Bosch PRA-AD604 Datasheet
Communications Systems | PRA-AD604 Amplifier, 600W 4-channel
PRA-AD604 Amplifier, 600W 4-channel
www.boschsecurity.com
u Flexible power partitioning across all channels
u Low power consumption and heat loss
u Full supervision with integrated fail‑safe redundancy
This is a flexible and compact multi‑channel power
amplifier for 100 V or 70 V loudspeaker systems in
Public Address and Voice Alarm applications. It fits in
centralized system topologies, but also supports
decentralized system topologies because of its
OMNEO IP‑network connection, combined with
DC‑power from a multifunction power supply.
The output power of each amplifier channel adapts to
the connected loudspeaker load, only limited by the
total power budget of the whole amplifier. This
flexibility, and the integration of a spare amplifier
channel, makes it possible to utilize the available
power effectively and use less amplifiers for the same
loudspeaker load, compared to using traditional
amplifiers.
Digital sound processing and control, adjusted to the
acoustics and requirements of each zone, allow for
better sound quality and speech intelligibility.
Functions
Efficient 4‑channel power amplifier
• Transformerless, galvanically isolated, 70/100 V
outputs, with a total loudspeaker output power of
600 W.
• Flexible partitioning of the available output power
across all amplifier channels to use it effectively,
significantly reducing the amount of required
amplifier power in a system.
u Digital signal processing per channel
u IP‑networked on OMNEO for audio and control
• Cost and space saving, integrated, independent spare
channel for fail‑safe redundancy.
• Class D amplifier channels with two-level power lines
for high‑efficiency in all operating conditions;
dissipation and heat loss is minimized to save on
energy and battery capacity for backup power.
Flexibility in loudspeaker topologies
• A/B outputs on every amplifier channel to support
redundant loudspeaker wiring topologies. Both
outputs are individually supervised and disabled in
case of a fault.
• Class A loop wiring possible between the A and B
loudspeaker outputs. Dedicated connection facility
for an end‑of‑line device to supervise the complete
loop, including the B‑output connection.
• Load independent frequency response; the amplifier
channels can be used with any loudspeaker load up
to the maximum, without any change in audio quality.
Sound quality
• Audio‑over‑IP, using OMNEO, the Bosch high‑quality
digital audio interface, compatible with Dante and
AES67; audio sample rate is 48 kHz with 24‑bit
sample size.
• Large signal to noise ratio, wide audio bandwidth and
very low distortion and crosstalk.
• Digital signal processing on all amplifier channels,
including equalization, limiting and delay, to optimize
and tailor the sound in each loudspeaker zone.
1 A
1 B
1
2
3
4
2 A
2 B
3 A
3 B
4 A
4 B
1
2
3
4
A
B
2
1
2 | PRA-AD604 Amplifier, 600W 4-channel
Supervision
• Supervision of amplifier operation and all of its
connections; faults are reported to the system
controller and logged.
• Loudspeaker line integrity supervision without
interruption of audio, using end‑of‑line devices
(separately available) for best reliability.
• Network link supervision.
Fault tolerance
• Dual OMNEO network connections, supporting Rapid
Spanning Tree Protocol (RSTP), for loop-through
connections to adjacent devices.
• Dual 48 VDC inputs with polarity reversal protection,
each with a full power DC/DC converter, operating in
tandem for redundancy.
• Fully independent amplifier channels; the integrated
spare channel automatically replaces a failing
channel, with due regard of the actual sound
processing settings.
• All amplifier channels support two independent
loudspeaker groups, A and B, enabling redundant
loudspeaker wiring topologies.
• Backup analog audio lifeline input driving the spare
amplifier channel to serve all connected loudspeaker
zones in case both network connections, or the
amplifier network interface, would fail.
Connection and functional diagram
DC to DC converter Audio processing (DSP)
OMNEO network switch Controller
Lifeline control interface Lifeline supply input
Lifeline audio input 1‑4 Amplifier channel
Spare channel
Loading...