Operation Manual
5. Operation and performance
C SERIES Operation Manual rev 2.0.0
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Most power amplier designs, when bridged, automatically introduce a +6 dB input gain boost which can lead the
user to conclude that said amplier delivers “more than double the power” when in bridge mode. This is clearly not
the case, as the gain boost articially enhances perceived power at the cost of headroom. The C Series ampliers
work on globally set constant gain, and automatically compensate the input gain by -6 dB. For example, if the
amplier is congured in a three channel mode, then the selected gain is maintained from input to output on all
channels, discrete or bridged.
5.4.4. Amplifier Input Gain
All C Series ampliers feature adjustable input gain. This versatility enables the amplier to accommodate a
multitude of system congurations with various input sources and speaker layouts.
Amplier gain is set globally for all channels on four-channel models, and in four-channel groups (A-D and E-H)
on eight-channel models. The range is 29-38 dB in 3 dB increments. Individual channel ne level adjustment is
available using the potentiometers on the front panel.
The unique adjustable input gain feature of the C Series makes it easier to attain the optimum balance between
headroom and signal-to-noise ratio in the signal path. A weak signal at the input might require the gain to be raised
in order to achieve maximum output power with the lowest signal-to-noise ratio. A “hot” input signal, however,
would require a lowering of the gain to avoid sending the amplier into Voltage or Current clipping.
See Appendix for a table containing Gain versus VPL setting implications for input sensitivity and output power.
Connect the positive (+) loudspeaker cable to the positive (+) red terminals. Connect the negative (-) loudspeaker
cable to the negative (-) black terminals. For bridge mode, connect the positive (+) terminal on Channel A to the
positive (+) loudspeaker cable and the negative (-) terminal on Channel B to the negative (-) loudspeaker cable.
5.4.4.1. Channel gain/level (front-panel pots)
Individual channel gain (level) may be adjusted using the potentiometers located on the front-panel behind the dust
lter cover. Range is from 0 dB to -innity in 21 steps. The attenuation is logarithmic, with the 12 o’clock position
indicating -10 dB.
Use your ngers or a screwdriver to adjust the potentiometers.
NOTE: If the level control is used to attenuate to a lower level than the headroom relative to input
sensitivity AND the amplier input is driven into clip, there is a danger of clipping the input stage before
the current or voltage peak limiters are activated.