Crown Audio IQ P.I.P.-DSP User Manual

Page 19

Page 19

IQ–P.I.P.–DSP Programmable Input Processor with DSP for IQ Systems

Reference Manual

filter is commonly used to feed the high
frequency portion of an audio signal to horns or
tweeters. It can be combined with a low-pass
crossover filter to create a band-pass crossover
filter for driving mid-range drivers.

Passband gain:

Fixed at unity.

Frequency:

Sets the –3 dB corner frequency of

the filter. The range is 20 Hz to 20 kHz.

Shape:

Sets the response shape of the filter.

Available response shapes are: 1st-order
Butterworth, 2nd-order Butterworth, 3rd-order
Butterworth, 4th-order Butterworth, 2nd-order
Bessel, 3rd-order Bessel, 4th-order Bessel and
4th-order Linkwitz-Riley.

Parametric Equalization Filter

Description: This filter boosts or cuts a relatively
narrow frequency band like a band-pass filter. It
is commonly used to correct specific anomalies
in the response of drivers.

Passband Gain:

Sets the amount of boost or cut

for the filter. The range is +12 dB to –24 dB.

Frequency:

Sets the center frequency of the

filter. The range is 20 Hz to 20 kHz.

Sets the width and slope of the filter. The

range is 0.1 to 30. The lower the Q, the wider the
filter and the better the transient response and
visa versa.

CAUTION: Avoid excessive Q’s.

Low-Pass Equalization Filter

Description: This filter combines the functions of
the parametric equalization filter to boost or cut
a relatively narrow frequency band with a low-
pass filter to roll of the frequencies above the
center frequency. It is commonly used to create
a B

(6th-order Butterworth) response in a vented

loudspeaker enclosure.

Note: The low and high-

pass equalization filters can be cascaded to
form unique inter-order crossover-type filters.

Frequency:

Sets the center frequency of the

filter. The range is 20 Hz to 20 kHz.

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.

CAUTION: Avoid excessive Q’s.

High-Pass Equalization Filter

Description: This filter combines the functions of
the parametric equalization filter to boost or cut
a relatively narrow frequency band with a high-
pass filter to roll of the frequencies below the
center frequency.

Note: The low and high-pass

equalization filters can be cascaded to form
unique inter-order crossover-type filters.

Frequency:

Sets the center frequency of the

filter. The range is 20 Hz to 20 kHz.

Sets the width, slope and gain of the filter. The

CAUTION: Avoid excessive Q’s.

Low-Pass Shelving Equalization Filter

Description: This filter boosts or cuts low
frequencies by the specified amount of gain.
Note: When used to cut rather than boost, the
filter acts like a high-pass 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.
Note: 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 common to
constant directivity 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.

Note: 1st, 2nd, 3rd and 4th-order responses result in 6,
12, 18 and 24 dB/octave roll-offs, respectively.

Note: The filters are not disabled by the ASA control.