My Engineering Masterpiece

Nine years ago, my wife and I had our home custom-built on an isolated 11-acre lot. The theater room continues to evolve into the vision I had back then. I wouldn’t say that it’s entirely completed, but it’s definitely fully functional and a pleasure to use and entertain in.

I am a hard-core DIY-er, but I do occasionally need help. My wife helped pull all the low-voltage wires for the phones, computer network, house audio/video, speaker system, and satellite dish as the house was under construction. We installed a couple of 2-inch electrical conduits from the basement to the attic, one for the stage lighting truss (more on that later) and one for future wiring needs. I worked with the architect to change the theater room dimensions to improve the acoustics and make space for all of the equipment.

I have worked for Bosch Security Systems for 25 years as an engineer designing motion detectors, and have a security system that the Department of Defense wishes they had. There are five video cameras, 15 motion detectors, and outdoor photo beams. Some are engineering prototypes that aren’t available to even Uncle Sam yet. I could say more, but then I would have to kill you.

The stereo system in my home theater room is totally separate from the 5.1-channel system I use for watching movies. The stereo system has evolved over the years as I continually modify and update it. Currently, all of my music is loaded onto a 500-gigabyte hard drive in the HTPC I built. All of the audio signals are processed in the digital domain until the last possible stage. The D/A conversion is performed in the six-channel digital crossovers, just before the power amplifiers. The digital crossovers allow me to time-align the horn drivers of the Klipsch La Scala speakers. This produces a stereo image that will startle you. The total power amounts to around 2,000 watts per channel. I have meticulously combed through each audio component looking for opportunities to make improvements to the sound quality. This usually means upgrading the op-amps and capacitors in the signal path.

I run the theater system using a 61-inch HD monitor for everyday TV viewing or the 133-inch projection screen for movies. The center speaker is flush-mounted behind the acoustically transparent screen. When I first got my speakers, all three front speakers were Klipsch RC3 models. I selected them because they are very efficient, and I easily made new sealed enclosures that I mounted in the walls. I maintained the original box volume and stuffing, and the results were fantastic. Each of the 5.1 surround speakers uses a separate amplifier. I modified the JVC surround receiver by hacking in my own balanced preamp output circuit for all six channels. This allows me to connect to the amplifiers for more power, which is needed for the large room. I disabled the power amplifier stages within the JVC to reduce the heat it generates, even when it’s idling.

I made some of the room furnishings myself. I sewed the large theater-style curtains using material from Rose Brand, a theatrical fabric supplier. I received help, instructions, and encouragement from a family seamstress for this because the only sewing experience I had was making parachutes for my rocket-photography hobby, but that’s another story. I designed and built the motorized curtain system using motors and parts from my local electronics surplus store. My universal remote can open and close them, of course. I constructed the larger center coffee table using half electrical conduit bent and welded to match the smaller end tables. I put together the rear-seating platform last year, again with help from my wife. She wrestled the carpet around the curved corners while I stapled it.

I designed, fabricated, and welded the lighting truss in the garage of my old house while the new house was under construction. The scary part was hoisting it up 17 feet on a pulley system as images of it swinging through the large picture windows danced in my head. For this task, I needed help from both my wife and my brother. The lights can all be controlled and dimmed individually using my universal remote control. The projector hush box is also mounted on the truss. The projector screen retracts into the soffit. My wife doesn’t like to climb ladders, so I had to use a pulley system, which she pulled on while I screwed everything down as I stretched from the ladder. We also have a homemade green laser interference pattern generator. The pattern changes imperceptibly slowly to keep it interesting as the hours pass by.

We’ve gotten a lot of use out of our theater room and there is a lot of personal satisfaction and pride that we did most the work ourselves. I enjoy working on it so much I hope it is never “complete.”

Equipment list:
Behringer Super-X Pro CX3400, Four-Way Crossover
Toshiba HD-A2 HD DVD Player
Optima HD81 1080p Home Theater Projector
JVC RX-D412B Audio/Video Receiver
Audio Control C-50A Spectrum Analyzer
Behringer Ultradrive Pro DCX2496 Loudspeaker-Management System (2)
Behringer Ultracurve Pro DEQ2496 Digital Audio Processor
Behringer EX1200 Bass-Management System
Hafler Transnova P3000 400-Watt Power Amplifier (3)
Crown K1 Balanced Current Power Amplifiers, 350 Watts/Channel (3)
Crown K2 Balanced Current Power Amplifier, 500 Watts/Channel
Home Theater PC (Custom-Built Pentium D 3.0-GHz CPU, 500-GB Hard Drive, 3 GB RAM)
E-MU 1820M Digital Audio Interface
Hafler P2400 Power Amplifier
Da-Lite Tensioned Cosmopolitan Electrol 133-Inch Audio Vision Projection Screen
Sony KP-61HS10 61-Inch Rear-Projection TV
Klipsch La Scala Floorstanding Loudspeaker (2)
Klipsch RC-3 Reference Series Loudspeaker (3)
Dayton Titanic Mk III 12-Inch Subwoofer
Dayton Titanic Mk III 15-Inch Subwoofer
Fortress 750 UPS
Tripp-Lite LC2400 Line Conditioner
Equipment Rack/Roadcases, Hand-Built (2)