Specifications

2 The Multisonic Imager
6
Each side-channel output has a portion of the
opposite channel subtracted, with the exact
proportion and level for the side channels precisely
maintained, according to the C/S Image Balance
control position.
The center channel is created by summing the
processed left and right output signals. This signal
will always be 6 dB higher (louder) with any
center-panned signal information, compared to
side-panned signal information. The exact level of
the center channel is precisely maintained for
correct operation. Once the system is set up, there
is no need for concern about the center channel
loudspeaker level. It is always exactly correct.
This concept, combined with vector-sum acoustic
imaging—the process which creates a phantom
image between or beyond two or more
loudspeakers—results in any two loudspeakers
effectively reinforcing the imaging location of the
third loudspeaker. This increases the perceived
separation between any two of the three channels
beyond that provided by the electrical separation.
The Multisonic Imager creates the theoretical
maximum of 6 dB of electrical separation between
any two of the three channels. This in itself is
enough to effectively localize a sound source, but
the separation is further increased subjectively with
the use of quality loudspeakers and a good acoustic
environment. The acoustic interaction of the three
loudspeakers causes a focusing effect which can
eliminate the perception of any electrical crosstalk.
When a signal is panned to a particular
loudspeakerlocation, the other two loudspeakers
will effectively reinforce that loudspeaker
∗
s imaging
location. If a signal is panned to a location between
the loudspeakers, all three loudspeakers together
point to that specific sound-source location.
At the midpoint between left and center and
between right and center, the opposite loudspeaker
is canceled completely, leaving the two
loudspeakers to create a phantom image midway
between them. This is essentially the same principle
that creates the phantom-center image in
conventional left-right systems. But in this case the
phantom locations at left-center and right-center will
be more clearly defined because of the closer
spacing (one-half the distance) between the
adjacent loudspeakers in comparison to a
two-channel system.
The C/S Image Balance control is integral to the
Multisonic circuit. It allows adjustment of the matrix
parameters which control the relative levels and
effective width of the stereo sound stage. This
allows compensation for any variation in the stereo
width of the mix. Differences in image width or
perspective can be caused by the use of different
microphone configurations for the recording, as well
as different playback loudspeaker configurations.
The C/S Image Balance control can compensate for
these factors so that optimum imaging can be
achieved.
Alternatively, this control can be simply left in the
center or in a preferred position. The system will
then reveal what was recorded in the program
material without the need for any user intervention.
2
The Multisonic
®
Imager
Stereo Inputs
The primary function of the M44 and M86 is to
convert a standard stereo input signal, with left and
right input connections, to a Multisonic output signal
with left, center, and right outputs. In addition, a
subwoofer output and two surround outputs are
provided for a complete multichannel listening
experience with any left-right stereo signal source.
Up to four stereo input pairs can be simultaneously
connected to the M44 or M86. A pair of balanced
XLR input connections are provided, as well as
three pairs of RCA unbalanced inputs. These four
pairs are mixed together to form the left and right
stereo source. The RCA inputs have 7 dB additional
gain compared to the XLR inputs. The input sources
for left and right are separately mixed together at an
equal ratio. The M86 can handle a fifth stereo input
as part of the 5.1 connection (see below).
The Input Gain control allows adjustment of the
level of the stereo input mix. The C/S Image
Balance and Derived Surround level controls allow
convenient adjustment for perfectly balanced sound
staging of the stereo sources.
LED indicators show the output levels, which are
adjustable using the Subwoofer, Center, Left/Right,
and Surround output controls.
5.1 Inputs (M86 only)
A set of 5.1 input connections allows seamless
integration of any discrete 5.1 source in the sound
system. These inputs normally route to the
corresponding outputs on the M86. A separate gain
control is provided to adjust the level of the 5.1
source. This can be used with any DVD player that
has 5.1 analog outputs (that is, it has built-in digital
decoding).
A switch is provided to route the left and right inputs
of the 5.1 source through the Multisonic process.
This can be used for 5.1 sources which lack a
center signal; the result will be much more effective