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In the basic
ALL
procedure as described earlier, a system is captured exactly as it is, with a full
set of real speakers being emulated as virtual speakers. All the channels are switched on at the
start, all are switched on for saving at the end, and
SAVE AT END
is set to
YES
at the
outset.
In addition, a very useful aspect of the
ALL
procedure is that one can create additional channels
and speaker placements by measuring one or more speakers in certain positions and then
moving the speaker or speakers to other positions for additional measurements. A real stereo
pair can become a virtual set of five or seven; a single subwoofer can become a pair, etc.
The measurements are made in stages. Set
SAVE AT END
to
NO
at the outset. Press
CAL
and turn on only the channel or channels to be measured in the first round, which must always
include Channel 1. Run the level calibration. Press
SPK
and verify that the same channel or
channels are turned on, and run the sweeps.
Next move the speaker or speakers to the next desired locations and repeat the
CAL
and
SPK
procedures. There can be as many stages as you wish; run both
CAL
and
SPK
each time.
Before the final stage, set
SAVE AT END
to
YES
. (If you forget to set
SAVE AT END
to
YES
before the final round, simply set it to
YES
and run one of the sweeps again, but
not
channel 1.)
Running
CAL
on channel 1 erases the
CAL
values on all other channels, so it must always be run
on the first round and never on subsequent rounds.
After the final sweep and the diagnostic screens, the channel on/off screen reappears. This
screen sets which channels are saved into the PRIR. Switch all channels
ON
which have been
measured in all the stages combined. Finally
ID
and
EV
are entered as described earlier and the
PRIR is saved.
The
ALL
procedure, when run in stages, is the most flexible way to multiply speakers. There
are two other procedures which streamline the process of creating multiple speakers from a
single speaker, and for creating 5- and 7-channel arrays from a stereo pair.
ONE
-- In this method, a single real speaker is used to generate eight virtual speakers at regular
spacings.
The procedure begins with the listener looking directly at the speaker (0° or 12 o’clock) for the
first sweep, then rotating clockwise to +30° (1 o’clock) for the next sweep, and so on through
twelve measurements, one for each 30° increment or one for each hour on the clock. One might
use a low-back rotating office chair to facilitate moving among the positions.
The resulting virtual speakers will be the following, at the positions given.
Left
-30°
Centre
0°
Right
+30°
Left surround
-90°
Right surround
+90°
Left back
-150°
Right back
+150°
“Subwoofer”
180°
The “subwoofer” measurement is of course not a subwoofer but the same speaker as is
measured for all the other locations. Being assigned as
SW
means that the incoming subwoofer
channel will map to it. If a real subwoofer is available, one will want to do a second
