Crown VFX2 Instruction Manual page 14

2.4.3 Output Connections
Six outputs (high pass, low pass and bandpass —
both balanced and unbalanced) are available from
the VFX2. Details are described below.
a. Unbalanced High Pass Output
To pick up an unbalanced high pass output from
the VFX2, insert a 2-conductor, 4%" phone plug wired
as shown in Figure 2-4, into the HIGH PASS NORMAL
output jack on the rear panel of the VFX2.
b. Balanced High Pass Output
To pick up a balanced high pass output from the
VFX2, insert a 2-conductor, 4" phone plug wired as
shown in Figure 2-4, into both the HIGH PASS
NORMAL and the HIGH PASS INVERTED phone
jacks. Thetips of the two 4" phone plugs become the
two sides of the balanced line. The barrels become
the ground or center tap.
c. Unbalanced Low Pass Output
To pick up an unbalanced low pass output from
the VFX2, insert a 2-conductor, 4" phone piug wired
as shown in Figure 2-4, into the LOW PASS NORMAL
output jack on the rear panel of the VFX2 and set the
MODE switch to CROSSOVER (LOW PASS).
d. Balanced Low Pass Output
To pick up a balanced low pass output from the
VFX2, insert a 2-conductor, 4" phone plug wired as
shown in Figure 2-4, into both the LOW PASS
NORMAL and the LOW PASS INVERTED phone jacks
on the rear panel of the VFX2. The tips of the two 4%"
phone plugs become the two sides of the balanced
line. The barrels become the ground or center tap.
Set the MODE switch to CROSSOVER (LOW PASS).
e. Unbalanced Bandpass Output
To pick up an unbalanced bandpass output from
the VFX2, insert a 2-conductor, 4" phone plug wired
as shown in Figure 2-4, into the LOW PASS NORMAL
phone jack on the rear panel of the VFX2. Set the
MODE switch to FILTER (BANDPASS).
f. Balanced Bandpass Output
To pick up a balanced bandpass output from the
VFX2, insert a 2-conductor, 4" phone plug wired as
shown in Figure 2-4, into both the LOW PASS
NORMAL and the LOW PASS INVERTED phone jacks
on the rear panel of the VFX2. The tips of the two 4"
phone plugs become the two sides of the balanced
line. The barrels become the ground or center tap.
Set the MODE switch to FILTER (BANDPASS).
13
2.4.4 Glossary of Filter Terms
a. Crossover Network
A selective network used to divide the audio
frequency output of an amplifier into two or more
bands of frequencies. The band below the crossover
frequency is fed to the woofer loudspeaker, while the
high-frequency band is fed to the tweeter. Also called
dividing network and loudspeaker dividing network.
b. Crossover Frequency
The frequency at which a dividing network
delivers equal power to the upper and lower
frequency channels when both are terminated in
specified loads.
c. Bandpass Filter
A filter that transmits alternating signals whose
frequencies are between given upper and lower
cutoff values, while substantially attenuating all
frequencies outside this band.
d. Corner Frequency
A frequency at which the filter goes from a
condition of passing the signal unattenuated to
"rolling off" or attenuating the signal according to its
frequency. It is also sometimes referred to as the
"cutoff" frequency or the "break" frequency. It is also
defined as 3dB below the maximum output.
2.5 OPERATION
Most modes of operation depend upon the selection
of various input and output combinations which are
required by a specific system configuration. The
following notes apply to input selection.
a) A balanced input must be inserted into the
(BALANCED) INPUTS on the VFX2 rear panel. See
paragraph 2.4.2 a for wiring a balanced input phone
plug. A balanced line input has an adjustable
attenuation (LEVEL) potentiometer adjacent to the
input jack.
b) An unbalanced input may be inserted into the
(BALANCED) INPUTS or theUNITY GAIN INPUTS on
the VFX2 rear panel. See paragraph 2.4.2 b for wiring
an unbalanced input phone plug. An unbalanced
input, connected to the (BALANCED) INPUT jacks,
has a variable attenuation (LEVEL) potentiometer.
When the unbalanced input is connected to the
UNITY GAIN INPUT jacks, the variable attenuator
(LEVEL) adjustment is removed from the circuit and
the line has a fixed unity gain.