Thursday, September 22, 2016

A Techie's Dream Cinema - CEDIA 2016 Design Awards Winner

The life of an audiophile is driven by a relentless and unending pursuit of the idealized audio experience and the feeling of being transported to concert venues all over the world at the hit of the Play button. Sometimes this hobby also consumes the family living quarters and clutters them with large equipment, unsightly wiring, and seating arrangements that aren’t conducive to afternoon tea.
A living room in a luxurious Tuscan-style Southern California home was to be converted into a dedicated listening room and home cinema for an uncompromising audiophile client. It houses a concealed set of large Wisdom Audio LS4 speakers, matches the classical interiors of the residence, and serves as a soundproofed retreat. Exceptional picture quality with 4k UHD resolution and 2.35:1 projection screen, Dolby Atmos immersive audio playback, and fully integrated automation for access to the extensive collection of jazz, classical, and rock music, complement the stellar audio-video package.
Our client tried on his own to reach his dreams of audio excellence, swapping out several brands and models of speakers and amps, adding in tuning accessories, ultra-premium cabling, acoustical modules, changing rooms, and eventually throwing his hands up. When he reached out to our team, it was clear that he wanted it all: top-of-the-line audiophile sound; fully concealed loudspeakers that would give him back the beautiful ocean view from his living room window and the rustic Italian d├ęcor that permeates the whole residence; integrated and simple control; home theater functions with UHD video and Atmos immersive sound.
Our mission was to design and engineer an environment that could support and enhance the very sophisticated audiophile audio system, and instantly switch to movie studio-grade AV performance. The client wanted to spend a lot of time enjoying his passion for music and films, so the interior feel had to be comfortable and warm.
The project started with extensive engineering and planning six months before construction until all elements were carefully thought through. First off, the room itself was engineered for the right sound isolation and for interior acoustical sound reflection optimization. The room was closed off from the dining area with a resilient staggered stud sound isolation wall structure in the original archway. A front soffit system was built into the coffered ceiling in order to conceal the motorized screen and ductwork. We established the idealized speaker locations using computer modeling during the engineering phase and confirmed the locations of the front speakers and subwoofer with in-situ testing.
The theater was built as a remodel of this one wing of the home, and we had to do a lot of discovery and demolition to determine all the design and engineering parameters and specifications. Pre-wire from the equipment room to all the speakers had to include control of sound isolation leaks, vibration and rattles, and timing logistics. The project required some creative thinking from all in the team to figure out how to incorporate the drop down screen, conceal all the speakers, and apply acoustical tuning where there wasn’t stretched fabric. The front and back sections of the coffered ceiling were re-dimensioned so as to incorporate the screen mechanisms. A wideband absorber placed in front of the fireplace hearth is in fact dressed up as a fire screen. Artwork over the fireplace is in fact a LivingSound absorber module with custom artwork printing.
Aesthetic integration created the usual challenges for speaker placements, acoustical materials placements, etc. But the largest issue in this project was that the orientation of the room prevented easy integration of a Center speaker. The client wanted to be able to look out at the view at the front of the room between the Left and Right speakers, when listening to music. Also, the client picked a very large and effective speaker system, and concealing was tricky. We formulated the idea of recessing the L/R speakers in coves carved into the wall structures lateral to the large sliding glass doors. With proper baffling, acoustical damping of the cove surfaces, and carful tuning, we were able to achieve audiophile sound out of the pair of speakers, despite their location. Also, we were able to achieve a soundstage with a solid phantom center sound character and wide enough sweet spot, so as to forego the use of a Center speaker. We did prewire for a motorized unit in case it is decided to add it in per the plans.
The engineering team then specified a Dolby Atmos 6.4.2 speaker package, with large planar array LR speakers concealed behind stretched fabric coves flanking the acoustically transparent screen. The surround array consists of matched Side speakers along the lateral walls, two matching Back speakers, and four matching Top speakers to complete the immersive effect. Four highly efficient yet compact subwoofers were laid out in the Welti "four corner” configuration for smoothest response and maximum gain.
The display system features a 4K projector along with an acoustically transparent 2.35:1 screen. The projector was picked for appropriate light output and picture quality. The speaker package features a pair of large planar magnetic Wisdom Audio LS4 speakers, carefully integrated into acoustically damped coves and toed in for best imaging results. The speaker coves were essentially “carved out” of the false walls originally built out for the sliding section patio door system. We blocked out a portion of the slider travel limits, and appropriated the resulting space for the L/R speaker coves. A drop-down center speaker was planned into the design, and it was agreed that the client would first evaluate if he was happy enough with the phantom center character of the Wisdom LS4 speaker pair.
A Dimension4 Sonata acoustical tuning package was engineered, with the goal of achieving a target reflection decay time of 0.3 seconds across the audio spectrum - including appropriate 2D and 3D diffusion in the 500 Hz to  5 kHz region.
In this industry we often cater to clients that want nice audio and video, and understand the value of hiring a boutique operation. However, they don’t often have a reference of what is high performance sound or picture. So it is a thrill to work for real enthusiasts, and watch them be amazed at results that are so far beyond what they had ever expected.

The client now has a home cinema and audiophile listening room that rivals the best in the world and spends several hours a week enjoying it. He was so happy with the outcome, that he invited us to stay for an enjoyable evening of music listening paired with fine wines. Yum!

Tuesday, September 20, 2016

Dedicated High Performance -- CEDIA 2016 Design Awards Winner

In this industry, we regularly cater to “enthusiast” clients who are very enthralled with the idea of a fully engineered and commissioned private cinema. They may have played with speakers and receivers in their spare time. They may have preconceived notions about what makes speakers work or not work. They may even want to tell the crew how to go about doing the wiring and installation.
This client just built his Tuscan dream home in the rolling hills over Newport Beach, California. He wanted a great place to enjoy concert videos and movies from all around the world. He got that and a lot more in an acoustically treated and tuned room with appropriate sound isolation, Dolby Atmos immersive audio, 4K video, and a luxury-grade interior finish.
The room was to be laid out as a formal dedicated two-row theater, without many design frills, and with maximized return on investment for the equipment. The client decided not to adopt the customary stretched fabric dress in order to put more money into engineering, gear, and installation quality. In other words, budgets were very tightly controlled. There was no room for error in the engineering and commissioning.

Interior design was conspicuously absent. The client decided to focus all the available funds on engineering, equipment, and installation, so he did not budget in a stretched fabric wall decorative system. Since the room had an acoustical treatment package, we paid attention to laying out the absorbers and diffusers in a relatively even and consistent pattern, while preserving an optimal acoustical tuning balance. The walls, along with all the acoustical materials and speakers, are all flat black so as to disappear from view once the lights are dimmed.
Since the client is a techie, it was only appropriate to give him the latest technologies. The room had to have a very large 4K display and immersive audio for Dolby Atmos playback. First off, the room itself was engineered for the right sound isolation and for interior acoustical sound reflection optimization. The engineering team then specked in a Dolby Atmos 9.4.4 speaker package, with matched LCR speakers behind the huge acoustically transparent screen, Atmos Wide speakers brand-matched to the LCRs, dual Side speakers along the lateral walls, two matching Back speakers, and four matching Top speakers to complete the immersive effect. Four highly efficient yet compact subwoofers laid out in the Welti "four corner” configuration were selected to belt out the bottom octaves at the requisite peak sound pressure levels.
The picture end of the design was to present an image large enough to fully express what today's 4K Ultra HD video is meant to show, while not breaking the bank with a Digital Cinema-grade projection engine. Through careful matching of the screen gain, along with very dark colors in the room, we were able to achieve the maximum contrast ratio in that room - along with deepest blacks and satisfying peak white levels. The display system features a 4K projector along with an acoustically transparent 2.37:1 screen. The projector was picked for appropriate light output and picture quality. The screen was carefully evaluated for acoustical and optical performance so as not to lose any sonic or visual quality.
The speaker package features a matched set of Triad speakers. The Triad InWall Gold LCR speakers up front were baffle-mounted for better control of the bass response. The Wide channels in the Dolby Atmos format are handled by a pair of Triad InWall Silver LCR speakers, appropriately aimed back to the seating area for best coverage. The Side and Back channels are all handled by custom bipole Triad OnWall Bronze Surround speakers for best spatial integration and envelopment. The Top channels are handled by custom bipole Triad OnWall Silver Surround speakers for best coverage and immersion. The bottom octaves are handled by a set of four Triad InWall Bronze/6 subwoofers arrayed in the four corners of the ceiling for best balance between standing wave performance and room gain. They were resiliently mounted on rubber bushings in order to reduce sound transmission and rattles.
A Dimension4 acoustical tuning package was engineered with the goal of achieving a target reflection decay time of 0.3 seconds across the audio spectrum - including appropriate 2D and 3D diffusion in the 500 Hz to 5 kHz region. All the speakers were optimized through 15-band digital parametric equalization, carefully and lovingly tuned and voiced by a professional audio engineer - using a combination of impulse response measurements with spatial averaging, time varying windowing, and psychoacoustic smoothing.

In the end - after much patience and collaboration - it's a real thrill to witness the client's amazement at results that are so far beyond what they had ever experienced or expected. We spent several hours listening through every part of the Dolby Atmos demo disc, along with several of our favorite Blu-ray Disc demo sections. This project shows that - with careful engineering, equipment selection, optimized installation, and calibration - you can realize the full potential of the client's investment and produce a very exciting cinematic experience on a modest budget.

Friday, July 29, 2016

The Mysterious Case of the Turntable Hum

So there's this project down in SoCal; the client is a huge vinyl rock 'n roll and blues fan with what you'd call a multi-use media room. After the initial commissioning of his system, everything was groovy (pun intended) save for some serious hum and noise issues with the high-end turntable rig. Unfortunately, scheduling required us to knock off before we could track down all the issues. 
Over the next while, the installer's guys and some outside consultants gave it their best shot - to no avail. Eventually, I said, "Enough is enough; we've got to get this guy squared away."  

So, I loaded up my test gear, tossed in my trusty Technics SL1200 turntable with a basic preamp of my own, and headed south.
After a good bit of head banging (the bad kind) and hair-pulling, I replaced his turntable and phono pre with mine. Presto! Hum/noise gone. Taking systematic approach of slowly inserting the client’s gear into the scheme, I found a “perfect storm” of issues that caused the unacceptable levels of hum and buzz.
First off, a (much) closer look at his turntable revealed that the connector box that took the cartridge lead-in wires to the RCA connectors was powder-coated. Uh-oh. The ground lug, barrel connector for the lead-in, and the RCA connectors were all touching a powder coat finish instead of actual metal, and there was no ground contact anywhere. So there I was for an hour scraping off powder coat from the contact points with a tiny screwdriver. Good times! A reasonable person would expect that to fully fix all the issues, but no such luck. 
I then observed that the lead-in wire that looped up and out of the tone arm wasn't shielded and picked up RF interference. Also, we still had some oscillation and hum with his phono pre, but not mine. It was a vacuum tube device; lo and behold, one of the tubes was probably bad! We replaced the preamp with a fresh one from stock, thanks to some forward thinking on the part of the installer. Better, but still not perfect.
That's when I noticed the single-ended link between the phono preamp and the main pre-processor - a distance of about 25 feet - ran near lights and other EMI/RFI-spewing electronics. I don't want to point fingers, but that's kind of a no-no. Such a run needs to be balanced in order to reject the noise. Luckily, the wire used for the connection was actually a twisted pair with shield. So we upgraded the connection by inserting a Jensen transformer-based balanced converter after his phono pre and running the other end of the wires into a set of XLR balanced stereo inputs of the main system pre-processor.
There was still a tiny bit of noise audible when listening at a few inches from the tweeters, attributable to the non-shielded lead-in wire and noise floor of the tube-based phono preamp. The shield issue is simple enough to fix with a very flexible braided shield connected to the main ground lug. The quiescent phono stage noise floor is then probably low enough not ever be heard at the seating position.
The end result was a great improvement in the hum/noise problem - also some renewed lessons learned about verifying that gear actually comes from the factory working right!