DRP 393 MPEG-4 Receiver/Decoder
Rev. L
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Decoder audio
A 1 kHz test tone can be enabled for testing. The nominal level of the test tone is +6 dBm. The test tone is
available on all analogue outputs. The audio test output (6.3 mm phone jack) on the front side can be
connected on the four analogue outputs that are available. The level of the test output is -20 dBr relative to
the selected audio output.
DRP 393 has two audio decoders. Thus two audio streams (PIDs) can be decoded simultaneously. A dual
tone signal can be generated from both the decoded stereo signals via the function “Output 1 Dual Channel
Mode” that is then given out at the audio output 1. For this select “continuous” under Channel mode. The
“ZDF” particularly is transmitting an audio stream for blind people that is not sent continuously but only for
special broadcastings. This is indicated in a special identification signal (DC status). Select the mode
“EN301775 DC STATUS ONLY” for activation.
The amplification of all four audio outputs can be set separately. The setting range is -30 dB to +10 dB. 0 dB
corresponds to an audio output level of +6 dBm at a digital level control of -6 dBFS. Individual outputs can
be switched off with “MUTE”. The audio output signal at output 3 corresponds to the audio signal of output
1; accordingly the audio signal at output 4 is identical with the audio signal at output 2.
DRP 393 also has a digital SPDIF audio output. The audio signal of the audio decoder 1 is available at SPDIF
if selected. In the “BYPASS” mode the audio data stream is not decoded but directly routed to output. Thus
an AC3-encoded audio signal is available at the output and can be processed externally. In the “DECODED”
mode the audio stream is available as decoded signal. In the “DECODED AND DOWNMIX” mode a stereo
signal is generated from a multi-channel AC3 signal (e.g. Dolby 5.1).
For the analog stereo output there are two different types of stereo downmixes:
One type is a stereo-compatible “Dolby Surround Prologic” downmix, that is suitable for Dolby Surround Pro
Logic® decoding. This kind of downmix is also called Pro Logic or Left total/Right total (Lt/Rt).
The other type is a simple “Stereo” representation (called Left only/Right only, or Lo/Ro) suitable for
playback on a stereo hi-fi or on headphones. This signal can also be used to derive a mono signal.
