High Performance Home Theater Calibration

The Custom Electronics Design and Installation Association (CEDIA) was founded in 1989 in recognition of the increasing complexity of integrating audio and video systems into the home environment. Coincidently, Dolby Pro Logic was gaining solid momentum in 1989. Pro Logic was a four-channel system with five speakers; left, center, right, and two rear mono surrounds. In retrospect, the change from the previous three-channel Dolby Surround, which had no center channel, was profound. The addition of a center channel marked the first true step in the convergence of audio and video. And the founders of CEDIA recognized that a new and more complex world had emerged.

From its humble first show with vendors huddled under tents in the rains that hit the 1990 convention on Amelia Island, the founders of CEDIA envisioned an organization which offered a university-style teaching format to enable their members to stay current with the ever more complex products which would drive the custom home theater installation market.

CEDIA's mission statement reads "To educate, certify and inspire installers in the global custom electronics industry". Expanding upon this theme, CEDIA's mission statement relating to education states "To promote and expand the educational opportunities available to all levels of management and employees in the industry, in order to further the professional, business, management, technical design and installation skills of all involved in the industry."

Emerging from CEDIA's mission statement in this, their fifteenth year, are five course tracks each ultimately leading to a recognized and respected certification. The tracks are Electronics Systems Technician, Electronics Systems Customer Relations, Electronics Systems Business, Electronic Systems Project Manager and Electronic Systems Designer.

Since we at Audioholics are aware of our readers' intense interest in assembling the finest home theater or music systems, it made perfect sense that we should monitor CEDIA's courses directed specifically to setting up such systems.

Before I discuss the individual classes attended, I'd like to stress how strongly I believe in both the absolute correctness of the audio principles being taught in these CEDIA courses and in the integrity and knowledge of the instructors. To us at Audioholics, CEDIA's core courses and seminars represent the current "state-of-the-art" thinking as regards the proper design of home theater rooms, listening/viewing spaces and the equipment that goes into them. So I intend that my reports on these courses serve as a base line for correctly installed and calibrated products as we go forward with product reviews of loudspeakers and room treatments.

With CEDIA's encouragement, I chose five classes to monitor which I thought would be of most interest to our Audioholics readers. The five classes selected from the Electronic Systems Designer track were:

1. "High Performance Home Theater Calibration" taught by Anthony (Tony) Grimani
2. "Room Acoustics: Acoustics Treatment" also taught by Anthony Grimani
3. "Acoustics 101" taught by John Dahl
4. "Room Acoustics: Isolation and Noise Control" taught by Steve Haas
5. "Room Acoustics: The Room and Loudspeaker System" taught by Dr. Floyd Toole

At the conclusion of these five seminars I came out with one outstanding paradigm which was echoed by each of the presenters. That is, a signal from the airwaves or through some form of recorded media passes through all the associated wiring and electronics. It emerges from the speakers and travels through the air to your ears at your listening position. The sound of that signal at your ears is 50% the direct sound from the speakers and 50% the sound generated by the room.

That bears repeating: The sound of that signal at your ears is 50% the direct sound from the speakers and 50% the sound generated by the room.

Since this assumption leaves out the associated electronics it will be our stance at Audioholics to add that cost back in a more representative proportion. Therefore, the cost of a dollar-wise- efficient system geared toward maximum bang-for-the-buck performance will be allocated thusly; 20% for all electronics, 40% for all loudspeakers and 40% for the room and the treatment to the room that will allow the loudspeakers and electronics to function optimally.

I'll address these ratios in another Audioholics column in the near future. For now though here's an overview of what the installation professionals learned in the first of the Electronics Systems Designer level 300 and 400 courses I attended: