In the first part of this series, I outlined the key design considerations for my new media room, explained my design process, and described the more exciting aspects of the room’s construction. Once the walls were ready for millwork, I proceeded to install the lighting, followed by the carpet and chairs, and, finally, the woodwork details on the wainscoting and coffered ceiling. With all of that in place, the room was starting to resemble the bones of a theater, and I was excited to begin building and installing the cabinetry destined to conceal the subwoofers, stereo components, and home-theater electronics.
It was also time to order my in-wall speakers, so I reached out to KEF America’s vice president of marketing, Stephanie Scola, with whom I had worked during past reviews and in purchasing my KEF XQ40 floor-standing loudspeakers and matching XQ2c center channel (which I still use in my living room). After I gave Scola an overview of my room, my speaker requirements, and the dispersion characteristics I was after, she outlined the products she thought would work best in my space. She also put me in touch with David Kroll, KEF America’s vice president of sales, who is responsible for all of KEF’s in-wall products.
Kroll confirmed Scola’s recommendation that I use four KEF Ci3160RLM-THX in-wall speakers ($1999 each, all prices USD) for the surround channels, four Ci200RS-THX in-ceiling speakers ($999 each) for the Atmos height-effects channels, and one Ci5160REFM-THX in-wall speaker ($10,999 each) for the center channel.
After our initial discussion, Kroll scheduled a video call and took me on a detailed virtual tour of KEF’s 9.10.6 Dolby Atmos THX-Certified Music Lounge theater in New Jersey. We spent about an hour online discussing various topics, such as wall-construction techniques, appropriate cavity volumes for all the in-wall speakers (this information is available on KEF’s website), wall materials, and room treatments. I was especially keen to learn about the cavity-volume requirements—even though I purchased nine in-wall speakers, five of them never saw the inside of a wall. All four surround speakers were installed in damped towers with internal volumes matched to the ideal cavity volumes specified by KEF for the best low-frequency response. Likewise for the center channel: behind the baffle on which the center-channel cabinet is mounted is a sizeable 4′H × 6′W window.
Toward the end of our video tour, Kroll and I discussed the technological characteristics of acoustically transparent movie-screen materials. Kroll took me to school, describing the advantages and disadvantages of woven versus perforated screens. He then put me in touch with the folks over at Seymour-Screen Excellence, as they had designed and built the 160″ screen used in KEF’s reference theater. My experience with SSE could not have been more positive. I initially contacted Paul Muto, SSE’s sales and marketing manager, who later connected me with Chris Seymour and SSE’s operations director, Evan Zerby, to discuss frame and material options and firm up an eventual screen size.
I had designed the front corner cabinets in my room to flank a 110″ screen, but this was based on a 2.5″-wide frame. Now I was unsure if a 110″ screen would fit, as SSE’s Reference frame is 3.5″ wide. I had also hoped to explore the possibility of utilizing a custom-designed hinge system that would provide easy access behind the screen. As reviewers, we need access to everything in our rooms; my eventual screen would hide the center channel speaker, two quadratic diffusers, and all the wiring tying my two-channel system together. Zerby scheduled a design meeting with one of their engineers, who needed all of five minutes to produce a solution.
After a quick video call a few days later, I was sent a live graphic of what they had in mind, and two days after that, I had a copy of the graphic in my inbox along with a spec and a quote for a 110″ Reference-series frame equipped with a trick top-mounted hinge system and SSE’s Enlightor-Neo transparent fabric. Kroll was right: the quality and performance of SSE’s screens are fantastic, and I cannot thank their team enough for their ingenuity and willingness to work on such a unique project.
While waiting for the screen and speakers to arrive, I finished building the subwoofer enclosures and wrapping up some final cabinet details before installation. With all four subwoofer cabinets installed, one in each corner of the room, I could install the corner cabinets at the front of the room. The left cabinet contains two slide-out shelving units for movies and SACDs, plus a drawer I fondly refer to as the remote graveyard. The right cabinet houses all the home-theater electronics, including an Anthem AVM 90 Dolby Atmos processor, two Anthem MCA 525 Gen 2 five-channel amplifiers, an Oppo UDP-203 universal Blu-ray disc player, a Zappiti Pro 4K HDR Audiocom Cinema Edition media player, and a Zappiti NAS for ripping and storing anything from a DVD to a 4K Blu-ray.
Using a tower-like cabinet to house all the home-theater equipment posed a few challenges. The first was access: even though I do not review home-theater equipment, I still need access to the backside of the components. Space and cable length constraints made using a preassembled pivoting steel chassis impossible, so I used 150-pound steel sliders to make each component tray retractable. Cooling was the next challenge, as space was tight; to solve this problem, I installed an AC Infinity AIRCOM T8 cooling unit on top of the lower Anthem power amplifier and an AC Infinity AIRCOM S9 atop the upper amplifier. The lower amplifier powers the center channel and height-effects speakers, and it runs pretty hot without cooling. The upper amplifier powers just the surround speakers and does not need additional cooling, but I figured I would install a smaller unit for movie marathons—just in case. Both fan units draw cool air from under each amplifier, up over the heat sinks, and exhaust it to the rear of the cabinet, which vents behind the screen. I have both units set to run the fans at level 3 (of 5), and even during a John Wick marathon, temperatures remained steady at 36°C.
I built three ventilated lower cabinets between and below the two tower cabinets to house most of my two-channel gear, with each component sitting on a retractable base. Power from the dedicated 20A wall outlet is pulled through a Shunyata Sigma HC power cable to a Shunyata Denali 6000/S v2 power conditioner, and this serves a pair of Classé Delta Mono amplifiers, an Audio Research Reference 6SE preamplifier, a Pro-Ject RPM 10 Carbon turntable, a Parasound JC3+ phono stage, and a T+A MP 3100 HV streaming SACD player, all connected via Shunyata Alpha v2 NR power cables. I continue to use an Intel NUC running Roon as my music server, but that’s stashed inside the wall on the other side of the room alongside the previously mentioned “noisier” components.
Acoustic treatments
Figuring out how to acoustically treat a room that had yet to be built proved to be a tricky endeavor. I had initially intended to hire a professional to measure, model, and treat my room, much like Jeff Fritz, SoundStage!’s previous editor-in-chief, did when he built his Music Vault years ago. Unfortunately, I could not find an independent consultant in Canada who offers these services. Many high-end audio stores in Vancouver and across Canada will do this, but, understandably, they typically recommend only acoustic products they sell, and I wanted an impartial expert who could tell me exactly what I needed—and, more importantly, what I did not. Without such a resource, I was forced to take a big step back and reconsider how I, lacking a background in acoustics, would proceed.
I started by searching online for easy-to-use independent modeling software online that identified room modes. Room modes are the collection of resonances in a room that cause peaks and nulls in frequency response in locations throughout the room. Unfortunately, to my knowledge, none of these software applications takes the next step and recommends the type and quantity of treatments to manage RT60 (reverberation time).
So, I abandoned my attempts to find an easy solution and decided to try to figure things out for myself. I knew step one would be to design around the problems I could not control, so I modeled my room using Room EQ Wizard (REW) software to identify my room modes and where the peaks and nulls would occur. If you look closely at the pictures, you will notice the front row of seating is slightly offset to one side, yet aligns precisely with the center of the broader side of the room, forming a perfect equilateral triangle between my main speakers and the listening position while avoiding the mid-room null.
From there, I was dead in the water until my room was complete. I needed to measure my completed space with things like carpet, furniture, and A/V equipment in place, to correctly identify the room response at the listening position. Only with those measurements could I start considering the type and quantity of required acoustic treatments. The good news was I had no windows to contend with, my quasi-perimeter bass trap was complete, I’d upholstered the walls in a spun-silk material, and I’d used thick carpet and underlay, so even without any on-wall acoustic treatments, the space didn’t sound too bad in terms of reverberation times. But there was room for improvement.
Room decay of untreated new room
Because I use my room for both two-channel and multichannel listening (music and movies), I needed to decide which was more important to me, because the process for treating a home theater is typically quite different than treating a room intended for two-channel listening. I chose to treat for two-channel listening because a desire for improved sound from my music system was what had initially prompted the redesign of this room. Also, the principal treatment locations (first reflection, back wall, corners, second reflection) are the same for both room types. Moreover, my Anthem AVM90 processor, which I use for all multichannel material, can partially correct for room resonances through its onboard ARC Genesis room-correction software.
I knew that the best place to treat in a room, two-channel or otherwise, was the first reflection point, so that’s where I started. I built and hung a pair of 48″H × 36″W × 3.5″D absorption panels filled with 3″-thick Rockwool Comfortboard 80 (average noise reduction coefficient = 0.90, 125–4000Hz). I built a ½″ air gap behind each panel, as doing so can help extend the panels’ absorption bandwidth so long as the air gap is less than or equal to the panel thickness. I also built a sound cloud to treat first reflections from the ceiling, comprising three 3″-thick 2′ × 4′ panels placed side by side, suspended 2.75″ from the ceiling.
With my first reflection points treated, and before treating the back wall, I played a couple of tracks and immediately heard an improvement in imaging, soundstaging, and bass resolution. However, I also noticed the room was already starting to sound a hint dead or flat, so I pulled the trigger on some diffusion products from a US company called GIK Acoustics to help restore some liveliness to the room. I had an idea of what I thought might work. Still, to ensure I was on the right path, I spent some time using GIK’s Room Acoustics Visualizer and Acoustic Panel Calculator tools and filling out their Acoustical Advice Form before being provided a contact whom I could call to make sure I was on track.
My approach to treating the back wall and corners was to use a pair of CT Alpha Series Corner Bass Traps and four 6″-deep 6A Alpha Pro Series absorbers, all equipped with GIK’s slatted one-dimensional diffusion panels. I also ordered, based on feedback from GIK’s acoustics engineer, three 2A Alpha Pro Series panels equipped with GIK’s two-dimensional diffusion panels for above the listening position, and a pair of their recently released 19.7″W × 45.9″H × 6.2″D Q7D quadratic diffusers (seen earlier flanking the Ci5160REFM-THX behind the screen). The measured effectiveness of these QRDs is 350Hz to 3kHz, and I was taken aback by how large an impact they made towards implying a vaster soundstage.
Finished room
After 19 months of construction, learning, measuring, and listening, I completed my room in early March of this year. Most of February was spent measuring and listening, and I will admit to getting sucked into an paralysis vortex of speaker positioning, experimenting with acoustic treatment locations, and so on. In the end, the time spent was well worth it; take a peek at the measurements below, and you’ll see some stark improvements over my previous room.
New room frequency response (1/12-octave smoothing)
Room decay of treated new room
Despite the measured improvements, it was how music and movies sounded that mattered to me, and I am happy to report that this room provides a far more satisfying listening experience than before.
The 37Hz null in the middle of the room before this adventure remains, but I’m elated that it’s not as severe. Bass sounds deeper, cleaner, and punchier than I ever heard in my old room, and I can more easily hear subtle nuances that previously eluded me, thanks to the revamped room’s much lower noise floor—32.1dB, versus 37.9dB in the old room. The most significant improvement is the scale of the soundstage. Yes, the speakers now sit over a foot further apart, but while experimenting with the location and type of acoustic treatments all over my room, I replaced the quadratic diffusers with absorption panels. In doing so, I heard an appreciable improvement in image focus, but it came at the expense of depth and a more familiar-sounding soundstage width. Of all the treatments I have installed, these made the most audible improvement.
To this reviewer, the new room looks, sounds, and functions much better than the previous one. There’s now easy access to all the electronics in the room. I’ve managed to achieve all ten of my design goals, and all the components (except the Audio Research Reference 6SE and cooling units) are controlled using a new Control4 system providing one-touch operation, through either a remote handset or a handy tablet app (iOS/Android). In short, the new room is as fun to use as it is to listen in. In fact, I’ve already completed one review in this space. It’s my review of Simaudio’s Moon 891 streaming preamplifier, which was published on SoundStage! Ultra on October 1.
Aron Garrecht
Contributor, SoundStage!
Equipment List
- Loudspeakers: Paradigm Persona 7F
- Power amplifiers: Classé Delta Monos
- Preamplifier: Audio Research Reference 6SE
- Media player: T+A MP 3100 HV
- Music server: Intel NUC running Roon
- Turntable: Pro-Ject RPM 10 Carbon with Sumiko Starling Cartridge
- Phono stage: Parasound JC3+
- Power conditioner: Shunyata Research Denali 6000/S v2 w/Shunyata Research Sigma XC cable
- Power cords: Shunyata Research Alpha v2 NR
- Speaker cables: Kimber Kable Select KS6063
- Interconnects: Kimber Kable Select KS1126
