Signal Delay; Peak Voltage Limiter; Average Power Limiter; Clip Eliminator - Crown IQ-PIP-USP2 Reference Manual

Q: Sets the width, slope and gain of
the filter. The range is 0.1 to 30. The
lower the Q, the wider the filter, the
lower the gain and the better the
transient response and visa versa.
Gain examples: A Q of 2 will result in
6 dB of gain at the center frequency
and a Q of 4 will result in 12 dB of
gain.
High-Pass Equalization Filter
Description: This filter combines the
functions of the parametric equal-
ization filter to boost or cut a rela-
tively narrow frequency band with a
high-pass filter to roll of the frequen-
cies below the center frequency.* It
is commonly used to create a B
6
(6th-order Butterworth) response in
a vented loudspeaker enclosure.
Frequency: Sets the center fre-
quency of the filter. The range is 20
Hz to 20 kHz.
Q: Sets the width, slope and gain of
the filter. The range is 0.1 to 30. The
lower the Q, the wider the filter, the
lower the gain and the better the
transient response and visa versa.
Gain examples: A Q of 2 will result in
6 dB of gain at the center frequency
and a Q of 4 will result in 12 dB of
gain.
Low-Pass Shelving Equalization
Filter
* The low and high-pass equalization fil-
ters can be cascaded to form unique
inter-order crossover-type filters.
Page 24
IQ-PIP-USP2
Description: This filter boosts or cuts
low frequencies by the specified
amount of gain. When used to cut
rather than boost, the filter acts like
a high-pass filter rather than a low-
pass filter. It has a fixed 1st -order
slope (6 dB/octave).
Passband Gain: Sets the amount of
boost or cut for the filter. The range
is +12 dB to –24 dB.
Frequency: Sets the –3 dB corner
frequency of the filter. The range is
20 Hz to 20 kHz.
High-Pass Shelving Equalization
Filter
Description: This filter boosts or cuts
high frequencies by the specified
amount of gain. When used to cut
rather than boost, the filter acts like
a low-pass rather than a high-pass
filter. It has a fixed 1st-order slope (6
dB/octave). It is commonly used to
compensate for the natural high-
frequency roll-off of constant direc-
tivity horns.
Passband Gain: Sets the amount of
boost or cut for the filter. The range
is +12 dB to –24 dB.
Frequency: Sets the +3 dB corner
frequency of the filter. The range is
20 Hz to 20 kHz.

4.4.6 Signal Delay

Signal delay can be set for each
channel. The delay for each channel
can be set using "Coarse" or "Fine"
adjustment controls:
"Coarse" Delay: Sets the amount of
signal delay. The range is 0 millisec-
IQ-PIP-USP2 Reference Manual
IQ-PIP-USP2
onds to 500 milliseconds in 1 milli-
second steps.
"Fine" Delay: Sets the amount of
signal delay. The range is 1.2916
milliseconds to 100 milliseconds in
20.83 millisecond steps. (The mini-
mum delay of 1.2916 milliseconds is
inherent in the DSP system design.)
The net delay through the IQ-PIP-
USP2 is the sum of the coarse and
fine delay settings. Use of both con-
trols provides a means for greater
delay control. For example, the
Coarse Delay control can be ad-
justed to provide cabinet-to-cabinet
alignment, while the Fine Delay con-
trol can provide alignment within a
cluster or cabinet.

4.4.7 Peak Voltage Limiter

This limits the peak voltage output of
the amplifier. There are four param-
eters which control this limiter.
On/Off: Turns the limiter on or off.
Attack: Attack time is adjustable
from 10 milliseconds to 100 millisec-
onds per 10 dB of overdrive.
Release: Release rate is adjustable
from 100 milliseconds to 10 sec-
onds per 10 dB or release.
Threshold: Absolute voltage thresh-
old is adjustable from 12 Vpk to 255
Vpk in 1 volt steps.

4.4.8 Average Power Limiter

Limits the long-term power output
from the amp. The actual output
limiter threshold is determined by
an absolute power threshold and
the nominal load impedance set-
ting. There are five parameters which
control this limiter.
On/Off: Turns the limiter on or off.
IQ-PIP-USP2 Reference Manual
Average Power Threshold: The
threshold is adjustable from 10 to
1000 watts.*
Nominal Load Impedance: The
nominal load impedance is settable
from 1 to 1000 ohms, and should be
set to correspond to the nominal
impedance rating of the load con-
nected to the respective channel.
Attack Time: Adjustable from 1 sec-
ond to 30 seconds in 1 second in-
crements.
Release Time: Adjustable from 1
second to 30 seconds in 1 second
increments.

4.4.9 Clip Eliminator

This limiter eliminates amplifier clip-
ping by monitoring IOC signals. The
only control for this limiter is On/Off.

4.4.10 Thermal Limiter

A thermal limiter is provided to limit
amplifier output as a function of avail-
able thermal headroom, allowing
smooth system level reduction while
preventing amplifier overload. There
are four parameters which control
this feature:
On/Off: Turns the thermal limiter on
or off.
Threshold: Sets the thermal level,
in percent, above which limiting will
begin. The range is from 1 to 100%.
Attenuation: Sets the amount, in
dB, that the input signal level will be
attenuated for each percentage
point that the thermal level exceeds
the trigger level. The range is ½ to 6
* The average power threshold should
be set per the loudspeaker's "long-
term" power rating (consult your
speaker documentation).
Page 25