TC Electronic DB6, Руководство пользователя

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DB6: An introduction
DB6 English Manual (2014-10-07) 19
Thank you for choosing DB6 – the next step
in professional loudness control.
We want
to thank you for choosing this product, and we
hope it will serve you as a reliable, flexible loud-
ness processor for many years to come.
Consistency in loudness is the single most
important audio issue to get right in broad-
cast today.
DB6 employs cutting-edge tech-
nology allowing stations to avoid listener com-
plaints about jumping levels, while transmitting
both analog and digital signals with optimum
processing.
Keeping audio transparent
One of the finest things about new international
loudness standards is that a transparent signal
path is defined all the way from production to the
consumer. We therefore encourage you to take
advantage of DB6’s multiple ways of turning off
loudness processing for content that is already
normalized and suitable for a given platform.
Partial or full disabling of loudness processing
can be automatic or based on external signal-
ing. TC has taken initiatives to make such exter-
nal signaling part of open broadcast standards
– so expect new developments in this field. For
unknown content, rather than using DB6 to in-
flict “sausage processing”, use its built-in radar
meters to pull in loudness just enough. The goal
should not be to have all programs sit constantly
at Target level, but rather to have DB6 intervene
as a “safety belt” when something has gone
wrong upstream.
Production measurements such as Program
Loudness and Loudness Range will gradu-
ally make audio mixing more precise and down-
stream processing less needed. Therefore, re-
view your processing settings at regular inter-
vals, and be prepared to back them off as pro-
duction catches up.
DB6 and AC3 transmission
DB6 includes numerous functions to optimize
sound and logging when delivering to platforms
using the AC3 codec. While fixed AC3 metadata
recommendations in new ATSC and EBU guide-
lines means that there are fewer things that can
go wrong, the dynamics processor built into the
AC3 decoder (known as “DRC”) is still one of
the places where audio transparency tends to
get lost.
To prevent DRC from becoming the “sausage
processing” component of the signal path, we
recommended turning it off. DRC also isn’t
BS.1770 compliant, and the limited 20 dB head-
room in the “RF” path of AC3 can be dealt with
in better ways that are available in DB6.