Sennheiser A 9000 A1-A8 Receiving antenna, active, omnidirectional, N-connector, 3/8" mounting thread 470-638 MHz - 504705

Product Overview

The Sennheiser A 9000 A1-A8 is an active omnidirectional receiving antenna purpose-built for Digital 9000 wireless systems operating in the 470–638 MHz (A1-A8) UHF range. It integrates the AB 9000 active booster directly on the antenna body, delivering compensated RF signal to the receiver across long cable runs. The standard N-type RF connector and 3/8" mounting thread allow straightforward installation on microphone stands, truss, or antenna distribution systems.

Product Description

Professional Digital 9000 deployments demand reliable RF distribution across large venues and long cable runs — the A 9000 addresses both challenges in a single compact unit. The integrated AB 9000 booster contains eight highly selective bandpass filters, each passing a discrete 24 MHz window aligned to one of the A1–A8 frequency ranges. This pre-filtering occurs immediately before the first active stage, blocking interference and intermodulation products before they can degrade the signal. The linear RF amplifier compensates for up to 14 dB of coaxial cable loss, allowing the antenna to be positioned remotely from the rack without signal degradation. The receiver and booster work together to measure actual cable loss and automatically adjust gain — eliminating manual level setting. As an omnidirectional (log-periodic hybrid) design, the A 9000 provides wider horizontal coverage than directional antennas, making it well suited to stages and audience areas where transmitter position is unpredictable. The active frequency window is remotely selectable from the Digital 9000 receiver, so no physical adjustment is required when changing frequency bands. The N-type RF connector is a professional-grade interface rated for low insertion loss, and the standard 3/8" thread provides a universal mount for existing stands and hardware. At $1,499, the A 9000 is the correct choice for engineers building permanent or touring Digital 9000 infrastructure where RF reliability is non-negotiable.

Key Features

• Active Omnidirectional Design — Integrates the AB 9000 booster on the antenna for wide-area coverage with active gain.
• Eight Selective Bandpass Filters — Each filter passes a 24 MHz window, blocking out-of-band interference directly before the first active component.
• Up to 14 dB Cable Loss Compensation — Linear RF amplifier maintains signal integrity over long coaxial cable runs between antenna and rack.
• Automatic Gain Adjustment — Receiver and booster jointly measure cable loss and set gain automatically, eliminating manual calibration.
• Remote Frequency Window Selection — Active band is selected from the Digital 9000 receiver; no physical adjustment at the antenna required.
• 470–638 MHz Coverage (A1-A8) — Eight discrete 24 MHz sub-bands span the full A1-A8 UHF allocation for multi-frequency deployments.
• N-Type RF Connector — Professional-grade interface with low insertion loss and high durability for touring and installed applications.
• 3/8" Mounting Thread — Universal thread compatible with standard microphone stands, boom arms, and truss mounting hardware.
• Digital 9000 System Integration — Designed exclusively for the Digital 9000 ecosystem, ensuring full compatibility with SKM 9000, SKM 9000 BK, and SK 9000 transmitters.
• Compact Form Factor — Antenna and booster in a single housing reduce cable clutter and simplify deployment.

Typical Applications

• Large-scale live touring productions using multi-channel Digital 9000 systems
• Permanent installed sound in arenas, stadiums, and convention centers
• Broadcast studios and outside broadcast trucks requiring robust UHF antenna infrastructure
• Houses of worship with distributed antenna systems and long cable runs from RF equipment to antenna positions
• Theater productions with complex RF coordination across wide stage areas
• Corporate conference centers with high RF channel counts

Technical Specifications

Frequently Asked Questions

Q: What wireless systems is the A 9000 A1-A8 compatible with?

The A 9000 is designed exclusively for Sennheiser's Digital 9000 series, including the SKM 9000, SKM 9000 BK, and SK 9000 bodypack transmitters paired with the EM 9046 and EM 9046 DX receivers.

Q: What does the A1-A8 designation mean?

A1 through A8 refer to eight discrete 24 MHz sub-bands spanning the 470–638 MHz UHF range. The active bandpass filter in the antenna passes only the selected sub-band window, rejecting signals outside it.

Q: How is the active frequency window selected?

The frequency window is remotely selected from the Digital 9000 receiver over the RF cable — no manual adjustment at the antenna is needed. This is particularly useful when the antenna is mounted in a difficult-to-reach position.

Q: How does the automatic gain control work?

The AB 9000 booster and the Digital 9000 receiver jointly measure the insertion loss of the coaxial cable between them and automatically set the amplifier gain to compensate, up to a maximum of 14 dB.

Q: Can I use the A 9000 with antenna combiners or splitters?

Yes. The N-type connector is standard for professional RF distribution components. It is compatible with Sennheiser's ASA 3715 and similar antenna splitter/combiner units used in multi-channel Digital 9000 installations.

Q: What is the difference between the A 9000 and the AD 9000?

The A 9000 is omnidirectional, providing 360-degree horizontal coverage, which suits stages where transmitters can be anywhere in front of, beside, or behind the antenna. The AD 9000 is directional (log-periodic), offering higher front gain but narrower coverage — typically used for longer-throw front-of-house applications.

Q: Does the A 9000 require external power?

The AB 9000 booster inside the A 9000 is powered via the coaxial cable from the Digital 9000 receiver — no separate power supply or power injector is required.

Q: What mounting hardware is compatible?

The standard 3/8" mounting thread accepts common microphone stand adaptors, boom arm clips, and truss mounting brackets. Most American and European mic stand hardware uses a 5/8"-27 thread, so a standard 3/8"-to-5/8" adaptor will be required for typical stand mounting.