Toa APH-20 Operating instructions

M del APH-20
20 Watt Amplified Horn
oudspeaker
Installation and
Operating Instructions
APH-20
In association with
MADE IN TAIWAN
www.toa.eu
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SAFETY PRECAUTIONS
• Use only a power supply with the specified output voltage and
current, as exceeding the specified limits could result in fire or other
failures.
• Install the unit only in a location that can structurally support the
weight of the unit and the mounting bracket. Doing otherwise may
result in the unit falling down and causing personal injury and/or
property damage. Be sure to mount the bracket securely, using
appropriate fixings.
• Avoid mounting the unit in locations exposed to constant vibration.
The mounting bracket could be damaged by excessive vibration,
potentially causing the speaker to fall, which could result in personal
injury.
• Do not operate the unit for an extended period of time with the
sound distorting. This is an indication of an overloaded amplifier,
which in turn could cause heat to generate and result in failure of
the unit, or possibly even a fire.
SYSTEM OVERVIEW
This amplified horn loudspeaker is designed and manufactured for
heavy-duty industrial use. It is made from ABS resin, and is supplied
complete with aluminum, universal “U” bracket, which allows for
both horizontal and vertical angular adjustment.
The input is transformer balanced, which eliminates Ground-loop
hum while also providing isolation of at least 500V DC. It has a
built-in 20 Watt power amplifier, which utilises the latest Class “D”
technology.
The unit’s master gain may be set to 12, 18, 24 or 36db by means of
an internal switch. There is also an internal volume control for
on-site adjustment. This is factory pre-set for the purpose of initial
uniformity.
The audio input is factory set to “Balanced”, although unbalanced
signals may be used, and an internal selector jumper is provided to
allow for either. In “Balanced” mode, the audio input of the unit is
transformer isolated. This prevents “Ground-loop hum” and also
provides isolation from the cable of up to 500 Volts DC.
The unit has switchable gains of 12,18, 24 and 36db and is suit-
able for signal level 1V p-p@1K (for Maximum Amplifier output)
The loudspeaker’s frequency response, dynamic range and
dispersion pattern are optimised for the transmission of human
speech.
The unit is weatherproof to IP65 rating. If the unit is disassembled
during installation or servicing, care must be taken to ensure that
glands and gaskets are correctly refitted.
The unit is supplied with a 2 metre flying lead. This is a shielded,
2 - pair type cable. During final termination, do ensure that the
wiring connections are protected from the ingress of moisture.
If the wire terminations are not adequately protected, premature
failure of this unit, or other associated equipment is almost certain.
This unit will operate with a regulated supply Voltage of 12 Volts
DC/2A.
2 3
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INSTALLATION
The unit should be mounted where required by means of the
supplied stainless steel “U” bracket.
Mounting Bracket Dimensions (mm) Front View
IMPORTANT NOTE: If the power adapter is not weatherproof.
It should be mounted in a dry area, no more than 10 metres away
from the loudspeaker unit.
Ensure that the chosen termination method is waterproof!
The connections are as follows:-
BALANCED-LINE INSTALLATION
Wire Colour Connect To
RED +12VDC
B ACK 0VDC
WHITE Audio Signal HOT
GREEN Audio Signal CO D
SHIE D Do not connect (Earth at signal SOURCE end)
UNBALANCED INSTALLATION
Wire Colour Connect To
RED +12VDC
B ACK 0VDC
WHITE Audio Cable Signal Core
GREEN oop to SHIE D
SHIE D Audio Cable Screen
CONNECTION DETAILS
4 5
Default setting from factory
IMPORTANT NOTE: Ensure that the link “JP101” on PCB inside loudspeaker unit is OPEN
Connect sheilds of both cables and insert wire loop between shield and Green wire from loudspeaker
unit as shown above OR connect link “JP101” on PCB inside loudspeaker unit
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When the system is fully operational, you should adjust the gain of
the amplifier module, and/or the volume control, to give the ideal
output level. The gain and volume controls are on the PCB inside
the back cover of the loudspeaker unit, these should be set during
commissioning, using the audio from the system’s source device.
Remove the three screws which hold the rear cover in place (shown
on the right). Carefully remove the cover.
Take note not to lose the screws or gasket
and do not pull on the internal wiring.
To Set the Gain and volume level of the
amplifier module.
1/ Remove the back cover of the loudspeaker.
On the PCB inside there is a 2-way
DIP switch marked “SW1” (Gain).
Set both of these switches to “ON”.
This sets the module to minimum
gain (12db).
2/ Adjust the volume control (anti-clockwise for volume down or
clockwise for volume up) until the output level is adequate. If the
output level is insufficient, set the gain to the next highest gain,
according to the following table, and repeat the procedure with the
volume control.
This may be done at all gain settings, until an adequate output level
is just achieved. Setting the gain to the minimum required will
minimise any unwanted noise pickup.
Now replace the rear cover. As this speaker unit is weatherproof to
IP65, care must be taken during the replacement of the back cover,
to ensure that glands and gaskets are correctly refitted and
watertight.
6 7
Rear View
OPTIONAL EXTRAS
Optional Power supply:
12 VDC 2amp.
Pr duct c de: PS-APH
(none weatherproof)
Optional IEC ead:
Pr duct c de: SKT-IEC-S5000
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