Sennheiser ACA 3 – 2x4:1 Active Antenna Combiner

Product Overview

The Sennheiser ACA 3 is a rack-mount 2 x 4:1 active antenna combiner for distributing RF to analog and digital Sennheiser wireless stationary receivers. This active antenna combiner supports distributed antenna systems for multi-room wireless microphone coverage in large venues. It operates across 470 to 798 MHz and is compatible with all analog and digital Sennheiser stationary receivers in that range. AV integrators deploy it to feed multiple receivers from a shared antenna front end in broadcast, worship, and large-venue installations.

Product Description

The ACA 3 is a 1U, 19-inch rack-mount unit that combines antenna signals at unity gain to drive banks of Sennheiser wireless receivers. It is engineered for zone and distributed antenna systems where wireless microphone coverage must span multiple rooms, large halls, or complex sites. The combiner provides 0 dB gain (within +/-3 dB across 470-790 MHz), so it distributes RF without altering signal level, preserving the link budget across the antenna network.

Each of the eight antenna inputs offers switchable DC power for head amps or active antennas such as the AB 3, AB 3700, A12AD, and AB 9000, and RF from each input is switchable to isolate unused antennas. Front-panel LEDs indicate input state, including RF present, DC on, and DC current overload, which helps integrators diagnose a faulty or short-circuited antenna cable during commissioning. Connections are made over BNC connectors, the standard for professional RF distribution. The unit outputs 12 V at up to 250 mA with overload protection for powered antenna components. It ships with the ACA 3 and three mains cables (EU, UK, and US) for international deployment. Backed by a 2-year warranty, the ACA 3 is a core building block for scalable wireless microphone infrastructure in large churches, broadcast facilities, and outdoor event sites.

Key Features

• 2 x 4:1 Combining at Unity Gain — The combiner merges antenna signals at 0 dB gain to feed banks of receivers without altering signal level.
• Broad Frequency Range — It supports 470 to 798 MHz, covering the tuning ranges of analog and digital Sennheiser stationary receivers.
• Switchable DC on Each Input — Each antenna input can supply DC power for head amps or active antennas such as the AB 3, AB 3700, A12AD, and AB 9000.
• RF Input Isolation — RF from each of the eight antenna inputs is switchable, letting integrators isolate unused antennas.
• Diagnostic LED Indicators — Front-panel LEDs show RF present, DC on, and DC current overload to flag faulty antenna cabling.
• BNC Connectivity — Standard BNC connectors integrate the unit into professional RF distribution infrastructure.
• 1U Rack-Mount Chassis — The 19-inch, 1U form factor installs cleanly into a standard equipment rack.
• International Power Cables — The unit ships with EU, UK, and US mains cables for deployment across regions.

Typical Applications

• House of worship campuses with multi-room wireless coverage
• Broadcast studio and facility RF distribution
• Auditorium and large-venue wireless microphone systems
• Multi-purpose rooms and commercial meeting spaces with zoned coverage
• Government spaces requiring distributed wireless infrastructure

Technical Specifications

Frequently Asked Questions

Which receivers is the ACA 3 compatible with?

The ACA 3 works with all analog and digital Sennheiser wireless stationary receivers operating in the 470 to 798 MHz range. Confirm your receiver tuning range falls within this band.

How does the ACA 3 fit into a distributed antenna system?

It combines antenna signals at unity gain and distributes RF to multiple receivers, enabling zone or multi-room wireless microphone coverage from a shared antenna front end.

Can it power active antennas?

Yes. Each antenna input offers switchable DC power for head amps and active antennas such as the AB 3, AB 3700, A12AD, and AB 9000, with a 12 V, 250 mA overload-protected output.

How is it installed in a rack?

The ACA 3 is a 1U, 19-inch rack-mount unit that installs into a standard equipment rack alongside receivers and other RF distribution gear.

What connectors does it use?

It uses BNC connectors on its antenna inputs and outputs, the standard for professional RF distribution cabling.

How do I troubleshoot a faulty antenna cable?

Front-panel LEDs indicate RF present, DC on, and DC current overload. A current overload indication can flag a shorted or faulty antenna cable during commissioning.

What warranty and support are included?

The ACA 3 carries a 2-year manufacturer warranty. For system design and integration support, contact Creation Networks at https://creationnetworks.net.