Home Movie Theaters

During this early stage of construction, two windows had to be sealed to create a space that would be dark and sonically isolated. Once the windows were closed up, Karni's team built the walls of the theater on the floating floor and, for the ceiling, created a grid structure that attached to the original room with special acoustic springs to provide damping. The walls were a double-stud construction with acoustic springs in between, two layers of mineral wool, and two layers of drywall. "This system is very effective, not only for isolation, but to reduce bass buildup caused by room modes," Karni advises. Or as Nagar put it, "It creates a resilient structure that acts like a resonant bass-trap system." An acoustic door was installed as the final touch to the soundproofing.

Acoustic Ambitions
The overarching goal of Karni's acoustical treatment plan was to facilitate huge, evenly dispersed sound throughout the room. In addition to building multi-layered walls and filling them with insulation, Karni's team constructed an elaborate (and very heavy) wood baffle wall in the front of the theater to house the three front speakers and two front subwoofers, which are situated above the main speakers and separated from the baffle with sheets of rubber. The 19 or so inches of space behind the baffle was filled with high-density acoustic foam, and 0.7-inch-thick birch panels were installed around the speaker openings with a final layer of acoustic foam to prevent any comb filtering effects from the screen that would be placed in front of the speakers.

The theater's back wall comprises what Nagar calls a custom designed "equipment cupboard" with space for an A/V rack, two subwoofers, the two surround speakers, vents with silencers for the dedicated AC system, and the video projector. Like the front baffle wall, the cupboard was filled with acoustic foam. "This acoustic treatment resulted in evenly dispersed bass with a 0.2-second reverberation time under 500Hz," Karni says, which translates into "very tight and detailed bass."

The next step involved strategically affixing a number of large Quadratic Residue Diffusers (QRDs) on the side walls and ceiling to disperse reflected sound. "The mathematical sequence of the diffuser creates diffraction of the mid frequencies to make the room, psycho- acoustically, sound bigger than it actually is," Karni explains. "In this case, our small room felt huge!" Some of the panels were covered with acoustically transparent fabric in burgundy or muted pink to complement the plush red Moovia theater seating; others were left exposed to achieve the classic-meets-modern design Yair was going for.

Final touches to the theater include a beautiful hardwood floor with a strategically placed throw rug in the front of the room and a stretched black-fabric ceiling, designed and installed by France's Barrisol. To ensure the ultimate in comfort, the theater seats are motorized and equipped with two gold-plated cupholders.

The System
Knowing Yair wanted quick, easy access to high-quality 4K content featuring high dynamic range (HDR) and immersive Dolby Atmos sound, Nagar started with what he considered to be the "best AV solution possible:" the Pro 4K HDR media player from Paris-based Zappiti. The player was reviewed as part of a complete Zappiti system that received a Sound & Vision Top Pick in 2019.

The Zappiti feeds Sony's award winning VPL-VW760ES 4K laser projector, selected for its HDR compatibility and "superb video processing." The projector sits in a hush box built into theater's custom back wall and projects majestic images onto a 106-inch (diagonal) screen from Norway's DreamScreen. The acoustically transparent screen was chosen because it "provides the lowest attenuation available on the market, even at very high frequencies," Nagar insists.

A StormAudio ISP preamp/processor sits just below the Zappiti media player at the top of the audio chain. Chosen for its wide dynamic range, excellent room-correction software, and Dirac Live bass management, which Nagar considers to be the best, the processor feeds AES3 digital signals at 96kHz to all channels and provides immersive surround decoding for the Dolby Atmos, DTS:X Pro, and Auro-3D formats, and also has IMAX Enhanced support.

The ISP hands the signal off to five Alcons amplified loudspeaker controllers running at 4 ohms. Four Sentinel3 amps, rated to deliver 4 x 750 watts, drive three front speakers and eight surrounds, while one 4 x 2,500-watt Sentinel10 powers the system's four subwoofers. The amps were mounted in a rollable rack, hidden behind a magnetically latched door in a custom alcove on the right side of the rear wall. The door concealing the rack is soundproofed to prevent fan noise from entering the theater space. We wanted the room to be dead quiet,"

Nagar explains. To prevent heat buildup in the small cavity, Nagar's crew also installed a damped pipe that vents heat outside of the theater.

"Alcons Audio delivers a complete 'eco system' with speakers, amplification, and dedicated speaker processing," Nagar says, explaining his decision to go Alcons all the way. "The Sentinel gives you an active solution with a built-in DSP for each speaker. The filters linearize the response and avoid any anomalies the passive crossover presents while protecting the speakers to ensure maximum reliability."

Leading the suite of 15 Alcons speakers are the three CRMSCompact monitors used for the front left, center, and right channels. Each is a biamped, three-way speaker that comes in two pieces: a bass module housing a 12-inch woofer and a mid/high section that mates a 6.5-inch midrange with one of the patented pro- ribbon drivers Alcons is known for.

From there, eight compact CRMSC-SRHV speakers create the cohesive surround bubble that make this theater so special: two on the sidewalls, two on the back walls, and four firing down from the ceiling at a precise angle. Each speaker mates a 6.5-inch woofer with the same pro-ribbon driver used in the front LCRs to ensure a seamless blend between the mains and surrounds.

The surrounds were mounted higher than "textbook" position and aimed toward the seating area to achieve a greater distance to the listener, Nagar explains, adding that knowing the SRHV's exact dispersion pattern and having the ability to rotate the ribbon drivers' wave- guides was key to achieving surround-sound success.

"The Alcons pro-ribbon high-frequency drivers are amazingly fast, which translates into remarkable transient response," Nagar observes. "Combine this with almost non-existent distortion and you get a solution guaranteed to trigger emotions and create the you-are-there experience everyone is after. The dispersion pattern is also unique and evenly spread. The constant directivity up to the highest frequencies guarantees a wide and even sound field that can be easily controlled with room-correction software to achieve an in-room target response."

Four enormous CRMS-LFE18 reference subwoofers complete the speaker lineup. Two are built into the bottom of the front baffle wall and two into the custom wall at the rear of the theater—all concealed behind acoustically transparent fabric. Ready to deliver thunderous bass below 10Hz (in-room response), each LFE18 houses a beefy 18-inch woofer in a spacious 29 x 34 x 18-inch cabinet.

"Alcons speakers provide tremendous 1:15 RMS-to-peak dynamic range, which is a key for any cinema," Nagar advises. "And they do so without sounding harsh, thanks to the proprietary pro-ribbon drivers, which always operate in their 'comfort zone'—even at crazy high SPL levels."

Tiny But Mighty
When all was said and done, everyone involved with the project was thrilled with Yair's tiny but mighty apartment home theater installation. Says Karni: "We've been building recording studios and home theaters for the past 10 years and I can definitely say the Alcons CRMS system and the Storm Audio immersive AV processor in this room deliver, by far, the best theater experience I've ever heard!"

Nagar chimes in: "People get excited when magic happens and audio sounds like the real thing. It makes them smile, be excited in the moment, and forget everything else. For us, this is the most important thing."

Yair now knows with certainty that it is, indeed, possible to achieve uncompromised surround sound in a small home theater space. "The sound is so crisp, detailed, and coherent," he offers eagerly. "When you play an Atmos soundtrack, the experience becomes so vivid and precise you can pinpoint the location of every sound. It's a heavenly experience."

A/V Equipment List

• Zappiti Pro 4K HDR media server
• Sony VPL-VW760ES 4K video projector
• 106-inch (diagonal) Dreamscreen v6 acoustically transparent projection screen
• StormAudio ISP 32 preamp/processor
• Alcons Audio CRMSCompact Cinema Reference Monitor (3, front L/C/R)
• Alcons Audio CRMSC-SRHV surround speakers (8, side and height speakers)
• Alcons Audio CRMS-LFE18 subwoofers (2 in front, 2 in rear of room)
• Alcons Audio Sentinel3 (4 x 750-watt @ 4 ohms) amplified loudspeaker controller (4)
• Alcons Audio Sentinel10 (4 x 2,500-watt @ 4 ohms) amplified loudspeaker controller (1, for subwoofers)
• Amptec EtherCon digital cables
• Sommer Cable Elephant SPM440 speaker cables with Neutrik connectors
• Moovia motorized theater seats with cup holders (3)