Installation
Folded Optics
Audio/Video
Synchronization Issues
➤
In rear screen applications where space behind the projector is limited, a mirror may be
used to fold the optical path, as shown in Figure 3-5. The position of the projector and
mirror must be accurately set. If you are considering this type of installation, contact your
dealer for assistance.
Screen
Figure 3-5. Folded Optics
➤
Due to its extraordinarily high level of video processing performance, the DHD Controller
may distribute video signals with a perceptible level of audio latency. In order to easily
solve this issue, Runco recommends using the DHD Controller with a high-quality audio
receiver that has the ability to effectively synchronize audio and video signals.
Most mainstream audio receiver/switchers have the ability to synchronize the audio and
video to the Advanced Television Systems Committee (ATSC) prescribed tolerances.
According to the ATSC, the sound program should never lead the video program by more
than 15 milliseconds, and should never lag behind the video program by more than 45
milliseconds.
In addition, many video displays and A/V receivers introduce additional latency that needs
to be compensated for during the installation. Table 3-4 shows the amount of possible
audio latency given different signal input timings.
Table 3-4. Possible Audio Latency for Various Input Timings
Input Timing
480i
480p
576i
576p
720p/50
720p/60
1080i/25
1080i/30
1080p/24
1080p/50
1080p/60
Mirror
Possible Audio Latency (milliseconds)
20
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80
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