20
The
use
of
these
processors:
ISP-2022
and
ISP-1014
mandatory,
not
only
for
the
correct
functioning
of
the
acoustic
systems,
but
also
the
manipulation, substitution through other processors or active filters by the
user
will
change
these
parameters,
causing
an
immediate
void
on
the
guarantee granted by the manufacturer on these systems.
The main characteristics of the processors are the following:
6.1.- ISP-2022
This processor is only used when acquiring a DP-4 configuration.
Its
configuration
and
characteristics
turn
this
processor
into
a
vital
element in obtaining maximum performance of the sub bass enclosures of the
DP-4 system, that is, the SUB-218BS.
It comes installed and wired in a flight case, together with the Musicson
HE-1202 power amplifier.
Its main features are:
Two-way active filter with adjustable crossover frequency.
24 dB / Oct Linkwitz-Riley filters.
High pass and low pass filters for the sub bass way.
High pass filter for the mid-high way.
Variable gain for the low pass output
Adjustable delay between ways.
Phase inversion for the low pass.
All-pass or high-pass selector for the mid-high output.
Active power control circuitry preset by the manufacturer for the SUB-218BS.
- DESCRIPTION OF THE FUNCTIONS.
1. - LOW INVERSION: When this switch is on position “NO”, the mid-high
and low frequency filters are in phase.
At the “YES” position, these two outputs are in opposite phase (180º).
ATTENTION! The phase mentioned is referred to the electrical phase, NOT
the acoustical phase. It is possible that, in order to keep the (acoustic)
phase
of
the
sub
bass
way
output
in-phase,
the
electrical
phase
needs
to
be
inverted for some set-ups.
2. - LOW-HI FREQUENCY: This three-position selector allows selecting the
crossover frequency of both outputs, the values being 90, 120 or 200 Hz. The
switching affects simultaneously both ways.
For the DP-4 system the value to be selected is 90 Hz.
