The FM+ C integrates professional WaveCAST Wi-Fi audio server technology into a Williams AV FM assistive listening system and integrates with third-party room systems. AV professionals can control third-party room systems with Telnet commands via Ethernet and end users can listen with either an FM receiver or with their own smartphone (via the WaveCAST Receiver App). Along with this flexibility comes exceptional audio quality, as the FM+ C is built on a professional digital audio (DSP) platform.
The FM+ C is designed to support those who want to use their own smartphones and headphones for a more discreet assistive listening experience. Simplicity is also available for those who want a more traditional assistive listening system with a dedicated FM receiver and headset. Venues no longer need to choose between providing FM or Wi-Fi assistive listening systems. FM+ C supports both the new iOS and Android WaveCAST Receiver Apps — in addition to all of the current and legacy Williams Sound FM receivers operating on the 72-76 MHz bandwidth.
Most settings can be changed via the front panel interface, or the hosted web interface. A remote programming guide is available upon request.
The FM+ C uses the WaveCAST app to provide an easy-to-use, intuitive user interface. It is available in iOS or Android. Listeners easily select channel and volume level once their personal device is connected to the Wi-Fi network. The app does not work on FM Broadcasts.
8.45” W x 8.25” D x 1.72”H (21.5 cm x 21 cm x 4.4 cm)
Transmitter: 3.2 lbs (1.45 kg)
Standard 19” Rack, one EIA rack space high, 1/2 space wide
1-2 units can be mounted in a single rack space with optional RPK 005 (single) or RPK 006 (double) Rack Mount Kits
Desktop Style Transformer (TFP 062); Input: 100-240 VAC, 50/60 Hz. IEC Line Cord; Output: 24 VDC, 750 mA, 18W. 2.5mm ID center positive barrel connector
Power ON Indicator
Push On/Push Off latching power button with backlight. Green backlight indicates power ON, backlight off indicates power OFF.
Operating: +32° F to +122° F (0° C to 50° C); Storage: -4° F to +158° F (-20° C to 70° C)
1. 3.12” High Resolution OLED display with selections via buttons. 2. Hosted Web page. 3. Telnet commands over ethernet (see our WaveCAST and FM+ Programmers Guide” for available commands and protocol).
RJ-45 on back of unit supports CAT 5e cable lengths up to 328 feet (100 meters); 10/100 Base-T IEEE 802.3 compliant, unique MAC address. RJ-45 jack used for web page and streaming audio out. An external Router/DHCP Server is required to stream audio to receiving devices.
72.1-75.9 MHz , 17 wideband channels (selectable)
+/- 2 ppm stability, 0-50 deg C
+/- 75 kHz maximum
RF Field Strength
Does not exceed 80 mV/m at 3 m
ANT 005, ANT 021, ANT 024, ANT 025, ANT 028, ANT 029, ANT 034
Refer to Williams AV’s Antenna Selection Install Guide for FCC-compliant antennas for this product.
Up to 1000 ft (304 m) with ANT 005 coaxial antenna mounted on rear chassis F-connector
(1x) #10-32 stud connector in center of unit (pcb mounted)
(1x) F-connector on rear chassis
RF Transmit (RF) Power Indicator
1 OLED On Air Indicator with 4 states indicating power level Off, Low, Medium, and Full Power.
RF Time Out (sleep mode)
30 min. duration, 4 hr. duration, or Always On; selected via web page. When audio drops below -18dB, the selected duration begins, and when it expires the unit stops transmitting and goes into a low-power (“sleep”) mode. Any button press or resumption of audio above -18dB “awakens” the unit and it begins transmitting again.
(1x) Combination 3-pin XLR, 1/4” (TRS) jack for balanced or unbalanced line level, or balanced or unbalanced microphone with selectable phantom power. Optional RJ-45 Dante Input (“D” models only).
Audio Processor Functions
DSP based; Compression: 1:1, 1.5:1 or 2:1; High-pass and Low-pass Filter Frequency control, Music, Voice, and Hearing Assistance Audio Presets
31-16000 Hz, +/-3 dB (re: 1 kHz) (“Music” Audio Preset)
64 dB (typical) Transmitted RF @ 1kHz
Total Harmonic Distortion
Less than 0.25% @ 1 kHz (RF output)
Common Mode Rejection
Greater than 57 dB @ 1 kHz, Mic or Line mode
Audio Input Gain Adjust
Adjustable from +24dB to -60 dB, in 1dB steps from front screen or web page
14.4 VDC applied through 2.2 kOhms resistors to analog combo jack: Pin 2 and Pin 3 on XLR jack, or tip and ring on 1/4” TRS jack
Audio Level Display
Front screen bar graph display, each segment representing 3dB. It ranges from -18 (1 segment lit) to +12dB (10 segments lit). Over-range warning is indicated by ‘OLVD’ and flashing empty bar.
1/4” TRS stereo jack, mono signal, 7.8 mW total power with 33 OHM.
Input Level (Bal or Unbal) (at Audio Input Gain = 0dB)
Nominal (@7th Segment Lit): -45 dBV (5.6 mV RMS)
Overload Warning (Displayed on Screen): -20 dBV (100 mV RMS)
Absolute Max. Rating*: +20 dBV (10.0 V RMS)
Nominal (@7th Segment Lit): -8.4 dBV (380 mV RMS)
Overload Warning (Displayed on Screen): +16 dBV (6.5 V RMS)
Absolute Max. Rating*: +20 dBV (10.0 V RMS)
FCC, RoHS3, WEEE, Industry Canada
2-year warranty against component failure and manufacturing defects. See the Full Warranty statement on the website for details.* Stresses above these ratings may cause permanent damage or degrade reliability.
(1) ANT 025 antenna
(1) TFP 062 power supply
(1) WLC 004 line cord