INSTALLATION
MOUNTING
The front panel is designed to fit a standard 19” rack at 3- l/
2” intervals or alternatively the unit may be stacked. NOTE:
When rack mounting the PRO5000, the rear of the amplifier
must be fastened to the rack via the rear mounting holes to
eliminate large torque forces on the faceplate. The feet may
be removed if desired when rack mounting.
VENTILATION
Do not block the air flow into or out of the amplifier. Air is
drawn in through the vents in the front panel, and is
exhausted out the side vents. Therefore, when rack mounting
in a cabinet, allow sufficient space between the inside walls
of the rack and the amplifier chassis, (at least 2 inches). If
the cabinet has
a
front door, the door must have large enough
vents to allow enough volume air flow for each amplifier in
the rack, (80 CFM per PRO5000 should be adequate). A
good alternative is to augment the air flow with a rack
mounted fan that pressurizes the space in front of the
amplifiers and/or evacuates the air space in the rear of the
cabinet.
The PRO5000 includes a removable dust filter assembly
attached to the outside of the front intake vents. This filter
should be removed occasionally and cleaned. To remove,
gently squeeze the ends inward and pull the filter frame
straight out from the front panel. The foam filter element
may then be removed from the frame and shaken or blown
out with compressed air. If the foam is particularly dirty, it
may be washed with mild soap and warm water. Replace-
ment foam elements are available from the factory, part
number
HWH-392
.
CONNECTIONS
AC LINE CORD:
High power output puts heavy demands on the AC supply
to the amplifier. A single PRO5000 delivering 4 ohm rated
power will heavily load a typical 15 amp circuit. Multiple
amplifiers will need to be connected to a circuit capable of
delivering the required current (see specifications), in order
for the amplifiers to produce the expected audio power.
The PRO5000 is normally wired for 12OV 6OHz operation,
as in the USA. The transformer can be rewired to accom-
modate other line voltages upon request. Note that the value
of the internal AC line fuse (near the power switch), should
be changed when converting from lower line voltages
(
12OV or less use a 15 amp Slo-Blo), to higher line voltages
(200V and up use a 7-1/2 amp Slo-Blo). Never wire the
amplifier for a lower line voltage than what is supplied in an
attempt to obtain greater output power. Such an attempt will
very likely damage parts in the amplifier not rated for the
higher voltages that will result, and the warranty will be
voided.
A 3-wire grounded power cord is supplied. It must be
connected to a properly grounded (earthed) AC receptacle
for safety. Do not break off the ground pin on the plug to
avoid using the proper adapter for 2-wire receptacles.
SIGNAL INPUT:
Both 1/4” phone and XLR balanced connectors are pro-
vided on the back panel. These connectors are wired in
parallel for each channel, so that either may be used with no
further switching. The unused connector may be used to
“daisy chain” other amplifiers from the same source using
the appropriate cables.
To achieve maximum noise rejection, balanced lines should
be used for the inputs (two out-of-phase polarity signal
conductors plus a ground shield). The XLR connectors are
wired for the IEC international standard, which connects
the #1 pin to the ground shield; the #2 pin as the non-
inverting or ‘hot’ signal; and the #3 pin as the inverting or
‘return’ signal. The phone jacks are wired with the sleeve
as the ground shield; the tip as the non-inverting signal; and
the ring as the inverting signal. Note that in other equip-
ment the two signal connectors are sometimes interchanged
from what is stated here-it is therefore wise to check for
consistency among the equipment being installed.
For an unbalanced input line (one signal conductor and a
ground shield), connect the signal conductor to the non-
inverting input, and connect the ground shield to the input
ground AND the inverting input of the amplifier. Note that
with a two conductor 1/4” phone jack, this connection is
automatically made, assuming that the sleeve (which is
longer than that of a three circuit phone jack and includes
the ring) is the ground shield and the tip is the signal. In this
case, simply insert the phone jack fully into the input of the
amplifier.
For bridged mono operation, only use the channel A input
and set the mono/stereo switch to mono. Make no connec-
tion to the channel B input jacks. In this mode the channel
A gain control determines the gain of the amplifier. See
below for a description of loudspeaker connection in this
mode.
To prevent noise or hum, it is essential that all input
connections are secure, and that the cables are not frayed or
loosely connected to the plug.
OUTPUT:
The red and black binding posts will accept a variety of
speaker lead terminations, the most convenient of which
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