Sound Devices PIX 220i - Manual (Page 33)

Power Loss During Recording
In the event that power is lost during recording (External and attached L-Mount batteries), the PIX
recorder will attempt to recover the file when next powered on. The recovery process uses an auto-
save feature during recording that operates on a 30 second interval.
Alignment of Audio and Video
An advantage to recording audio on the PIX recorders along with the video is the elimination of
audio/video sync problems in post. The PIX recorders have many options regarding audio sources
along with the two options for video inputs, HDMI and SDI. Given this flexibility, care still must be
taken to ensure good audio/video sync.
If recording camera audio embedded on HDMI or SDI, then the audio/video alignment will be excel-
lent provided the alignment is proper on the camera.
Most cameras have a delay of one or more frames from camera sensor to SDI/HDMI output. By
default, audio signal sent into the PIX recorder on AES or analog audio inputs is not delayed. This
results in an offset between the audio and video that must be corrected. The Setup Menu options
Audio  Input 1-4 Delay allow a delay of up to 500 milliseconds to be applied to each audio input
independently. The amount of delay required to synchronize audio and video will depend on the
specific camera model and settings. Record a test file with sticks or a clap and measure the offset to
determine what delay to use. ( See “Input Delay”, page 22 )
When input audio is delayed, it is delayed to the recorded video file and to the audio outputs as
well. This behavior can be modified such that the audio to PIX recorder’s line outputs is not delayed.
This is particularly useful if feeding the line output audio back to the camera as a guide audio track.
Change the Setup Menu option Audio Input Delays to Output to Off to disable the audio delay to the
line outputs.
Recor
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PIX 220i and PIX 240i Video Recorder User Guide
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