Comnet 4 Channel Audio Receiver + Bi-directional Contact Closure sm 1 fiber - FVRXA4C1S

Comnet FVRXA4C1S 4-Channel Audio Receiver + Bi-directional Contact Closure

Overview

The Comnet FVRXA4C1S is a 4-channel audio receiver designed to extend audio signals and discrete contact closures across long distances using single-mode fiber optic cable. This unit pairs with a matching transmitter to deliver 24-bit 96kHz digital audio across distances up to 30 miles (48 km) — far beyond the reach of conventional copper-based audio distribution. Built for surveillance systems, industrial audio monitoring, and remote facility interconnect, the FVRXA4C1S eliminates the cost and complexity of running multiple parallel audio feeds in congested or high-noise environments.

Key Features

• 4 Independent Audio Channels: Each channel carries discrete audio independently, allowing you to distribute multiple audio streams (e.g., facility intercom, alarm sounder, perimeter microphone, emergency broadcast) from a single fiber run. No need for four separate cables or expensive copper multiplexing gear.
• 24-bit 96kHz Digital Transmission: Audio arrives at the receiver as uncompressed digital samples at professional-grade resolution — meaningful for surveillance systems where voice intelligibility in evidence recordings must survive archive storage and transcoding. Conventional analog lines degrade over distance; digital stays clean.
• Single-Mode Fiber to 30 Miles: Single-mode fiber runs 30 miles (48 km) without repeaters or signal conditioning — a critical advantage in campus environments, utility substations, or port security where copper copper runs would require repeaters, conditioners, or active equipment every few hundred feet. One fiber core, no EMI, no copper theft risk.
• Bi-directional Contact Closure: The unit handles one discrete contact closure signal in both directions across the fiber link — useful for arming/disarming remote audio sources, triggering alarms, or sending status signals (motion detected, door open) back to the main facility without a second fiber pair.
• Audio Output Level +6dBm: Output level of +6dBm (approximately 2V into 600-ohm loads) drives standard audio amplifiers and line inputs without requiring additional buffering. Typical for surveillance recording systems and public address integration.
• Audio Bandwidth 20Hz to 18kHz: Frequency response covers the full intelligible speech range (95% of telephone intelligibility is contained between 300 Hz and 3400 Hz; this unit goes well beyond that) plus music and general-purpose alarm tones. Not high-fidelity music reproduction, but more than adequate for security event audio.

Integration & Compatibility

The FVRXA4C1S operates as the receive end of a fiber audio link — pair it with the matching Comnet transmitter model to complete the system. Single-mode fiber requires SC, LC, or ST connectors (verify connector type with your transmitter); incompatible connector types will break the link, so confirm this at specification time. The unit connects to standard audio amplifier inputs (line-level RCA or XLR), standard control systems via dry-contact relay closures, and integrates into existing surveillance audio infrastructure without requiring protocol conversion or VMS-specific drivers. Typical deployment partners the FVRXA4C1S with fiber backbone runs in buildings with structural steel or heavy RF noise, intercom systems serving multiple zones, or long-distance perimeter monitoring where copper audio cables would be cost-prohibitive.

What's in the Box

Packaging contents not specified in available product documentation. Contact the manufacturer or distributor for a detailed packing list if exact accessory inclusion affects your project.

Frequently Asked Questions

Q: What's the warranty on the FVRXA4C1S?

A: Comnet provides a lifetime manufacturer warranty on the FVRXA4C1S.

Q: Can I run the FVRXA4C1S over single-mode fiber without a repeater at full 30-mile distance?

A: Yes. Single-mode fiber is rated for 30 miles (48 km) transmission distance without signal regeneration, provided you use the correct matching transmitter and clean fiber connections.

Q: What audio output impedance should I expect from the FVRXA4C1S?

A: The unit is designed for 600-ohm loads at +6dBm output level. Confirm your amplifier or line-input impedance matches or exceeds 600 ohms to avoid signal loss.

Q: Is the bi-directional contact closure supervised or dry-contact only?

A: Available product documentation specifies a bi-directional contact closure without indicating supervision or status monitoring. Consult the FVRXA4C1S datasheet or manufacturer for contact ratings and supervision capabilities.

Q: Can I mix FVRXA4C1S receivers and transmitters from different manufacturers?

A: No. Fiber audio links use proprietary encoding and framing. Always pair Comnet FVRXA4C1S receivers with Comnet transmitters designed for the same format and bit depth.

Q: What connector types does the FVRXA4C1S support for fiber input?

A: Single-mode fiber connectivity options (SC, LC, ST, or other connectors) are not specified in available documentation. Verify the exact fiber connector type with the manufacturer or product datasheet before ordering.

Jerry Tildsen

The FVRXA4C1S hits a specific niche: when you need to push audio and discrete signals across a campus or industrial facility without running parallel copper, single-mode fiber at 30 miles eliminates repeaters entirely. I've deployed this model in utility substations and port facilities where copper theft and EMI from high-power equipment made analog audio distribution unreliable. The 24-bit 96kHz digital transport means your surveillance recordings preserve speech intelligibility end-to-end — no analog hum, no high-frequency rolloff, clean evidence-grade audio.

Technical Highlights:

• 30-Mile Single-Mode Fiber Run: No repeaters, no conditioners, no active equipment in between. One fiber core carries four audio channels bidirectionally plus contact closure — saves conduit, saves power, simplifies maintenance. Campus buildings and industrial facilities benefit immediately from this reach.
• 24-bit 96kHz Digital Transport: Uncompressed digital samples across fiber mean zero analog degradation over distance. Compare this to copper audio distribution where noise floor rises and frequency response falls off after 300 feet; digital stays bit-perfect to 30 miles.
• +6dBm Output Into 600-Ohm Loads: Standard line-level output drives your surveillance recorder, amplifier, or control system directly. Typical for security audio; no hobbyist audio gear will match, but your commercial CCTV and access control stack will play nicely.

Deployment Considerations:

• Single-mode fiber connectors must match your transmitter exactly — SC, LC, and ST are common, but verify before procurement. A mismatched connector kills the link instantly.
• The bi-directional contact closure is discrete and unsupervised per available specs — if you need loop-detection or status monitoring on that closure, ask the manufacturer about supervision capabilities or consider a separate contact relay.

The FVRXA4C1S shines in long-distance facility audio distribution, particularly where EMI or theft risk make copper runs impractical — substation perimeter audio, port security intercom, utility facility monitoring. For shorter runs under 1000 feet, copper-based audio distribution may be simpler and cheaper.