PRESONUS ULT-series, Owner'S Manual

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3 Hookup
3.2 Onboard Performance Monitoring
ULT-series
Owner’s Manual
13
Natural. This changes the bass response of your ULT18 to
provide less low-end extension and more punch.
Polarity. The Polarity button reverses the polarity of the summed input
signal. The LED will illuminate to indicate that the polarity is reversed.
Power User Tip:
Reversing the polarity can improve the system’s response
when low-frequency waveforms from the subwoofer are reinforced or
cancelled by waveforms from another subwoofer or from the low-frequency
drivers of the full-range loudspeakers. This is a complex interaction
that also includes room acoustics, so setting is best done “by ear.”
Mono Switch. The Mono switch sums Inputs 1 and 2 and patches the
summed signal to Outputs 1 and 2. This feature is especially useful when
running stereo full-range systems with multiple mono subwoofers.
3.2 Onboard Performance Monitoring
Performance Monitoring. These three LEDs display the
performance status of the internal amplifier:
• Signal. Illuminates green when a signal is present at the input.
• Clip. Illuminates red when the input signal reaches 0 dBFS. At this level,
the signal will exhibit signs of clipping (distortion), and the analog-to-
digital (ADC) converter (and therefore the amp) will be clipping.
• Thermal. Illuminates red when the amplifier power supply or
output stages exceed thermal limits. The amplifier will mute until
the temperature drops below the thermal-limit threshold.
Power User Tip: Never run your input levels higher than the channel inputs can handle.
If you overdrive the A/D converters, it will cause digital
distortion (digital clipping), which sounds terrible.
3.3 Power
AC Line Connection. ULT-series loudspeakers have a universal power supply
that accepts AC power input between 100 and 250 VAC at 50/60 Hz. Each
loudspeaker is supplied with an IEC cord appropriate for the country of sale.
WARNING: Do not remove the center grounding prong or use a
ground-lift adapter, as this could result in electric shock.
Power Switch. This is the On/Off switch.
Power User Tip:
If connecting multiple loudspeakers to the same
electrical circuit, make sure that adequate line current is available.
Maximum current draw for each ULT-series loudspeaker is 5.45 Amps.
Natural Natural
0
Mono
100-230V~, 50-60 Hz, 150W
POWER
On/Off