The record output stereo audio is unprocessed. Composite video is not transcoded to
S-type video or vice-versa.
REMOTE INFRARED SENSOR JACK:
This miniature input jack, located on the rear
panel, accepts input from a remote infrared transmitter/sensor or remote key pad. It is
provided for custom installation applications. Consult your dealer or JBL for additional
application information.
ACCESSORY CONTROL OUTPUT:
This five-pin standard DIN jack located on the
right bottom corner of the SP MK II can provide trigger signals for an outboard control
box to turn on the system electronics, lower or raise a projection screen, dim or raise
room lighting, etc. Consult your dealer or JBL for additional application information.
DISPLAY CONTRAST CONTROL:
This manual rotary control is located on the under-
side of the left side of the front panel. The relative contrast of the liquid crystal display
can be changed with this control.
FINE TUNING YOUR AUDIO SYSTEM
The procedures outlined in the previous sections should allow proper performance of
the system. There are several things you can do to “tweak” the installation even further.
In many cases, the concepts contained in this section are not necessary to achieve
the kind of impact the SP MK II and a Home THX Audio System can provide. The fol-
lowing ideas and suggestions are for the most demanding installations, or when the
room itself presents a special challenge.
ACOUSTICAL PROBLEMS IN LISTENING ROOMS
The Home THX Audio System addresses many of the problems common to high quali-
ty reproduction of music or soundtracks in a home environment. For example, the dis-
persion pattern of the front LCR speakers minimizes the effects of floor and ceiling
reflections. Still, there are many variables which are beyond the control of a manufac-
turer. Room reflections create spurious false images and “comb filter” interference
effects which alter the tonality of the system while degrading the localization of specific
sounds. Larger rooms sustain echoes which degrade dialog intelligibility and detail. All
rooms have standing waves which emphasize certain frequencies at the expense of
others, based on the dimensions of the room.
Other concerns include environmental noise, which is often greater than people real-
ize. Although they might become accustomed to its presence and “tune it out,” it still
reduces the perceived low-level resolution of the system. In addition, the profound
bass capabilities of a Home THX Audio System can create distracting rattles which
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