Williams AV FM 558 – FM+ Dual FM/Wi-Fi System, 4 Receivers

Product Overview

The Williams AV FM 558 is a turnkey assistive listening system that combines the FM+ C transmitter with four PPA R38N receivers for small venues. The transmitter broadcasts simultaneously over FM (72.1–75.9 MHz) and the facility's Wi-Fi network, giving classrooms, courtrooms, boardrooms, and small worship spaces an ADA-ready hearing assistance solution that also supports smartphone listening through the WaveCAST app. As the entry point to the FM 558 family, this base package suits venues that already have antennas, rack hardware, and chargers or plan to specify them separately.

Product Description

The FM+ C transmitter streams real-time audio to both FM receivers and Wi-Fi devices from one half-rack chassis. Seventeen selectable wideband channels in the 72 MHz band allow multiple systems to coexist in one building — useful for multi-channel interpretation or adjacent rooms — and FM range reaches up to 1,000 feet with a compatible remote antenna such as the Williams AV ANT 005. The combination XLR/1/4-inch TRS input accepts balanced or unbalanced microphone or line-level sources with selectable phantom power, while DSP processing applies selectable compression and filtering to keep speech intelligible for hearing-impaired listeners. Configuration runs through the 3.12-inch OLED front panel or the hosted web page over Ethernet, and the transmitter integrates with third-party room control systems for managed AV environments.

The four included PPA R38N receivers are handheld body-pack units with 1-inch OLED displays, menu-driven tuning, channel lock, and detachable belt clips. They run approximately 50 hours on two AA alkaline batteries or 32 hours on NiMH rechargeables, with bottom charging contacts compatible with Williams AV CHG-series drop-in chargers. Audio outputs through a 3.5 mm stereo jack supporting earphones, headphones, or neckloops for telecoil hearing aid users, and the Wi-Fi stream places no cap on the number of app-based listeners.

For a fully accessorized deployment with antenna, chargers, neckloops, rack kit, and ADA signage included, step up to the FM 558 PRO package, or compare every configuration in the Williams AV collection at Creation Networks.

Key Features

• FM and Wi-Fi in One Transmitter — The FM+ C broadcasts to dedicated receivers and streams to the WaveCAST app simultaneously, serving every listener type.
• Four R38N OLED Receivers — Handheld receivers provide menu-based access to 17 wideband channels with channel lock and bright OLED displays.
• 17 Selectable Channels — Multiple FM 558 systems can operate in the same facility for interpretation channels or adjacent rooms.
• DSP Speech Processing — Selectable compression and high-pass/low-pass filtering optimize clarity for assistive listening feeds.
• Pro Analog Input — The XLR/TRS combo jack handles mic or line sources, balanced or unbalanced, with selectable phantom power.
• Unlimited Wi-Fi Listeners — App-based streaming over the venue network scales capacity beyond the included receivers at no added hardware cost.
• Half-Rack Form Factor — The 1RU, half-width chassis mounts in standard 19-inch racks with optional RPK 005 or RPK 006 kits.
• Long Receiver Battery Life — Up to 50 hours on alkaline or 32 hours on NiMH batteries keeps receivers in service across multiple events.

Typical Applications

• Conference room
• Boardroom
• Training room
• Government space
• House of worship
• Multi-purpose room
• Commercial meeting space

Technical Specifications

Frequently Asked Questions

What is included in the FM 558 base package?

The FM+ C dual FM and Wi-Fi transmitter and four PPA R38N receivers. Antennas, rack kits, chargers, neckloops, and ADA signage are available separately or bundled in the FM 558 PRO package.

Do I need an antenna?

Yes. The FCC requires this transmitter to operate with approved FCC 15.203 compliant antennas — ANT 005, ANT 021, ANT 024, or ANT 025 — and to be professionally installed.

How does Wi-Fi listening work?

The transmitter connects via Ethernet to the venue's existing Wi-Fi network and streams audio to the WaveCAST app on listeners' own devices. It does not create its own wireless network.

Can hearing aid users connect to the receivers?

Yes. The R38N's 3.5 mm stereo jack accepts neckloops such as the Williams AV NKL 001, which couple inductively to telecoil-equipped hearing aids and cochlear implants.

Can I run multiple systems in one building?

Yes. With 17 selectable wideband channels, several FM 558 transmitters can operate simultaneously for interpretation channels or separate rooms without interference.

What warranty comes with the system?

The transmitter carries a 2-year parts and labor warranty; the R38N receivers carry a Lifetime PLUS Limited Warranty, with 90 days on most accessories.