CX261 Installation and User Guide v1.5
14
SETTING UP & OPERATION
Music Inputs
Gain & level
To avoid dramatic changes in volume when switching between
sources, the CX261’s music inputs are provided with preset
gain trim controls ([2] on “Description of rear panel” on
page 9
). These vary the input sensitivity from -12 dBu to
+12 dBu (approx. 200 mV to 3.1 V). When setting the system
up, play audio from all the sources in use and listen to them
one at a time at a reasonable volume. Taking a source of
“average” volume as the reference, the gain controls of the
others should be adjusted so that there is no appreciable
difference in volume between any of the sources. (With
a typical music source, setting the gain on its channel to
mid-way is a good starting point.) Note that consideration
may need to be given to the type of programme in use,
particularly if one or more sources are TV sound.
In normal operation, the music level is set with the
MUSIC
LEVEL
control on the front panel ([2] on “Description of
front panel” on page 8
). This control will not be operative
if the rear panel
LOC/REM
push-button is set to REM. When
setting the audio system up, set the gain controls (if any) on
the power amplifier(s) to minimum, then turn the
MUSIC
LEVEL
control on the mixer to maximum. Then increase the
zone volume by turning up the power amplifier gain until it is
as loud as will be required in normal use. This method ensures
that excessive volumes will not be possible with the mixer’s
operational controls.
Note that the setting of the
MUSIC LEVEL
control has no
effect on microphone or paging volume.
Front panel MP3 input
The MP3 input is enabled by setting the rear
panel
LINE 1/MP3
switch to MP3, and then selecting
LINE 1/MP3
on the front panel
MUSIC SOURCE
selector
switch. To allow for the wide range of signal levels which may
be encountered from portable audio devices, the MP3 input is
provided with its own level control and signal level LEDs ([5]
and [7] respectively at page 8
). The range of sensitivity
adjustment is from -20 dBu (with the control fully clockwise,
at “20”) to +4 dBu (with the control fully anticlockwise at
“-4”).
Three LEDs are fitted to the front panel to aid level adjustment.
The LEDs illuminate at the levels shown in the table:
LED
LEVEL
Green
-21 dBu
Yellow
-6 dBu
Red
+1 dBu
With an MP3 player (or other source) connected to the MP3
input and playing, and the MP3 input selected, the level control
should be adjusted so that the green and yellow LEDs are on
more or less continuously and the red LED only on during the
louder passages.
Local/remote control
If an RL-1 or RSL-6 Series remote control plate is in use,
the rear panel
LOC/REM
push-button must be set to REM
(button in) for the remote control to be operative and for the
corresponding front panel controls to be disabled. If remote
control is not required, the switch should be left at LOC
(button out).
The setting of the internal PCB jumper J14 is also relevant.
The default setting for this jumper is SW. This means that
music source selection for the zone will be determined by
the zone’s rear panel
LOC/REM
switch position: it will be via
the front panel
MUSIC SOURCE
control when it is set to
LOC and via a remote plate or other external control when
it is set to REM. If J14 is moved to its alternative setting of FR,
the source selection will always be made with the front panel
control whatever is connected at the rear panel or the setting
of the
LOC/REM
switch. If external control of music level
only (i.e., not source selection) is required, the jumper should
be set to FR and the
LOC/REM
switch to REM.
The diagrams below summarise the options:
SWITCH = LOC/REM (OUT)
J14 = SW
SWITCH = LOC/REM (OUT)
J14 = SW
SWITCH = LOC/REM (IN)
J14 = FR
SWITCH = LOC/REM (IN)
J14 = SW
