Technical Specification
Page B-6 Reference Guide: TT128x High Definition Professional Receiver/Decoder
ST.RE.E10141.5
Table B.3: Analogue Audio Performance Specifications
Parameter Conditions Limit
Gain 0 dBm input level ±1 dB
Frequency response 100 Hz - 15 kHz, 0 dBm input level ±0.2 dB
20 Hz - 20 kHz, 0 dBm input level +0.5 dB, -1 dB
Cross talk 0 dB input level, 100 Hz -80 dB
0 dB input level, 1 kHz -70 dB
0 dB input level, 10 kHz -60 dB
Distortion +8 dBm input level, 100 Hz -70 dB
+8 dBm input level, 6.3 kHz -70 dB
Noise RMS -65 dB
Phase 40 Hz to 15 kHz ±2°
Lip sync delay Depends on synchroniser configuration ±5 ms
B.3.3 Audio Routing
The IRD supports the following routing of audio signal:
• STEREO (Channel 1 left, Channel 2 right)
• MIXED TO BOTH (Channel 1 and 2 on left and right)
• LEFT TO BOTH (Channel 1 on left and right)
• RIGHT TO BOTH (Channel 2 on left and right)
When the input signal is STEREO, the Audio digital output format will
always be STEREO.
Where a dual mono service is available, it is possible to configure the
output as MIXED TO BOTH, LEFT TO BOTH and RIGHT TO BOTH.
B.3.4 Lip Sync
The audio at the output remains synchronous to the decoded video by
default (i.e. where both video and audio streams are available from the
same service). In such circumstances the video and audio streams share
the same PCR.
The lip sync error (delay from presentation of video until presentation of
audio) introduced by the Receiver is in the range of ±5 ms.
The lip sync delay between stereo pair 1 and 2 is ±2 ms because the PTS
will be presented independently for each pair.
When using frame sync the lip sync error is up to 40 ms due to audio
frame skip and repeats.
B.3.5 Supported Audio Specifications
Table B.4: Supported Audio Specifications
Specification Description
ISO/IEC 13818-3 Generic Coding of Moving Pictures and Associated Information: (MPEG-2) Audio.
ATSC A-52 Digital Audio Compression Standard (Dolby Digital).
SMPTE 302M Linear Audio (TANDBERG Television’s interpretation of the specification).