Re-Equalization™
Timbre Matching™
Adaptive Decorrelation™
Advanced Speaker Array™
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The tonal balance of a standard film soundtrack will be excessively bright and harsh when played back over high quality audio equipment in the home because film soundtracks were designed to be played back in large movie theatres using very different professional equipment.
The human ear alters our perception of a sound based on the direction from which the sound is coming. Thus two identical sounds arriving from different directions sound somewhat different to us (based on the asymmetrical shape of our ears). In film soundtracks, this can introduce discontinuity as sounds pan from the front to the rear of the room, even if the speakers themselves are quite
The Timbre Matching feature filters the information going to the surround speakers so that they more closely match the tonal characteristics of the sound coming from the front speakers. This ensures seamless panning between the front and surround speakers.
In a movie theater, there is an array of perhaps a dozen surround speakers so that the surround information is literally all around you. This creates a diffuse surround soundfield that envelopes you, drawing you into the action on the screen rather than distracting you from it.
By contrast, in a home theater you often use only two speakers, located to the sides and somewhat behind you. Even in more elaborate “7.1 channel” systems, you still have only two speakers to the sides and two speakers to the rear – quite different than the surround array for which the soundtrack was mixed. This difference can make the surround speakers sound like headphones, lacking spaciousness and envelopment. The surround soundfield also tends to collapse into the closest speaker as you move away from the middle seating position.
Adaptive Decorrelation™ – another THX technology – slightly changes each surround channel’s time and phase relationship with respect to the other surround channels. This expands the listening position and helps create – even with only two surround speakers – the same spacious surround experience as in a movie theater.
The people at THX have also found a solution to a problem that dogged high performance multichannel systems for years: the apparent conflict between optimal music and movie setups.
You see, movies are mixed in highly standardized environments, with even spaced surround speakers in an array designed to provide a diffuse, enveloping soundfield. Their goal is to draw you into the movie on the screen. If the surround sound tempts you to look over your shoulder, the system has failed: it has reminded you that you are safe in your living room rather than “in” the movie you are watching.
