Read Sharp 76GF-64H (serv.man10) User Guide / Operation Manual online
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About DOLBY PRO LOGIC
Dolby Surround decoders are designed to work together with specially encoded audio soundtracks (Dolby Stereo
movies or Dolby Surround video productions) to provide a front-to-back soundfield dimension which complements
the left-to-right dimension of conventional stereo. Pro Logic decoders use directional enhancement techniques and
additional centre channel output to improve soundfield localization over a wider viewing area. A major benefit of
active decoding through left, centre, and right speakers is the ability to link sound with the picture as well as to
provide full stereo dimensionality when appropriate, and to provide this improvement over a wide viewing area.
Therefore, the capabilities of active decoding are best achieved when the left and right speakers are positioned
widely enough to obtain a good stereo effect. Note that the movies are mixed with the front speakers placed to cover
approximatelly a 50 degree angle ahead of the viewer, so reducing this angle for home reproduction will
proportionally narrow the intended soundfield. The Pro Logic decoding provides surround channel output, but their
potential also extends to the improved frontal soundstaging capabilities. In order for this to be achieved in the home
it is necessary to use left, centre, and right speakers in their proper positions. The preferred configuration for
television system would be to include the centre speakers within the receiver, and provide stand-alone speakers for
the left and right channels.
movies or Dolby Surround video productions) to provide a front-to-back soundfield dimension which complements
the left-to-right dimension of conventional stereo. Pro Logic decoders use directional enhancement techniques and
additional centre channel output to improve soundfield localization over a wider viewing area. A major benefit of
active decoding through left, centre, and right speakers is the ability to link sound with the picture as well as to
provide full stereo dimensionality when appropriate, and to provide this improvement over a wide viewing area.
Therefore, the capabilities of active decoding are best achieved when the left and right speakers are positioned
widely enough to obtain a good stereo effect. Note that the movies are mixed with the front speakers placed to cover
approximatelly a 50 degree angle ahead of the viewer, so reducing this angle for home reproduction will
proportionally narrow the intended soundfield. The Pro Logic decoding provides surround channel output, but their
potential also extends to the improved frontal soundstaging capabilities. In order for this to be achieved in the home
it is necessary to use left, centre, and right speakers in their proper positions. The preferred configuration for
television system would be to include the centre speakers within the receiver, and provide stand-alone speakers for
the left and right channels.
About Automatic volume correction
Different sound sources, fairly often do not have the same volume level, for example the changing from movie to
the advertisements. The Automatic Volume Correction (AVC) solves this problem and equalizes the volume levels.
the advertisements. The Automatic Volume Correction (AVC) solves this problem and equalizes the volume levels.
About Pro Logic Mode
The Dolby Surround Pro Logic effect enables the consumer to chose from a variety of possible modes:
Normal: The centre channel response is limited to 100 Hz and above, and to prevent any apparent loss of bass,
the bass content of the centre signal is redirected to the left and right outputs. This bass splitting process is a
required feature in this mode.
the bass content of the centre signal is redirected to the left and right outputs. This bass splitting process is a
required feature in this mode.
Wide: In this mode the bass splitting process is not present and the centre channel response is not limited.
Phantom: The phantom mode simulates a centre channel by splitting the centre channel information equally
between the left and right speakers.
between the left and right speakers.
3 Stereo: The three channel mode or Dolby 3 Stereo mode is a subset of the Pro Logic. In this mode the surround
output is muted and directional enhancement for surround signal is disabled. One purpose of this mode is to provide
good system performance until surround speakers are in place. The other purpose is for playback of heavily
synthesized stereo programs which create wide but diffused sound images that become distracting when
reproduced through a full surround system.
It’s recommended to complete the system and switch to the normal mode as soon as possible in order to benefit
from the full spatial capabilities of the system.
output is muted and directional enhancement for surround signal is disabled. One purpose of this mode is to provide
good system performance until surround speakers are in place. The other purpose is for playback of heavily
synthesized stereo programs which create wide but diffused sound images that become distracting when
reproduced through a full surround system.
It’s recommended to complete the system and switch to the normal mode as soon as possible in order to benefit
from the full spatial capabilities of the system.
About Surround delay
In order to reduce the perception of leakage signals from surround speakers, the decoder must compensate for the
travel time of sound through air, which is approximately one foot per millisecond. By knowing the distance from the
listening position to the front and surround speakers, it is then possible to adjust the time delay to obtain the desired
results. A delay time of 20 milliseconds is required, but, for improved tailoring of the system, the delay may be
adjustable from 15 to 30 milliseconds in several steps. A variable time delay allows greater flexibility and improved
control of arrival time.
travel time of sound through air, which is approximately one foot per millisecond. By knowing the distance from the
listening position to the front and surround speakers, it is then possible to adjust the time delay to obtain the desired
results. A delay time of 20 milliseconds is required, but, for improved tailoring of the system, the delay may be
adjustable from 15 to 30 milliseconds in several steps. A variable time delay allows greater flexibility and improved
control of arrival time.
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