AH-5A BOGEN COMMUNICATIONS, AH-5A Datasheet - Page 70

• Manufacturer Part Number: AH-5A
• Description: Amplified Speaker/horn
• Manufacturer: BOGEN COMMUNICATIONS

Specifications of AH-5A

• Peak Reflow Compatible (260 C): No
• Leaded Process Compatible: No
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

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WHY USE SELF-AMPLIFIED TECHNOLOGY?
Convenient System Expansion
Low Signal Levels Prevent Crosstalk
In certain installations it may be desirable to use conductors
in an existing telecommunication cable to deliver paging to dif-
ferent floors or areas in a facility. 70V amplifier signals would
not be appropriate to run in the same cable with analog tele-
phone signals since their high level could cause crosstalk in
the other telephone circuits in the cable. Because the audio
signal levels supplied to the inputs of the amplified speakers
are similar in level to analog telephone levels, there will be no
crosstalk of the paging system in the telephone lines.
The raw 24V DC power needed by the self-amplified speaker
can also be carried in the telecom cable since it contains no
interfering signals, but care must be exercised to make sure
the length of cable will not cause too much voltage to be lost
in the cable. (See Page 75 for more information.)
WHAT IS A SELF-AMPLIFIED SYSTEM?
Self-Amplified Paging Systems
consist of:
• Self-Amplified Speakers
A self-amplified system can be expanded by adding extra speak-
ers and power supplies as required. They are extremely scala-
ble due to the fact that each speaker is an amplifier unto
itself. It is also easy to connect additional power supplies
where needed to power the speakers. In some instances
there may not be sufficient audio signal level available for the
speaker’s input. In these instances, a small buffer can be in-
stalled inline to boost the signal level.
Self-amplified speakers can also be used to expand 70V paging
systems in cases where the added speakers would overload an
existing central 70V amplifier. The same buffer that is used to
boost signal level can be used to reduce the large 70V speaker
signal to a level that is compatible with the input of self-ampli-
fied speakers. A suitable power supply can be located near the
expansion speakers to power their internal amplifiers. This ap-
proach can be used instead of replacing the central 70V ampli-
fier with a larger one to handle the extra speakers.
2 wires supply the low-level audio paging signal to the ampli-
adjust output level.
miniature amplifier that drives the speaker directly. Each
speaker requires 4 wires. Two wires supply the raw 24V DC
voltage to power the speaker’s internal amplifier and another
fier’s input. All amplified speakers contain volume controls to
each contain an individual, built-in,
AUDIO
Self-amplified speakers can be very cost effective in small
systems since they provide scalability in small increments.
The centralized amplifiers in 70V systems are typically avail-
able in set output power level steps that start at 6 or 10 watts
and increment by 10 watts or more from model to next higher
powered model. In small applications that require only a few
watts of paging, the extra power capability of the 70V ampli-
fiers may not be an advantage due to the higher cost associ-
ated with the amplifier’s extra power, especially if it will not be
used in the future.
Self-amplified systems can be designed with much smaller out-
put level power steps so that only the necessary audio power
is installed in the facility. This can result in a lower cost of
equipment especially where the desired power level is con-
siderably less than the smallest applicable 70V amplifier out-
put level.
• A Power Supply
• An Interface Device
Cost Effective for Small Installations
Self-Amplified paging systems are made up of equipment
that consume or provide operating current. To operate
properly, the system needs to provide at least as much
24V current as it consumes.
Each product has a Current Units number. This number is
either positive, negative, or zero to indicate how much cur-
rent it provides to or consumes from the system.
Note: One Current Unit = 50 mA, 24V DC
a telephone level audio paging signal to all the speakers in the
speakers in the system, an interface device may not be needed.)
ground music sources and the telephone system and supplies
system. (Depending on the telephone system and number of
24V DC voltage that will power the amplifier built in to each
self-amplified speaker. Several power supplies can be
located in convenient areas in the facility.
Understanding Current Units
DC POWER
or multiple power supplies provide the raw
that connects the paging system to back-