Cobalt Networks 9323 owner manual AES Audio Input Advanced Features

Embedded Audio

The 9323 supports all four groups (16 channels) of embedded audio at full 24 bit resolution in both SD (with extended data packets) and HD.

Analog Audio

The 9323 supports 8 channels differential analog audio. The analog audio is encoded in such a way as to make +24 dBu (analog) equivalent to 0 dBFS (digital). Analog audio conversion can be disabled to reduce power consumption.

Discrete AES Audio Input

The 9323 can accept 16 channels (8 pairs) of discrete AES audio on 75 ohm BNC connections. The AES must have a nominal rate of approximately 48 kHz. Sample rate conversion is employed to account for minor clock rate differences in the AES stream and the input video stream. However, the card does not support AES input at 32 kHz, 44.1 kHz, 96 kHz or 192 kHz rates.

Discrete AES Audio Output

The 9323 can emit 16 channels (8 pairs) of discrete AES audio on 75 ohm BNC connections. The AES clock rate will be precisely locked to the output video rate.

Dolby E Decoding

Dolby E decoding is available as an optional feature. It allows decoding from a discrete AES source, or an embedded audio pair. The decoder will return up to 8 decoded channels (according to the Dolby E sub-format) plus a 2 channel down mix for monitoring. All 10 of these channels are available as inputs to the audio router.

AES Audio Input Advanced Features

AES Sample Rate Converter Bypass

The card’s AES inputs have built in sample rate converters that are enabled by default. This allows the card to interface with asynchronous AES sources (sources who’s AES timing does not match the video reference timing.). They can be bypassed with a control in Dashboard or the front panel. This is a necessity when trying to embed non-PCM AES audio such a Dolby E or Dolby Digital audio streams. This control is off by default.

Zero-Delay Audio Embedding

Sometimes it is desirable to embed AES with minimum latency. For example, if you want to embed Dolby E audio into video with no latency, and delay the video by one frame to account for Dolby E encoding delay. By turning this control on for a given AES pair, the pair will be directly embedded into it’s corresponding group, bypassing the normal frame sync audio delay. (AES Pair 1 into Embedded Group 1, ch1 & ch2, AES pair 2 into Embedded Group 2, ch3 & ch4). This control overrides the standard audio routing system: if AES Pair 1 is selected, then the controls to route into Embedded group 1, ch1 & ch2 don’t apply. There is no gain or polarity control available when this option is selected. This control is off by default

9323 Owner’s Manual • (V 2.1) Page 9 of 28