User guide

25
Position 1 Measurement
For the Position 1 Measurement, place the microphone at the
primary (or most center) listening location. The microphone
should be positioned at ear height of a sitting listener. It is
important to have the microphone in the primary listening
position for the first measurement so that delays are
calculated correctly (see Detection Results, page 27)
Press the Measure button. The Audyssey test signal will play
a series of ten chirps through each channel. The text under
the status bar indicates which channel is currently being
measured.
After the test signal is finished playing, the application will transfer each
channel’s measurement from the DSP in the Sound Equalizer to the
computer for further processing. This takes several seconds.
Click Undo Last to erase the previous measurement.
Click Clear All to erase all of the previous position’s measurements and start
over at Position 1. The following window will appear if you click the Clear All
button.
The room measurement
process plays a series of
full-bandwidth test signals
through each channel to
measure the room’s
response. Audyssey has
designed the test signals so
that several thousand
measurement samples are
collected.
During room measurement,
some channels may repeat
the series of test signals at a
louder volume. This is done
to overcome background
noise problems and achieve
the required signal-to-noise
ratio for creating precise
room correction filters. The
level trim calculation is not
influenced by the increase in
test signal level.
The Position 1 measurement
is different from the other
position measurements that
follow. Every position
measurement measures the
room’s frequency and time
response at that particular
position. But Position 1 also
detects the absolute polarity
of each speaker, calculates
the exact acoustical
distances (within half an
inch) for setting delays, and
determines levels (within
half a dB) for each
loudspeaker. The polarity,
distance, and level from the
Position 1 Measurement are
displayed later on the
Detection Results screen
where you will manually
input the data into the
preamplifier/processor (see
page 27).
Audyssey calculates the
optimum bass crossover
frequency for each speaker.
These are often different
from the spec provided by
the manufacturer. MultEQ
Pro calculates the optimal
frequency based on all of
your position measurements
and displays it on the
Detection Results screen.
The most accurate method
of determining the correct
crossover frequency is
through room measurement.
This is because room
acoustics significantly affect
the low frequency
characteristics of
loudspeakers.
Note: The microphone tip should always point directly to the ceiling.