Tieline Bridge-IT, Руководство пользователя

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© Tieline Research Pty. Ltd. 2019
Bridge-IT Manual v4.0
8 Adjusting Input/Meter Levels
By default, the PPM METERS on the front of the codec, or in the HTML5 Toolbox Web-GUI, use
dBFS to express nominal operating, headroom and noise floor levels. The PPM meters display
input audio by default when the codec is not connected and then switch to monitor decoded return
program audio after making a connection.
Mono and Stereo Audio Capabilities
The codec routes input 1 directly to the left output and input 2 directly to the right output when it is
not connected.
To connect in stereo select a stereo algorithm in the IP Setup menu via Connect > IP > Tieline >
Setup . To connect in mono select a mono algorithm in the IP Setup menu. In mono the codec
mixes both inputs 1 and 2 together.
When a Bridge-IT codec answers a mono incoming call it feeds mono audio to both the left and
right analog XLR outputs, as well as the left and right AES3 outputs. Note: It is not possible to mix
channels 1 and 2 into dual mono outputs.
The codec feeds both analog and digital AES audio out at all times, whether the audio source is
analog or digital.
Adjusting Audio Meter Reference Scale Settings
The codec can also automatically adapt to different Tieline reference scales. A Tieline codec with
proprietary Tieline session data enabled will automatically adjust the reference level to suit G5 and
G3 codecs, or Report-IT, using the default
Auto reference level setting. When connecting to a
non-Tieline codec, or a Tieline codec without session data enabled, the codec will use the Tieline
G5 reference scale setting.
The default Tieline G5 audio reference scale displayed on the PPMs when you connect to a
Tieline G5 codec is -38dBFS to 0dBFS (e.g. Merlin, Genie, Bridge-IT and ViA codec families).
Using this reference scale audio peaks can safely reach 0dBFS without clipping, providing 18dB of
headroom from the nominal 0vu point.
Features Description
1
-38dBFS PPM meter low point
2
-18dBFS Nominal 0vu reference level at -18dBFS (+4dBu)
3
0 dBFS Peaks should not exceed 0dBFS when using analog audio to
prevent clipping (Note: it is impossible to exceed 0dBFS when
using digital audio)
4
PPM meter in clip PPM indication displays a solid section at the right-hand end
when audio is in danger of clipping
Bridge-IT, Genie, Merlin and ViA codecs have more audio headroom than Tieline G3 audio
codecs (Commander and i-Mix G3) and Tieline's Report-IT app, therefore the audio metering
reference scale needs to be adjusted when connecting to one of these products. The comparison