AVS member Rob M. (notnyt) is a bass aficionado. That's clear the moment you see a picture of his home-theater speaker system, which is far too massive to hide behind a screen. Rob's home theater, located in the bottom floor of his home in Mastic Beach, NY, is truly exceptional when it comes to audio fidelity.
Eight 18-inch subs in huge vented cabinets are the main attraction
A few months ago, Rob stunned the DIY-subwoofer community when he decided to switch from sealed to vented subwoofer cabinets—he felt he was leaving too much bass on the table with the sealed configuration. Furthermore, his concrete-slab foundation made it difficult to sense infrasonic sound waves, even at tremendous volume levels.
A pair of 18-inch LMS-U drivers sit on top of one of Rob's DIY vented cabinets
"This started when I first got a house about six or seven years ago," Rob recalls. "I wanted to build a theater where I could play music loud with good bass, watch movies, and play video games. It kind of became an obsession as I was never quite satisfied coming from car audio. Concrete slabs are the devil—you lose so much tactile feel. It took on a life of its own from there. After discovering AVS Forum and how crazy movie soundtracks were with a setup like this, it also became something I had to make sure was covered properly."
Despite all the power Rob's subs possess, the concrete made it difficult for him to feel infrasonic bass waves. Because he was pushing the system to its limits in order to produce a tactile response, he was concerned about damaging his LMS-U subwoofer drivers by bottoming them out.
Rob decided to build low-tuned vented cabinets to replace his sealed cabinets. The switch improved efficiency at the low end, and (crucially) provided a cushion for the drivers.
Rob's previous, sealed subwoofer cabinets
Based on what I heard during my visit, I'm confident that Rob's house will explode before his vented subs ever reach their limit. I convinced him to play "Funkenspelunkin Dub
" a track I produced specifically for elite subwoofer systems, and I swear I could see the entire house moving up and down as it played—even though it's my own track, I found myself shocked by how intense "Funkenspelunkin Dub" sounded and felt when played through Rob's system. If you are interested in trying the track for yourself, check out my The Truth Hz thread
where you'll find a uncompressed 24/96 free download of the track, but please exercise caution when playing it through powerful subwoofers.
"Funkenspelunkin Dub" really shook things up
In order to regain the feeling lost thanks to the concrete floor, Rob added Crowsen tactile transducers to his couch. At home, I have a powerful system and wooden floors that transmit vibration. When compared to my own system, deep bass from Rob's subwoofers-plus-transducer rig felt just as real; needless to say, his system possesses a lot more headroom than my own, which makes a real difference in terms of how visceral the sound effects in movies feel.
One of the two Crowsen transducers attached to the couch
Bass is the tactile cue that triggers reflexive, instinctive responses. I liken the role of deep bass in audio recordings to that of deep blacks in video or film—it is perhaps the most crucial element to achieving high fidelity that translates to suspension of disbelief. The formula is simple enough: deep bass + deep blacks + proper system calibration = goose bumps.
Rob's theater is not about fancy architecture—it's about pure performance. His theater achieves the highest levels of fidelity in a very efficient and economical manner. During my demo, we discussed numerous topics that pertain to hi-fi as a hobby, such as whether you can hear significant differences between DACs, amplifiers, and even speakers. For example, we agreed that high-end consumer audiophile equipment does not always offer as favorable a price/performance ratio as the pro-audio equipment (amplifiers and speakers) often found in commercial movie theaters.
Rob chose JBL Screen Array 4722N speakers for his left/right mains and a JBL 3677 Screen Channel speaker for his center. He uses four JBL 8350 Cinema Surround Speakers to complete his 7.2 channel rig. A Denon AVR-5308CI (which is quite a beast) provides power to the speakers; I never heard it falter during any part of the demo. A major advantage of using high-efficiency speakers in a home theater is that it typically negates the need for additional amplification—not counting the subs, of course.
Rob's high-efficiency JBL front speakers are powered by a Denon AVR-5308CI AV receiver
Bass is difficult to get just right, especially when the goal is to cover the entire audio spectrum evenly over a broad seating area. Within the audible bass spectrum, there are myriad issues to contend with, including standing-wave interactions that result in peaks and nulls. Then there is the issue of power and displacement—many subwoofers are not up to the task of playing clean and flat down to 16 Hz or so at reference levels.
Four Sanway LG FP14000 clone amps provide ample power to the subs
The best way to get quality bass in a room is to deploy multiple subwoofers. This smoothes out the overall frequency response and adds to the system's dynamic range. In Rob's case, the sheer size of the subs and quantity of drivers resulted in an extremely smooth and clean bass response. In fact, his system stood alone—it was better than the bass I heard in a Keith Yates-designed theater just a few months ago. The bass was also better than anything I heard at CEDIA 2013, CES 2014, and the New York Audio Show. The only other times I've heard anything similar to Rob's subwoofers were during visits to other AVS member's homes.
Subwoofers are not the only DIY element in Rob's system. Other such items include the corner bass traps, acoustic-treatment panels, and the screen itself. Movies are played from a custom-built HTPC featuring an 8-drive RAID-5 array. The screen—which looked fantastic—is a 115-inch (diagonal) piece of WilsonArt Designer White countertop mounted on an aluminum tube frame. To my eyes, it equaled far pricier commercial screens in terms of sharpness, color, and contrast.
In this photo you can see the projector, surround speakers, as well as DIY acoustic panels
I've spent a lot of time discussing bass, but it's worth mentioning that Rob's system is the complete package performance-wise. Once the demo began, the system drew me right into the scenes we sampled. The JVC DLA-RS10U projector produced a gorgeous image. The pod-emergence scene from War of the Worlds is one of the most intense sequences in terms of sound, and Rob's system was able to put me right into the action—it looked and felt real. I had a similar experience watching Terminator: Salvation—the tight yet powerful bass was a major contributor to the feeling of being in the movie. During the demos, I experienced the requisite goose bumps that are a side effect of true immersion on several occasions.
Rob's system triggers goose bumps, even when you are just looking at it
When I asked about power conditioning, Rob scoffed. "In my opinion, power conditioning is a joke. Voltage is converted to DC and regulated in all the electronics; it doesn't matter how precise the waveform is. Maybe if it's REALLY bad, like if you live in a third-world country or something, conditioning might be important, but not where I live."
Rob's system is the result of an evolutionary process; he built it into what it is today over the course of six years. When he first moved into his house years ago, he installed electrical wiring and hung the sheetrock needed to create a finished space, and in the process made sure that the electrical wiring he installed was heavy-duty enough to handle future needs. His primary motivation was better sound quality.
"Fortunately, as an engineer, I over-engineered the wiring in the house," he says. "I ran five different circuits into various parts of the theater area. No worries about powering monster amps. I'd get a bug up my ass for more bass or smoother response, get materials, build it ASAP, and go on from there. Construction time was years. I finished the theater area in summer of 2008 or '09. The majority of it was done over the summers, mostly on weekends, with a close friend helping, since hanging sheetrock solo is no fun."
It's a rare treat to experience a home theater like the one Rob built. It is definitive in the truest sense of the word—I have not heard a significantly better-sounding system at any price, and many systems that cost far more can’t touch the fidelity of his ultimate-bass home theater.
"It's at a point now where I'm completely happy. I have no desire for more. If anything I'd add more transducers; they were one of the best upgrades.
For much more detail about how Rob's home theater came together, check out the following threads and links:
8x 18" LMS 5400 Ultras Sealed to 27 Cube 15hz Ported Build
Lab Gruppen FP14000 clone amplifiers
Considering a new alignment for 8x LMS 5400 Ultra 18s. Thoughts?
8x 18" LMS Ultra 5400s in 4 sealed enclosures
nyt's theater / game room build
Eight 18" LMS Ultra 5400s in Four 27 ft^3 of Ported Enclosures
If you'd like your home theater considered for HT of the Month, PM Scott Wilkinson or me with the details and a link to your build thread if available.
Sony PlayStation 3
DIY HTPC with 8-bay RAID array (16 TB)
Denon AVR-5308CI AV receiver
MiniDSP 2X8 EQ
Sanway LG FP14000 power amps (4)
Behringer iNuke NU3000DSP power amp (for the tactile transducers)
DIY (WilsonArt Designer White D354-60 countertop, 115" diagonal, 16:9)
JBL 4722N (front LR)
JBL 3677 (center)
JBL 8350 (surrounds, 4)
LMS Ultra 5400 18" drivers (8) in 27 cu.ft. ported enclosures (4)
Crowson Shadow-8 Dual Motion Actuators (2)
Owens Corning 703 60"x35" DIY panels
Owens Corning 703 34" face floor-to-ceiling DIY corner bass traps
Berkline reclining sofa
La-Z-Boy recliners (2)
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