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A Home Theater Build Project - Part III

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Acoustics

Your room plays as much of a role in the way your system sounds as your equipment. However, the world of acoustics gets complicated...fast...and one can easily be swallowed up trying to understand just how sound behaves in their room and how this impacts the overall experience. Luckily, many advances in the last few years have made the process of getting our theaters sounding their best much easier.

In general, there are two ways in which one can address the way that their system sounds without actually changing equipment. We can address the room itself, whether that means room treatments or moving speakers, or we can manipulate the signal electronically, to compensate for the effects that the room is having on our system. Because my room is small, changing layout of the speakers or sub was not really practical (there were only so many options) and the random use of different acoustical treatments can do as much harm as good, so I was mostly limited to electronic manipulation of the sound to maximize what was coming from my room. That said, making sure the placement of your speakers, and especially your subwoofer, are correct is one of the easiest things you can do to begin getting great sound. There are loads written on this but my suggestion of a place to start would be the THX, Audyssey or Dolby websites.

Over the last several years the presence of auto-calibration and room correction features has become near ubiquitous in mid level receivers. Though these systems have many critics, I feel that this is unjustified. It always seems those that are quickest to point the fingers at these systems are the ones who have the technical knowledge and equipment to go far beyond what auto-calibration/room correction can accomplish. For those of use who don't have that equipment (or the budget to pay these people to come to our homes) I think the room correction features are a great way to get you closer than you'd have been without doing anything. I would counter that even with the inaccuracies, people systems sound better now then they did before such systems were so widespread. For many years I made due with these systems and the results, for me, were very satisfying and better than I had had before - so I've made sure that all of my receivers have had competent room correction/auto-calibration features. Let your ears be the final judge - if the system sounds off in someway after running auto calibration features, don't use it.

The first thing that I did to move past the basic auto calibration that a system like Audyssey was giving me was to purchase an external subwoofer equalization box from SVS. Lower frequencies are the most susceptible to negative effects from our room and the capabilities of most standard room correction features to deal with these lower frequencies is limited: enter an external sub equalization box. Units like these do essentially the same thing that the auto-calibration systems do, but are specifically targeted towards optimizing subwoofer sound. The results from the AS-EQ1 in my room were significant - not the least of which was probably due to the susceptibility of subwoofer issues in a small room. I've since moved past the use of the SVS as Audyssey's newest offering: the brand new Audyssey MultiEQXT-32, builds the functionality of the external box directly into the processing power found in my new Preamp/Processor.

Another way I moved past the basic Audyssey calibration was to purchase an Audyssey Professional Kit. Audyssey Pro brings increased functionality to standard Audyssey as well as the addition of laboratory grade, calibrated test equipment giving much more accurate measurements. Unfortunately you have to purchase a license for each unit you will do an Audyssey Pro calibration on, but the cost isn't huge ($150). Many custom installers offer this service, but Audyssey does authorize sale of the professional kit to end users, so if you think you will enjoy playing around with different type of correction curves and settings, the Audyssey Pro Kit is a great way to go.