Parasound AVC-2500 - Manual (Page 30)

30
THX Cinema
By pressing the THX button on the remote control or on the front panel, you can activate the
advanced Home THX Ultra enhancements listed below. The AVC-2500 is among the very
few AV Controllers designed and qualified for THX Ultra Certification. Films that have
been encoded in Dolby Digital, DTS, Dolby Pro Logic, Stereo or even Mono can all benefit
from activating THX Ultra technologies. THX should be selected when watching movies
that were mixed primarily for playback in large movie theater environments in which speakers
are always mounted behind the screen. THX engineers developed patented technologies to
accurately translate the sound from the movie theater environment into the home, correcting
for significant tonal and spatial discrepancies between these environments. When the THX
mode is selected on the AVC-2500, the decoded signal is modified with the following THX
Ultra features:
THX Re-Equalization
The tonal balance of a film soundtrack may be excessively bright and harsh when played
back over audio equipment in the home because film soundtracks were designed to be played
back in large movie theaters using very different professional equipment. Re-Equalization
restores the correct tonal balance of a film soundtrack in a small home environment.
THX Timbre Matching
The human ear changes our perception of a sound depending on the direction from which
the sound is coming. Large movie theaters must use arrays of speakers to provide surround
information for everyone in the audience. In a home theater, you need only two surround
speakers located at the sides of your head. 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 and an uninterrupted sense of spaciousness.
THX Adaptive Decorrelation
In a movie theater, there is always a large distance from your seat to the speakers. In a home
theater there are usually only two surround speakers that are usually located close to your
listening position. Adaptive Decorrelation slightly changes one surround channel’s time and
phase relationship with respect to the other surround channel. This has the effect of expanding
the apparent size of your room and broadens your listening position to simulate the same
spacious surround experience as in a movie theater, but with only two surround speakers.
THX Bass Limiter
This THX feature prevents distortion and possible damage to the woofers in your speakers
or subwoofer. Details about the Bass Limiter are in the Setup section.
Music Mode
Dolby Digital
While in the Music ASP mode, the AVC-2500 automatically decodes Dolby Digital encoded
source material. If the material was encoded in Dolby Digital 5.1, the AVC-2500 plays back
all six channels independently. If the material was encoded in Dolby Digital 3/1 or 2/0, the
AVC-2500 downmixes the signal to Pro Logic Surround.
DTS
In the Music ASP mode, the AVC-2500 automatically decodes DTS encoded source material.
Since DTS is always encoded in 5.1, the AVC-2500 will play back all six channels while in
the Music mode. Choose this mode for DTS music discs. Choosing the Music mode for
DTS movies is not recommended because bass response may be attenuated.