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Operating Manual - nX, nXe, and nXp Power Amplifiers
9.4a (continued) Software Control Surface - Channel
Stereo/Bridged Status
- This shows if a channel pair is in stereo or bridge mode
as set by back panel switch. In bridge mode, input signal is automatically taken from the
odd channel input and inverted, then sent to the even channel. The even channel controls
become disabled. Note that in bridge mode, the even channel software attenuators will still
reflect the physical position of the amplifier's front panel attenuators, even though they are
removed from control of bridged signal.
Channel Name
- This user defined text box names the amplifier output channel. Up
to 20 characters can be used.
Clip/Mute LED
- This LED shows when the amplifier output is either muted or
clipping. Clipping is indicated when the output level is 1dB below the output power supply
rails, and accurately tracks AC line voltage sags. This LED shows the same status as the
front panel clip/mute LED.
Mute Button
- This button mutes the output channel. Output mute can also be con-
trolled by the event scheduler, WR-5, or neWR-5 remotes.
Polarity Button (Pol)
- This button inverts the polarity of the output channel signal.
Input Meter
- This meter indicates the pre-fader amplifier input level in dBu.
Main Output Channel Fader
- This controls the output attenuation. Output attenu-
ation below -40dB mutes the output.
Output Meter
- This indicates the amplifier output level in dB below full rated output.
Protect Indicator (Prot)
- These indicate an overtemperature, overpower, or overvoltage fault on individual channels.
Current Meter (Cur)
- The Current LED shows that the amplifier is delivering current to a load, and is useful to de-
termine if a speaker load is open or shorted.
Temperature Meter (Temp)
- The temperature meter and text box shows the current operating temperature of the
output devices for each channel. Excess of 100°C will trigger overtemperature protection.
Offset Link Group and Offset Faders
- A group of output channels can be linked together to attenuate the group
as a whole without changing the relative levels of each channel. If a channel is assigned to one of the 16 offset link groups, a
colored triangle marker appears on the left side of the main fader graticule for secondary level control of all channels in that
group. Left click and drag this marker up or down to adjust the link group level. The actual main output channel faders can not
be linked to a group. Note that more than 40dB of cumulative channel attenuation causes the channel to mute.
In addition to the control surface offset link group attenuator control (not the main fader), most DSP functions have a link
group check box in their work window to assign a specific DSP parameter to one of 16 link groups if desired. Link groups can
be renamed by clicking on any group name and entering the new name.
Attenuators
- These two dials indicate the physical position of hardware level controls on either the amp front panel or
the remote DC level control. Note that these will display the position of attenuators even when they are disabled.
Total Attenuation
- This indicates the total amount of attenuation being applied to the channel. It is the sum of the fol-
lowing attenuation points: control surface fader, offset link group attenuation, front panel level control, and remote attenuator.
Note: The maximum dynamic range of the amplifier is achieved when the amplifier’s attenuation is set to the optimal
value. The amplifier’s front panel attenuators follow the DSP section but precede the power amplifier section (see
block dia-
gram
). Thus, the optimal setting for maximum dynamic range is determined by subtracting the amplifier's input sensitivity from
the maximum input signal of +20dBu. For example, when the back panel Gain DIP Switch is set for gain of 1.4V, the input
sensitivity is +5.1dBu (1.4Vrms = +5.1dBu). Su5.1dBu from +20dBu, and that results in 14.9dB attenuation required
for optimal dynamic range. For other input sensitivity values, see the
specifications
section.
9.4a - Control Surface
Channel Functions
