Line-Level Sender/Receiver-4 Twisted Pair Format-A Input & 4 Output Sections-12 Audio Channels

Ideal Use Cases

The RDL SF-TPRS12A is designed for professional audio systems that need to send and receive multiple line-level signals using RDL TP Format-A connections. Four separate three-pair sender sections accommodate 12 balanced audio inputs, while four separate three-pair receiver sections provide 12 balanced audio outputs. Together, these sections support up to 24 audio channels: 12 sender channels and 12 receiver channels.

This configuration is suited to installations requiring centralized access to several balanced sources and destinations. Each section uses all three Format-A signal pairs—A, B, and C—making efficient use of every associated RJ45 connection. Nominal +4 dBu operation matches common professional line-level audio environments.

Why Choose This Model

The SF-TPRS12A places both Format-A sending and receiving functions in one model. The sender side accepts twelve 20 kΩ balanced inputs through detachable terminal blocks and converts them to RDL TP Format-A signals. The receiver side accepts four RDL Format-A inputs through RJ45 connections and delivers twelve 150-ohm balanced outputs on local detachable terminal blocks.

Studio-quality precision active balanced circuitry supports demanding audio distribution applications. The unit also provides local power to modules connected through its RJ45 ports. A green LED for each section indicates the validity of module remote power, giving installers an immediate visual reference during setup and operation.

Installation and Integration

Local audio wiring is handled with detachable terminal blocks, allowing balanced input and output connections to be prepared and serviced without permanently attaching wiring to the unit. Format-A transport connections use RJ45 ports. Each sender section carries signal pairs A, B, and C, while each receiver RJ45 input supplies three corresponding output channels.

Power can be connected through either the dc power jack or a detachable terminal block. The power requirement is 24 Vdc at 400 mA plus connected loads, with a stated maximum of 1.6 A. Recommended power-supply references include the PS-24V3A for the USA, PS-24V3 for international use, PS-24KS for the USA, and PS-24KX for international use.

Automatic-resetting fuse protection guards against wiring faults in connected power circuits. The operating range is 0° C to 55° C. Physical dimensions are 8.74 inches wide, 1.68 inches high, and 5.78 inches deep, or 22.2 by 4.27 by 14.68 centimeters.

Performance Highlights

The audio circuitry offers a frequency response of 10 Hz to 50 kHz within ±0.1 dB. THD+N is specified at less than 0.005%, while crosstalk is listed at less than 85 dB from 20 Hz to 20 kHz. Headroom above +4 dBu is greater than 18 dB, and common-mode rejection is greater than 60 dB from 50 Hz to 150 Hz.

Balanced sender inputs operate at +4 dBu nominal and accept levels up to +22 dBu. The twelve balanced receiver outputs are also rated for +4 dBu nominal operation with a +22 dBu maximum level. The listed noise-below-+4-dBu specification is less than 90 dB.

What Makes It Different

The distinguishing feature of the SF-TPRS12A is its symmetrical collection of four three-pair sender sections and four three-pair receiver sections. Rather than dedicating the unit solely to one transmission direction, it provides twelve channels in each direction. All three Format-A pairs are used per section, combining the three audio paths associated with each RJ45 connection with local balanced terminal-block access.

Per-section remote-power indication, connected-module power distribution, dual power-connection options, and automatic-resetting wiring-fault protection address practical integration needs alongside the audio functions.

Final Assessment

The RDL SF-TPRS12A is a line-level Format-A interface for installations requiring substantial bidirectional audio capacity. Its four sender and four receiver sections support up to 24 total channels, with professional +4 dBu balanced connections on detachable terminal blocks and Format-A transport over RJ45. Wide frequency response, low specified distortion, substantial headroom, local power distribution, fault protection, and section-level status LEDs provide a focused combination of audio performance and installation utility.