3
7. LF Rolloff
For operation with a subwoofer, the LF Rolloff
switch shuts off the low frequency boost and
filters out signals below 100 Hz. It’s not necessary
to use this switch for speech applications
because the Mic input already has a high pass
filter. This switch only affects the signals to the
internal amplifier and does not affect signals
going out from the internal mixer, or to signals
passing through the Link connections.
8. Mixer On/Off
The Mixer On/Off switch turns the NX750P’s
internal mixer on the rear panel on and off.
The NX750P’s mixer should be used when a
microphone or CD player is directly connected
to one of the NX750Ps Line/CD or Mic inputs. It
should be switched off* if the NX750P’s Link Input
is connected to a separate mixer’s output.
*Note: the NX750P has been designed to
enable the user to interconnect multiple
NX750Ps (up to 12 or even more) via the Link
Inputs and Outputs. When linking NX750P's,
a maximum of 3 of the NX750P’s internal
mixers can be used (activated) allowing up
to 3 microphones and 3 line sources to be
mixed without an external mixer. This is useful
for smaller music engagements, meetings,
seminars, etc.
9. Mic Control
This control adjusts the volume level the Mic
input. The microphone signal output to other
cabinets through the link connections will be
affected as well.
10. Line/CD Control
This control adjusts the volume level of devices
plugged into the Line/CD input. The signal out
to other cabinets, from this device, through
the link connections will be affected as well.
A line-level signal and microphones can be
connected simulataneously.
11. Treble and Bass Controls
These controls affect the signals from devices
plugged into the Line/CD and Mic inputs. The
signal out, to other cabinets, through the Link
will also be affected. These controls do not
affect signals coming into the cabinet from
the Link connections.
12. Green PWR LED
Illumination indicates that AC power is on and
the fuse is functioning.
13. Yellow Limit LED
This indicates that the cabinet is operating
at full power and the limiter(s) are actively
reducing the signal level. It’s all right to
operate in limiting as long as the clip light is not
constantly on. The Limit light does not indicate
low frequency processing action. There are
separate limiters for the woofer and horn. This
LED will indicate operation of either limiter.
14. Red Clip LED
The illumination of this LED indicates that
the signal level is excessive and may cause
distortion. Reduce mixer levels or turn down the
Level control (on NX750P) to reduce clipping.
15. Power Switch
This turns the power On and Off to the
cabinet. Note; a cabinet that is turned off,
but is one of the cabinets in a chain might
cause hum (or buzz) in the other cabinets.
16. Fuse
The mains fuse should never blow even in
extreme operating conditions. A blown fuse will
generally mean that excessive mains voltage
has been applied or there’s a serious fault with
the unit. Self re-setting thermal switches are
built into the power transformer as well as on
the internal heat sink. These will not trip even
under the most extreme operating conditions
and are provided only for safety reasons.
Thermal margins may be compromised when
operating facing straight up, straight down or
while operating in direct sunlight!
A note about unbalanced operation: When connecting an unbalanced source (such as a mixer with RCA
outputs) to balanced inputs such as an NX750P, the best hum rejection can be achieved by running a
balanced connection right to the unbalanced plug. The return connection should be connected to ground
at the unbalanced plug. The NX750P does not connect the AC power ground directly to the input signal
ground. This will eliminate most ground problems.
