Bosch PRA-AD604 Amplifier, 600W 4-Channel Amplifier

The Bosch PRA-AD604 is a flexible and compact multi‑channel power amplifier for 100V or 70V 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 Bosch PRA-AD604 amplifier channel adapts to the connected loudspeaker load, is only limited by the total power budget of the whole amplifier. This flexibility, and the integration of a spare amplifier channel, make it possible to utilize the available power effectively and use fewer 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.

Efficient 4-Channel Power Amplifier

• Transformerless, galvanically isolated, 70/100V outputs, with a total loudspeaker output power of 600W.
• 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.
• Cost and space-saving, an integrated, independent spare channel for fail‑safe redundancy.
• High efficiency in all operating conditions; dissipation and heat loss are 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 is 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.