97
Bass redirection within the Realiser
The Realiser has the ability to accomplish bass redirection internally by means of the mix blocks and
LFE controls provided on channels 3 and 4, channel 4 being the SMPTE/ITU and Realiser-default
subwoofer channel. This is an interesting opportunity to discover and compare how a real system
without redirection
would
sound
if
it had redirection, and the virtual redirection may well be preferred.
In these cases, because the relationship of the LFE level and the redirected bass level must be
preserved,
SW REL VOL
is not used for compensation. Instead, within the virtual subwoofer menu
at
MENU-SW
, the controls at
SW vSPKR SETUP1
are used as follows.
Set
LPF MIX
to
YES
. Set the
MIX BLOCK
coefficient for
SW
to
0.0
. Set the
MIX BLOCK
coefficients for all other active channels and
LFE GAIN
as shown in the following table.
LFE
GAIN
is in dB; the
MIX BLOCK
coefficients are gain factors,
1.0
representing no reduction and
0.3
representing -10 dB. As in the earlier tables, the
LFE GAIN
setting depends on both the
incoming LFE level (playback system) and the LFE level in the PRIR (measured system), so that the
sum of columns 3-5 is the d10 dB LFE gain. The
MIX BLOCK
coefficients depend only on
the LFE level in the PRIR (measured system) and are set so that if there is gain in the PRIR subwoofer
it is offset by reduction in the mix block.
Measured system
Playback system
LFE at Realiser input
PRIR SW
Realiser LFE GAIN
MIX BLOCK
LFE gain upstream
LFE gain + LF redirection in Realiser
0
0
+10
1.0
LFE gain downstream
LFE gain + LF redirection in Realiser
0
+10
0
0.3
LFE gain upstream
LFE gain upstream, LF redirection in Realiser
+10
0
0
1.0
LFE gain downstream
LFE gain upstream, LF redirection in Realiser
+10
+10
-10
0.3
[continued on next page]
