For 25 years, THX has been a leader in bringing the best entertainment experience to the consumer, from the big screen to the home. In addition to the certification of cinemas and professional mixing studios, THX works with the major electronics manufacturers to bring consumers the best in home theatre equipment.

The company also works closely with the custom installation channel, particularly by training installers in the correct method of audio and video calibration.

THX director of education John Dahl has been a volunteer instructor for CEDIA for almost 20 years. In this time he has taught the principles of THX calibration to thousands of custom integrators from around the world.

“My goal is to teach people how to take all of their cool equipment and turn it into a home theatre,” he says.

“I want to teach them that equipment is only half the battle. How the system is set up is just as important. You can have really expensive gear but if it’s not setup properly it won’t be any good.”

John took time out of his schedule to offer the readers of Connected Home some helpful advice.

“It’s important to put loudspeakers in the right place. Rear speakers shouldn’t be aimed at the back of the audience’s head, but front speakers should be.”

“By moving chairs and furniture around you can achieve better quality bass from a subwoofer – not louder, but better quality. It will have real character to it; it won’t just be ‘bang, bang, bang’.”

“Anyone who wants to get to grips with sound design and acoustics for small rooms, you should read Sound Reproduction by Floyd E. Toole.” (Sound Reproduction can be purchased at www.tradestuff.com.au.)

“Equalisation has a bad reputation because, most of the time, the people who do it don’t know what they’re doing and they don’t have the right tools. Equalisation should be the finishing touch on a good system that is done well.”

“For video calibration, the very first thing you should do is turn off all the pre-set settings.”

“Set up a video system, and the room it’s in, in the same fashion that the end user will use it. For example, if they watch a lot of movies then turn the lights down. The contrast ratio of any display will be better if you control the room’s lights.”

“Make sure there is no light refl ecting on the screen. Manufacturers try to offer a huge dynamic range but it’s gone in a second if you don’t have good light control.”

“There should be no processing happening in the receiver. It’s the wrong place for it, unless you have particularly bad processing in the display.”

“Stop demonstrating systems with Avatar, King Kong or Mission Impossible. Everyone does that and it’s boring. It’s dead easy to create a loud system; instead, pick something with some subtlety to it. Put away the loud, obnoxious discs.”

John explains that, “unfortunately in most retail environments, salespeople simply turn a system up as loud as it can go, but after a while that just gets annoying.

“This approach also doesn’t work because people are overwhelmingly visual creatures, so audio is often swamped by video. Often when people look at a picture they will ignore the sound, unless it’s really bad.

“At THX, we’re not about being loud; we’re about creating subtlety in the space as well. And that’s difficult to do.

“Good system calibration can take several hours; it’s not a hit and run process.”