmos (three fronts, two surrounds, two heights, two subs) arrays. A single ALC-1809 can control and power up to three subwoofers. If you have more than nine channels and speakers, you can add additional ALC-1809s.


The ALC-1809 has eight balanced input connectors, and comes with Euroblock-to-female-XLR adapters. The nine speaker outputs are labeled 0 through 8. Why nine outputs but only eight inputs? Channels 0 and 1 are both subwoofer channels, and both receive the same signal. The ALC-1809’s power-output specs are 300W into 4 ohms for the first three channels, and 100W into 4 ohms for the remaining six.


Setting up the Theory Sys5.2.2.8515 system was more complex than with other home-theater speaker systems I’ve reviewed, mostly because of the ALC-1809 controller-amplifier’s input and output connectors. I needed to use RCA-male-to-XLR-female interconnects from my Anthem MRX 720 A/V receiver to the ALC-1809’s inputs, using the provided Euroblock-to-female-XLR adapters. I worried about introducing noise or hum by connecting my AVR’s unbalanced output to the Theory’s balanced inputs, but I needn’t have—the result was dead quiet. The ALC-1809’s speaker outputs are also Euroblock connectors, so I removed the banana-plug terminations from my speaker cables and inserted the cables’ bare wires into the Euroblock connectors. The final snag was with the two sub15 subwoofers—I’ve run unbalanced (RCA) interconnects through my walls to each subwoofer position, but the sub15s require actual speaker cables, which I ran across the floor.

I set the sb85 soundbar atop a low stand below my screen, which put it about 11′ from my listening seat. I used clamps to keep it propped up on my stand—I didn’t want to drill holes in my walls for the Z-clips, and Theory’s tabletop stand wasn’t yet available. The two sub15 subwoofers went on either side of the sb85, some 10′ from my seat. I positioned the two sb25 surround speakers directly to the sides of my seat, around 5′ away. But setting up the two sb25s for the Dolby Atmos height channels put me in a bit of a quandary—ideally, I’d have liked them mounted on the ceiling (using one of Theory’s many suggested mount options), halfway between the room’s front and rear walls. Lacking a good way of temporarily mounting them there, I put them high on the front wall near the ceiling, firing into the room. This put the speakers 13′ from me as I listened.

The ALC-1809 controller-amp must be configured using Theory’s PC-based Music and Surround Automator software. After the program has been downloaded and installed, input the number of speakers and subwoofers you’re using, their positions, the distance of each speaker from your listening position, and each speaker’s proximity to corners. That done, Automator calculates the ideal crossovers, delays, and equalization settings, and outputs that configuration to the ALC-1809 via a USB connection from your computer.


Two things about the Theory Music and Surround Automator:

First, Paul Hales insists that any room-correction system running in your processor or AVR should be turned off, the speaker-distance settings set to the lowest possible amount (e.g., 1′), all speaker-volume settings should be identical, and the subwoofer crossover set to the highest frequency possible. This puzzled me at first—Anthem Room Correction (ARC), which is built into my Anthem AVR, has enhanced the sound of my system with almost every array of speakers I’ve used. Hales explained to me that because he knows the performance parameters of the Theory speakers and subwoofer, their outputs can be optimized better by the ALC-1809 and Automator than by any room-correction system. When the Automator has crunched its numbers, there aren’t many parameters you can tweak—you can adjust only the bass level. I tried varying the bass level, up and down, from what Music and Surround Automator had come up with, but ultimately concluded that I couldn’t improve on it. I could still have used ARC to tweak the level or distance for each speaker had I not liked what the Automator was doing—but I never felt the need.

Second, Theory constantly tweaks the Automator software, and regularly sends out updates. When you update the ALC-1809 controller-amp with the latest software revision, you’ll get the benefit of better sound. Hales likened this to the Tesla automobile, the performance of which can be tweaked over the air. Each Theory speaker is updated individually—during the time I had the Sys5.2.2.8515 system up and running, the sb85’s software was updated to v1.2, the sb25’s to v1.3, and the sub15’s to v1.1.

Listening to movies

The first thing that struck me about the sound of Theory’s Sys5.2.2.8515 system was its high output and dynamic range. They were unlike anything I’d ever heard from a soundbar or on-wall speaker system. In fact, this system’s powerful sound rivaled that of any system of freestanding speakers I’ve heard. It was all the more remarkable when I looked again at these speakers and was reminded that they’re only 4″ deep. I’d have expected to hear some cabinet colorations, but all I heard was clean sound.

As I watched the BD edition of Godzilla: King of the Monsters (2019), the Sys5.2.2.8515 kept up with every explosion, gun shot, and literally monstrous foot stomp. These effects shook my walls. I was blown away that a system of wall-mounted speakers could do this in my room.

With identical drivers in each speaker or subenclosure, the Theory system was ideal for surrounding me with coherent and seamlessly realistic sound. In chapter 1, when Dr. Emma Russell (Vera Farmiga) and her daughter (Millie Bobby Brown) enter Monarch Outpost 61, a pyramidal structure in China, I got a real sense of a vast space. When the birth of Mothra goes haywire, the Theory system easily reproduced the resulting cacophony. The plot of this monster movie is average at best, but the Sys5.2.2.8515 system’s soundfield was so realistic that it kept me engaged from start to finish.


At first I was concerned that the sb25s mounted high on my front wall weren’t ideally placed to fully reproduce the overhead surround effects of this film’s Dolby Atmos soundtrack. But in chapter 2, when the Monarch organization visits the cabin of the reclusive Dr. Mark Russell (Kyle Chandler), they make an impressive landing in their V-22 Osprey tiltrotor aircraft. This scene is shot from directly above the V-22, and through the Theory system I could easily follow the sound of the props as it moved seamlessly from the sb25 height speakers to the sb85 soundbar, accurately tracking the Osprey’s onscreen position. This scene also showcased the excellent timbral matching of the sb25s to the sb85.

To test dialog intelligibility, I played the BD of Bloodshot (2020), in which Vin Diesel plays the titular character, an elite soldier who dies, is brought back to life with advanced technology, and discovers that he now has superhuman powers. Even in the best circumstances, Diesel isn’t the easiest actor to understand—he growls and mumbles. But through the Theory Sys5.2.2.8515 his deep voice had plenty of weight and was perfectly intelligible—I never had to turn on the subtitles, or reach for the remote to boost the center-channel volume. In chapter 5, when Diesel’s voice bounces back and forth between the center channel and the surrounds, it sounded exactly the same regardless of where it seemed to emanate from. These scenes also showed how easily the sb25 surrounds cast a wide soundfield—my surround system usually includes pairs of rear and side surrounds, but with just two sb25s pulling side-surround duty, I didn’t miss having speakers behind me.

Another impressive element of the sound of the Theory Sys5.2.2.8515 system was the depth of bass reproduced by its two sub15 subwoofers. Chapter 6 of Bloodshot includes a huge crash of a semi truck into an SUV, followed by a gunfight and explosions. Through the sub15s, the explosions were deep and guttural—I didn’t only hear them, I felt them in my bones. The bass was evenly distributed throughout my room—I could hear and feel it no matter where I sat. I’d expect some bass overhang with ported enclosures, but the sub15s did a remarkable job of minimizing this, sounding as tight as any sealed-box subwoofer I’ve had in my room.


In fact, the Sys5.2.2.8515 speakers didn’t disappoint in any way, providing a genuinely cinematic experience, with dynamics surprising from an array of shallow on-wall cabinets. Although Theory markets the Sys5.2.2.8515 as a living-room system for its jet-set clientele, it could easily serve in most people’s dedicated home theaters. The only problem I’d foresee for me would be how much I’d annoy my family—I’d want to play it loud all the time. The Theory system’s sound was so clean at high volumes that I didn’t realize how loud I’d set the level until my wife came downstairs to complain.

Listening to music

As good as the Theory sb85 soundbar was for home theater, its left- and right-channel drivers are only a fixed 4.5′ apart, a distance less than ideal for good stereo separation when playing recordings of music and listening from 11′ away, as I do. Thinking that using two sb25s as a stereo pair of speakers would be a better test of the Theory system’s musicality, I put the sb25s on stands and toed them in for ideal stereo imaging. Of course, any such change in number and/or positions of Theory speakers will require that you use the Music and Surround Automator to configure the new setup, then upload the new settings to the ALC-1809. You could also set up a 2.2 system, using the two subwoofers.

All that done, the sound quality of the ALC-1809 and sb25s alone was jaw-dropping. Again, the dynamics were incredible. In “Use Me,” from Patricia Barber’s Companion (16-bit/44.1kHz FLAC, Premonition/Blue Note), Michael Arnopol’s plucked double bass sounded forceful and vibrant. Ruben Alvarez’s percussion was also very energetic and impactful. Barber’s voice was solidly at the center of the soundstage, its image huge and floating in a space above the tops of the sb25s. This was all the more remarkable as the sub15 subwoofers were turned off! I double-checked: The ALC-1809 was indeed set up with no subwoofer.


I then went into my Anthem AVR’s Profile 2 and made sure the subwoofer channel was turned off there as well. As with my surround listening, I heard no cabinet colorations from the Theorys—the sound was very balanced throughout the audioband. The sb25s produced bass as deep as a large minimonitor’s. Barber’s Hammond electric organ in “Use Me” sounded a bit strident, but remember, the speakers were playing loud, and they may have been interacting with my walls. To make sure, I turned the volume down and played “The Seductress,” from trumpeter Wynton Marsalis’s Standard Time Vol.3: The Resolution of Romance (16/44.1 FLAC, Columbia). Sure enough: When Marsalis hit high notes, the sb25s didn’t sound harsh.

I’ll review the Theory sb25 in more depth in a forthcoming review; for now, suffice it to say that I was blown away by their performance with music.


I didn’t have a comparable soundbar against which to test the Theory sb85, but I don’t think there is anything comparable to it—that is, another soundbar that can match its sound quality or dynamic output. However, I did have a pair of PSB’s PWM1 on-wall speakers ($799 each), which are of similar size and shape. The smallest model in the PWM line, at 28ʺH x 6.5ʺW x 4ʺD the PWM1 is taller and narrower than the sb25, but about the same depth. The PWM1 has a 1″ titanium-dome tweeter and two 4″ midrange-woofers.

I was immediately struck by the differences in tonal quality between these speakers. The PWM1 had the classic PSB house sound, sounding slightly darker and richer through the midrange than the Theory. The sb25 was more dynamic, and slightly leaner through the midrange and highs. I couldn’t say that one sounded better than the other, but if your room is particularly “live” and reverberant the sb25’s high-frequency output might be too much, leaving the PWM1 the better choice. But if you listen to music at loud levels, the sb25 excelled at conveying dynamic content. Midway through “Code Cool,” from Patricia Barber’s Smash (24/192 FLAC, Concord Jazz/HDtracks), Jon Deitemyer’s percussion explodes from relative quiet. The Theory sb25s reproduced this wide dynamic range better than could the PSB PWM1s.


Comparing the Theory sub15 to my own subwoofer, a Paradigm Servo-15 V2, I found that my Paradigm could keep up with the Theory in terms of deep bass. Both subs could hit 20Hz with ease, but the Theory had the Paradigm beat in quantity of bass, easily filling my room with low-end frequencies I could feel rather than hear. Mind you, you need to find room for the sub15—it’s a big subwoofer.

With two sub15s, I was struck by the evenness of bass throughout my room. In the opening shot of Blade Runner 2049 (2017, BD edition), an extreme closeup of a human eye, the depth of bass in my room from two sub15s was breathtaking—my single Paradigm Servo-15 V2 didn’t quite produce the same authority.


Theory Audio Design’s Sys5.2.2.8515 system makes a fact of an audacious claim: that a soundbar, a component category associated with low fidelity, can achieve sky-high sound quality. I hadn’t expected to be impressed by a soundbar-based system, but my listening for this review has shown me how well it might work in many rooms—the big but sleek sb85 soundbar placed just below my screen, and four sb25s mounted on the walls, took up no floor space. Sure, those two sub15 subwoofers were huge, but they could easily be tucked away in room corners in many rooms or one could opt for Theory’s smaller sub12 subwoofers.

Having listened to and evaluated the Theory Sys5.2.2.8515 system, I’m convinced that it can compete with any surround system of freestanding speakers and amplifiers of comparable price, and match or even exceed the dynamic range of many large tower speakers. The only area in which the sb85 soundbar itself came up short was in soundstaging—with its left- and right-channel drivers so close together and unable to be moved farther apart, there’s just not enough space between them for the sb85 to produce a soundstage of realistic width when I sat 10′ or farther away. However, that could be remedied by replacing the sb85 with three sb25s.Theory

Finally, I see the value in the Sys5.2.2.8515. Although $12,300 is a lot of money, it buys the equivalent of seven speakers, two big subwoofers, and a controller-amplifier packing enough power to add a lot of value. And with the ALC-1809, you wouldn’t need a sophisticated room-correction system in your processor or AVR to get state-of-the-art sound.

If you’re looking for a highly dynamic home-theater speaker system that doesn’t take up a lot of floor space, I highly recommend that you give the Theory Sys5.2.2.8515 system a listen—it just might blow you away as it did me.

. . . Vince Hanada

Associated Equipment

  • A/V receiver: Anthem MRX 720
  • Amplifiers: Integra DTA-70.1, NuPrime IDA-16
  • Speakers: Definitive Technology: BP8060ST mains, CS8060HD center, ProMonitor 1000 surround and height, Mythos Gem rear surrounds. Angstrom Ambienti in-ceiling height speakers.
  • Subwoofer: Paradigm Servo-15 V2
  • Source: Oppo Digital BDP-95 universal BD player
  • Interconnects: Analysis Plus Super Sub
  • Speaker cables: Analysis Plus Blue Oval
  • Projector: Epson Home Cinema 3500

Theory Audio Design Sys5.2.2.8515 5.2.2 Dolby Atmos Surround Speaker System
System Price: $12,300 USD.
Warranty: Five years, speakers and subwoofers; three years, controller-amplifier.

Theory Audio Design, LLC
25741 Atlantic Ocean Drive, Suite B
Lake Forest, CA 92630
Phone: (949) 245-0505