Audyssey Auto Calibration - NAD T 785 Owner's Manual

OPERATION
USING THE T 785 – SETUP MENU

AUDYSSEY AUTO CALIBRATION

It has been shown that many, if not most, surround sound systems are not
accurately setup and calibrated. To be done properly, calibration requires
special knowledge and instrumentation that the average person probably
doesn't possess.
The Audyssey Auto Setup and Calibration featured in T 785 uses a
microphone, along with sophisticated digital electronics built into your
T 785, to automatically setup and calibrate the T 785 to the exact speakers
and speaker placement of your own unique Home Theatre.
The following measurements are performed:
• Detection : Speaker configuration is detected including number of
surround speakers and whether a subwoofer and center channel is
connected.
• Size : T 785 crossover is set based on each channel's signal handling
capability and the subwoofer crossover is automatically set.
• Level : SPL of each speaker is matched within 1dB at the microphone
position.
• Distance : is accurately set to within 1 foot (30 centimeters) of the
microphone for each speaker position.
• Polarity : the setup program will detect and notify the user if any
speakers are connected improperly. Incorrect polarity can ruin the
illusion of realism offered by surround sound.
This is a one-time set up, unless speakers are moved or changed, in which
case the calibration should be performed again.
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AUDYSSEY MultEQ XT ROOM ACOUSTICS CORRECTION
Sound reflecting from room boundaries can disturb the spatial illusion
of surround sound, and can also distort the tonal balance of the system.
Professional Acoustical Engineers often add wall treatments and even move
walls and relocate speakers to improve system performance, but for the
average Home Theatre, this is either too expensive or just not a practical
solution.
Audyssey MultEQ XT, using multiple measurements from the actual
listening positions, and processing this information using very sophisticated
digital signal processing, is able to "precondition" the signal to effectively
make the walls disappear. This creates a 'family size' sweet spot where the
sound and spatial cues are very accurately reproduced.
MultEQ XT is designed to tame room acoustics without changing the sonic
character of your loudspeakers. While it will make the most of whatever
loudspeakers you have, it will not make poor speakers sound like good
ones!
Connect the Audyssey microphone jack into the front panel's MP/MIC input
and the Audyssey Auto Calibration wizard will guide you through a simple
step-by-step configuration. Once setup and calibrated, the next greatest
improvement in performance is obtained by eliminating the acoustic
interference caused by room boundaries interacting with your speakers.
MEASUREMENT IS THE FIRST STEP
The sound at each listening position (up to 8 positions) is calibrated using
the same microphone used during the setup phase.
A special test tone is sent to each speaker and the data is memorized by
the T 785. The duration of calibration may take some time depending on
the number of speakers as well as the number of measuring points. After
all positions are measured, the DSP calculates the ideal system response for
your particular room and speaker setup.
If some inconsistencies or discrepancies are detected during the Audyssey
calibration, the process maybe interrupted or the problem is shown in the
particular setup window. A notice screen is correspondingly displayed.
After following and undertaking the displayed instructions, re-start the
Audyssey calibration again. When the measurements are finalized, Audyssey
calculates the ideal system response for your particular room and speaker
setup.
NOTE
The test tone emitted during measurement is loud. This maybe
bothersome for you and may affect your other household members as
well, and even your neighbor.