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PLM Series Operation Manual
current sensitivity/offset value, and using the rotary
encoder.
All input selection and sensitivity parameters may also
be adjusted from the DLC PLM Edition software.
9.12.3.2 IsoFloat
This option is selected by pressing soft button 4
(
IsoFloat
) from Menu
è
Input Cfg.
The PLM’s analog inputs utilize Dolby Laboratories’
IsoFloat patented transformerless electronic balancing
circuitry. This provides electrical isolation from an
analog source comparable to that achieved with
transformer-based designs. However, pin 1 of the
XLR input connector may be connected to ground
within the PLM if desired. This option is selected by
using the rotary encoder to toggle between
Floating
and
Grounded
. It may be necessary under some
circumstances to alter this setting to resolve ground
loop problems when using analog inputs. The IsoFloat
setting may also be adjusted from the DLC PLM
Edition software.
9.12.3.3 AEs/EbU input termination
This option is selected by pressing soft button 8 (
AEs
Term
) from Menu
g
Input Cfg.
Please see the warning regarding using AES/
EBU signals at section 6.2.1.
For fault-free operation when using AES/EBU digital
audio as an input source, inputs must be correctly
terminated with the characteristic impedance of 110
ohm. Whether a particular unit in an set of multiple
PLMs should have its AES/EBU input terminated will
be determined by the method used to distribute the
AES/EBU signals.
The rule is – if the PLM is at the end of a distribution
line, its setting should be
Terminated
. Otherwise, it
should be
Unterminated
. If an AES/EBU distribution
amplifier (DA) is being used to distribute the digital
audio signals, with one DA output per PLM, then all
terminations should be on. However, if the AES/EBU
link connectors are being used to “daisy-chain” the
PLM inputs together, then only the “last” PLM in the
chain should have its termination set on.
9 FRONT PANEL INTERFACE
Auto Select (default)
▸
Force Priority 1
▸
Force Priority 2
▸
Force Priority 3
▸
Force Priority 4
▸
Assignment of the inputs to the priority levels
A factory default setting assigns certain inputs to the
four priority levels automatically. These assignments
are:
Input Router 1:
Priority 1:
AES/EBU chapter1 (
AEs1
)
Priority 2:
Empty
Priority 3:
Empty
Priority 4:
Analog input 1 (
Analog 1
)
Input Router 2:
Priority 1:
AES/EBU chapter2 (
AEs2
)
Priority 2:
Empty
Priority 3:
Empty
Priority 4:
Analog input 2 (
Analog 2
)
These assignments may be changed by pressing
soft buttons 5 – 8 and using the rotary encoder to
scroll through alternative options. It is important
to appreciate that due to the signal type hierarchy
inherent in the input selection process, it is not
possible to select an analog source to a higher priority
than a digital source. For this reason, analog sources
are assigned to Priority 4 by the default setting. Note
that Dante inputs are not selectable from the front
panel of the PLM; their assignment must be made
from the DLC PLM Edition software.
Analog Input sensitivity and Digital Gain
Offset
The soft button adjacent to each of blocks 5 - 8 selects
either the input source (Line 2) or the input sensitivity/
digital gain offset (Line 3) for adjustment.
Line 3 of each block shows the currently set input
sensitivity (in the case of the analog inputs) or digital
gain offset (in the case of the digital inputs). The
maximum input level which can be accepted by the
analog input pre-amplifiers without clipping may be
set to 12 dBu or 26 dBu.
Digital gain offset may be applied to AES/EBU
digital input signals in 0.1 dB increments from -100
dB to +15 dB. This parameter may be adjusted by
pressing the associated soft button to highlight the
