Operating Elements And Connections; Safety Notes; Connecting The Amplifier; Setting Up The Amplifier - Monacor STA-450D Instruction Manual

Digital PA Amplifier
with 4 or 8 Channels
These instructions are intended for users
without any specific technical knowledge .
The speakers, however, should only be con­
nected by persons with the corresponding
technical knowledge . Please read these
instructions carefully prior to operating the
unit and keep them for later reference .
All operating elements and connections
described can be found on the fold­out
page 3 .
1 Operating Elements
and Connections
1 Button MUTE to mute the corresponding
channel
2 Indicator CLIP for each channel
lights up when the channel is overloaded
3 Volume control LEVEL for each channel
4 Switch POWER
5 Balanced inputs as XLR jacks for each
channel; in case of bridge mode, only
connect the odd­numbered input
6 Unbalanced inputs as RCA jacks for each
channel; in case of bridge mode, only
connect the odd­numbered input
7 Switch for the operating mode, one for
each channel pair
NORMAL = each channel operates sepa­
rately
BRIDGE = bridge mode
8 Speaker terminals
9 Support for the mains fuse
Only replace a blown fuse by one of the
same type!
10 Mains jack for connection to a socket
(230 V/ 50 Hz) via the supplied mains cable

2 Safety Notes

The unit corresponds to all relevant directives
of the EU and is therefore marked with
WARNING The unit is supplied with haz­
ardous mains voltage . Leave
servicing to skilled personnel
only and do not insert anything
into the air vents! Inexpert
handling may result in electric
shock .
•
The unit is suitable for indoor use only . Pro­
tect it against dripping water and splash
water, high air humidity, and heat (admis­
sible ambient temperature range 0 – 40 °C) .
•
Do not place any vessels filled with liquid,
e . g . drinking glasses, on the unit .
•
The heat being generated in the unit must
be dissipated by air circulation; never cover
the air vents of the housing .
•
Do not set the unit into operation, and im­
mediately disconnect the mains plug from
the mains socket if
6
1 . there is visible damage to the unit or to
the mains cable,
2 . a defect might have occurred after a drop
or similar accident,
3 . malfunctions occur .
The unit must in any case be repaired by
skilled personnel .
•
Never pull the mains cable to disconnect
the mains plug from the mains socket,
always seize the plug .
•
For cleaning only use a dry, soft cloth, never
use chemicals or water .
•
No guarantee claims for the unit and no
liability for any resulting personal damage
or material damage will be accepted if the
unit is used for other purposes than orig­
inally intended, if it is not correctly con­
nected or operated, or if it is not repaired
in an expert way .
•
Important for U. K. Customers!
The wires in this mains lead are coloured
in accordance with the following code:
green / yellow = earth
blue = neutral
brown = live
As the colours of the wires in the mains
lead of this appliance may not correspond
with the coloured markings identifying the
terminals in your plug, proceed as follows:
1 . The wire which is coloured green and yel­
low must be connected to the terminal in
the plug which is marked with the letter
E or by the earth symbol ⏚, or coloured
green or green and yellow .
2 . The wire which is coloured blue must
be connected to the terminal which is
marked with the letter N or coloured
black .
3 . The wire which is coloured brown must
be connected to the terminal which is
marked with the letter L or coloured red .
Warning – This appliance must be earthed .
If the unit is to be put out of oper­
ation definitively, take it to a local
recycling plant for a disposal which
.
is not harmful to the environment .
3 Applications
This digital amplifier is ideally suited for
simultaneous PA application in several rooms .
For this purpose, model STA­450D is equipped
with four channels, model STA­850D with
eight channels . Each channel is able to deliver
an RMS power of 50 W .
For a higher output power, two channels
each can be bridged . Due to the bridge circuit,
an RMS power of 100 W can be delivered per
channel pair .

4 Setting up the Amplifier

The amplifier is designed for installation into
a rack (482 mm / 19") but can also be used as
a tabletop unit . In order to ensure sufficient
cooling of the amplifier, air must always be
able to flow freely through all air vents .
4.1 Rack installation
For rack installation, the amplifier requires
2 RS (RS = rack space = 44 .45 mm) . To prevent
the rack from becoming top­heavy, insert the
amplifier into the lower section of the rack .
The front plate is not sufficient for fixing the
amplifier safely; additionally use lateral rails or
a bottom plate to secure the amplifier .
The hot air given off by the amplifier must
be dissipated from the rack; otherwise heat
will accumulate in the rack which may not
only damage the amplifier but also other units
in the rack . In case of insufficient heat dissi­
pation, install a ventilation unit into the rack .

5 Connecting the Amplifier

All connections must only be made or
changed with the unit switched off!
1) Connect the signal sources (e . g . CD
player, preamplifier, mixer) to the jacks
INPUT (5, 6) .
The XLR jacks (5) are designed for bal­
anced signals and, for rated power, require
an input signal of 550 mV as a minimum .
Connect signal sources with unbal­
anced signals to the RCA jacks (6) . For
rated power, a signal of 1 V as a minimum
is required .
For channel pairs intended for bridge
mode ( chapter 6 .1), only connect the
☞
odd­numbered input .
2) Connect the speakers to the terminals
OUTPUT (8) . The table on page 3 shows
the required power rating (P
speakers .
For channels operating in normal
mode [switch (7) in position NORMAL],
connect the marked core of the speaker
cable to the red terminal and the other
core to the black terminal . In normal mode,
the highest output power will be reached
with 4 Ω speakers . Speakers with lower
impedance (Z) must not be connected; the
amplifier may be damaged . 8 Ω speakers
may be connected; in this case, the output
power will slightly decrease .
For channel pairs operating in bridge
mode [switch (7) in position BRIDGE],
connect the marked core of the speaker
cable to the left, red terminal of the chan­
nel pair and the other core to the right,
red terminal (see imprint BRIDGE at the
terminals) . In bridge mode, the maximum
output power will be reached with an 8 Ω
speaker . Speakers with lower impedance
(Z) must not be connected; the amplifier
may be damaged . Speakers with higher
impedance may be connected; in this case,
the output power will slightly decrease .
3) First connect the mains cable to the mains
jack (10) and then the mains plug of the
cable to a socket (230 V/ 50 Hz) .
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