TC Electronic DB4 MKII - Manual (Page 75)

ATX / DX
English Manual 71
ATX / DX
The inputs and outputs of this algorithm are dis-
tributed as follows:
Input Output
L
E1
E2
E3
E4
L
R R
Introduction
ATX and DTX algorithms combine BS.1770
based loudness correction, 5-band processing,
width control and true-peak limiting into compre-
hensive, low latency processors for stereo use.
Should AV sync be needed, these algorithms
also include 24 bit delay capable of being adjust-
ed without noise being generated, while audio
is passed. The DTX algorithm is ideal for digital
stereo transmission, and for trickle-down pro-
cessing to low loudness range platforms such as
“pod” and mobile. Note: Presets from TC’s DB2
processor are based on the DTX algorithm and
may also be directly transferred to DB4 or DB8.
The ATX/DTX algorithms can be operated in
three distinctively different modes:
– Stereo. In this mode, the Loudness, EQ and
Multiband sections operate in tandem: What-
ever gain change is applied to one channel, is
applied to the other. Also, many parameters
have mutual left and right controls.
– Dual Mono. In this mode the Loudness, EQ
and Multiband sections treat the two Input
signals completely independently.
– Stereo Wide. In this mode the apparent width
and image of stereo signal can be altered si-
multaneously with controlling loudness and
peak level. The left and right signal is internally
de-composed into an M (Mono) and S (Stereo)
component, and reverted to left and right sig-
nals before peak limiting on the Output.
ATX vs. DTX
Two different loudness control algorithms for
stereo signals are available:
– DTX, which is targeted to digital broadcast
and distribution, and
– ATX for analog broadcast or distribution.
The ATX is high res, low latency loudness con-
trol algorithm with adaptive emphasis limiting
for feeding analog transmission.
Variations between ATX and DTX are only ex-
posed on the Limiter page of the algorithm.
Therefore, all other pages are described as the
same in the manual section.
Reference Level
Reference Level defines the standard operating
level, and scales the Threshold and Target Level
parameters of the Loudness control and Multi-
band section. The Threshold of the Limiter is not
influenced by this setting, but is always relative
to 0 dBFS.
Typical Reference Level settings would be
-20 dBFS in USA and some parts of Asia, and
-18 dBFS in Europe, Japan and some parts of
Asia. With new loudness-based standards be-
ing adopted worldwide, Reference Level should
be set to the Target Level of a given station, or
1 dB higher. This would typically be in the -24 to
-21 dBFS range.
If you wish to relate all levels to 0 dBFS, leave the
Reference Level setting at 0 dBFS.
ATX / DX algorithm – main page
ATX / DTX algorithm main page
In Gain
Range: 0 dB to Off
Separate level controls for Left and Right Input
(A and B).