Active Three-Pair Sender-Twisted Pair Format-A-XLR mic & stereo phono in-Black

The RDL DB-TPS3A is a black active three-pair sender that places one microphone signal and two line-level signals onto an RDL TP Format-A twisted-pair connection. Its balanced XLR microphone input provides IEC 24 Vdc phantom power, while separate left and right RCA phono inputs accept unbalanced -10 dBV sources. The microphone feeds pair A, the left input feeds pair B, and the right input feeds pair C, using all three Format-A pairs.

Ideal Use Cases

This model is suited to audio installations that need to carry a microphone and a stereo line source through the same Format-A infrastructure. It can accept a balanced microphone at the XLR input while simultaneously handling left and right unbalanced audio from equipment with RCA outputs. The fixed pair assignments keep the signal layout clear: microphone on pair A, left line audio on pair B, and right line audio on pair C.

The DB-TPS3A is particularly useful when remote powering through the twisted-pair cable is preferred. It also accommodates local 24 Vdc power through a detachable terminal block, giving the installer two documented power-connection methods.

Why Choose This Model

The microphone path offers rear-panel selection between 50 dB NORM gain and 63 dB HIGH gain. The supported balanced microphone input range is -45 to -65 dBu, with maximum levels of -28 dBu in NORM gain and -40 dBu in HIGH gain. Each line input is designed for a nominal -10 dBV unbalanced signal, accepts up to +10 dBV, and receives 12 dB of gain.

Studio-quality precision active balanced circuitry is used for the Format-A output. The microphone input has a 1.2 kΩ balanced impedance and IEC 24 Vdc phantom capability, while the left and right line inputs each present a 10 kΩ unbalanced impedance.

Installation and Integration

The DB-TPS3A connects to RDL TP Format-A equipment through the output arrangement documented for the product family. D- and DS-series models use an RJ45 output, while the EM-series version uses a detachable terminal block. Power connections are provided through RJ45 and a detachable terminal block. A blue LED indicates that the module is powered.

Local power can feed connected modules through a fused power path. The stated power requirement is 24 Vdc at 65 mA plus the requirements of connected loads. Recommended power supplies, which are not included, are the PS-24AS for the USA and PS-24AX for international use. The module measures 1.6 inches wide by 4.11 inches high by 1.89 inches deep. The listed minimum mounting-box depth is 2.4 inches for D- and DS-series models and 39 mm for the EM model.

Performance Highlights

The microphone channel has a frequency response of 100 Hz to 30 kHz within ±1 dB and includes an integral low-cut filter specified at -10 dB at 30 Hz. Its THD+N is below 0.1% from 80 Hz to 20 kHz. Noise below +4 dBu is less than -80 dB in NORM gain and less than -70 dB in HIGH gain. Microphone CMRR is greater than 60 dB in HIGH gain and greater than 65 dB in NORM gain from 50 Hz to 150 Hz.

The line channels cover 20 Hz to 50 kHz within ±0.5 dB, with THD+N below 0.05% across that range and noise below +4 dBu of less than -95 dB. Line-to-line crosstalk is specified below 90 dB at 1 kHz and below 75 dB from 20 Hz to 20 kHz. Available headroom above +4 dBu exceeds 18 dB.

What Makes It Different

Rather than dedicating the twisted-pair link to a single source, the DB-TPS3A uses every Format-A pair for three distinct audio channels. It combines a phantom-powered balanced microphone interface, selectable microphone gain, and two independent RCA line inputs in one compact module. Remote powering, a fused local-power feed for connected modules, and a visible power indicator support flexible integration without changing the defined pair assignments.

Final Assessment

The DB-TPS3A provides a clearly organized way to place one microphone and a stereo line source onto RDL TP Format-A cabling. Its combination of balanced XLR input, phantom power, rear-panel gain selection, two -10 dBV RCA inputs, wide line-channel frequency response, and remote or local power options makes it a focused choice for three-channel Format-A signal transport.