Operation Manual

The Advanced MCACC menu
10
84
En
How to interpret the graphical output
The graph shows decibels on the vertical axis and time (in
milliseconds) on the horizontal axis. A straight line
indicates a flat-response room (no reverb), whereas a
sloping line indicates the presence of reverberation when
outputting test tones. The sloping line will eventually
flatten out when the reverberant sound stabilizes (this
usually takes about 100 ms or so).
By analyzing the graph, you should be able to see how
your room is responding to cer tain frequencies.
Differences in channel level and speaker distance are
taken into account automatically (compensation is
provided for comparison purposes), and the frequency
measurements can be examined both with and without
the equalization performed by t
h
is receiver.
1
Setting Acoustic Calibration EQ Professional
according to your room characteristics
Using the manual setup, you can set the time period at
which the frequency response is analyzed, pinpointing
the time that is best for system calibration with your
particular room characteristics.
The graph below shows the difference between
conventional acoustic calibration and professional
calibration (the gray circle indicates the point where the
microphone cap tures sound during frequency analysis).
As soon as audio is output from your speaker system, it
is influenced by room characteristics, such as walls,
furniture, and the dimensions of the room. The sooner
the frequency a
nalysis, the less it
is influenced by the
room. We recommend an earlier time setting of 30-50ms
to compensate for two major factors that will influence
the sound of most rooms:
• Reverberance of high vs. low frequencies –
Depending on your room, you may find that lower
frequencies seem overly reverberant compared to
higher frequencies (i.e. your room sounds ‘boomy’).
This may result in a skewed frequency analysis if the
measurement is done too late.
• Reverb characteristics for different channels –
Reverb characteristics can be somewhat different for
each channel. Since this difference increases as the
sound is influenced by the various room
characteristics, it is often better to capture a
frequency an
aly
sis early on for smoother mixing of
channel frequencies/sounds.
If your room isn’t affected by the factors above, it is often
not necessary to make a 30-50ms setting. Later time
settings may provide a more detailed sound experience
with your speaker system. It is best to try and see what
works best for your particular room.
Note that changing the room (for example, moving
furniture or paintings) will affect the calibration results.
In such cases, you should recalibrate your system.
Using Acoustic Calibration EQ Professional
1 Select ‘ EQ Professional ’, then press ENTER .
Note
1 Note that due to an effect known as ‘group delay’, lower frequencies will take longer to be generated than higher frequencies (this is most
obvious when comparing the frequencies at 0 ms). This initial slope is not a problem (i.e. excessive reverb) with your listening room.
Level
Test tone
Acoustic Cal. EQ Pro.
calibration range
Conventional MCACC
EQ calibration range
Time
(in msec)
80
160
0
Level
Low
frequencies
Acoustic Cal. EQ Pro.
calibration range
Time
(in msec)
80 160
High
frequencies
Conventional MCACC
EQ calibration range
0
Level
Front L
Acoustic Cal. EQ Pro.
calibration range
Time
(in msec)
80 160
Front R
Conventional MCACC
EQ calibration range
0
1. Fine Channel Level
2. Fine SP Distance
3. Standing Wave
1c.Manual MCACC
4. EQ Adjust
5. EQ Professional
A/V RECEIVER
Exit Return
a. Reverb Measurement
b. Reverb View
c. Advanced EQ Setup
1c5.EQ Professional
A/V RECEIVER
Exit Return
VSX-9140TXH_CUXJ.book 84 ページ ２００９年４月１６日 木曜日 午前１０時３６分