Crown DC-300A - 4.3 OUTPUT CIRCUITRY; 4.4 PROTECTION CIRCUITS; 4.5 LVA, LVA CURRENT SOURCE AND BIAS SERVO CIRCUITS; 4.6 INPUT CIRCUITRY

2.1 UNPACKING
As soon as the amplifier shipment is received, please
inspect for any damage incurred in transit. Since the unit
was carefully inspected and tested at the factory, it left
the factory unmarred. If damage is found, notify the
transportation company immediately. Only the consignee
may institute a claim with the carrier for damage during
shipment. However, CROWN will cooperate fully in such
an event. Be sure to save the carton as evidence of dam-
age for the shipper’s inspection.
Even if the unit arrived in perfect condition — as most do —
it is advantageous to save the packing materials. They
will prove valuable in preventing damage should there
ever be occasion to transport or ship the unit. Note
the carton and internal pack — each is designed for pro-
tection during transit, particularly of the power trans-
former weighing over 25 Ibs. Do not ship the unit without
this factory pack!
Be sure to return the warranty registration form to the
factory within ten days for the full warranty coverage.
2.2} MOUNTING
The DC-300A is designed on a standard 19 inch rack-
mounting format. However, it may be custom mounted
if sufficient support is provided. For dimensions see
Fig. 2-1. In any circumstance, sufficient ventilation must
be provided for the unit. Good ventilation practice allows
air to flow completely under, around, and through the
amplifier. If the unit is placed above a horizontal surface,
I
FIG. 2-1
MOUNTING DIMENSIONS
11
Section 2
INSTALLATION
an air space should be allowed above and below the unit.
If sufficient ventilation is not provided, the unit will
intermittently turn off due to the built-in thermal pro-
tection. Such a condition (if observed) will also be ac-
companied by a warm front-panel due to the integral
heat-sinking employed in the amplifier.
Applications requiring long sustained signals at high
power levels may require the use of a cooling fan.
2.3 NORMAL HI-FI INSTALLATION
1. Remove output covers, exposing dua! binding-posts.
Two-conductor speaker cables must connect to the OUT-
PUTS using terminal lugs, tinned ends, or the special
“banana” plugs supplied with the DC-300A. Connect the
in-line fuses as recommended in the Accessory Bag and
Fig. 2-2 Overleaf. (Not needed with CROWN speakers.)
2. Since the DC-300A is a “basic amplifier,’ the main
outputs of the control-center or ‘‘preamplifier’’ must be
connected via shielded audio-cables to the two jacks
marked INPUT. Use RCA-pin at preamp and standard
Y% inch phone-plug at the DC-300A.
The two cables should be tied paralle! along their entire
length, using the accessory cable ties.
3. U/L requirements specify a 3-wire AC power con-
nector; however, proper connections to a switched outlet
on the control center require the use of a 3-to-2 wire
adapter. NOW, plug the AC into a switched outlet on the
control center.
4. Your Control Center may now be turned on. Then
advance the DC-300A Input-Gain Controls about “%-open
(150° clockwise).
When using the CROWN IC-150 Control-Center, the
LOUDNESS should attain almost full rotation (2 to 4
o'clock) for loudest ‘‘concert-hall’’ volume. If at 3
o'clock the volume is low, increase the DC-300A input
gain controls; if too high, decrease the DC-300A gains.
To assure maximum enjoyment and full speaker protec-
tion, read the following detailed sections on OUTPUTS,
INPUTS and Chapter 3— OPERATION.
N
2
4)
a
>
i
—
>
a
e)
2