ST-CX2S

RDL ST-CX2S - Subwoofer Crossover Filter

The RDL ST-CX2S is an active subwoofer crossover filter from the STICK-ON® series, designed for precise low-frequency signal processing in professional audio systems. It extracts and equalizes subbass content from a stereo source, providing optimal signal conditioning for subwoofer amplifiers and speakers.

The module features two separate, isolated high-impedance balanced inputs, which can also be wired unbalanced. The 150Ω balanced output can drive both low- and high-impedance balanced or unbalanced lines. The unit operates at unity gain at 63Hz, with a BOOST control allowing up to +5.5dB gain at 3 Hz.

The ST-CX2S includes RDL’s SupplyFlex™ power input configuration, supporting ground-referenced, floating, or bipolar 24V DC power sources.

Functionality

• Active subwoofer signal separation and equalization
• Extracts subbass from stereo sources
• Adjustable low-frequency BOOST control
• High isolation and low distortion
• Supports balanced and unbalanced connections
• Compact STICK-ON form factor for easy AV integration
• SupplyFlex™ power input - compatible with various 24V DC types

Features

• Inputs: 2 x 50 kΩ balanced line-level (+4 dBu)
• Output: 150Ω balanced line-level (+4 dBu)
• Output bandwidth: 22 Hz - 80 Hz (adjustable BOOST)
• High-frequency attenuation: > 45 dB at 400 Hz
• Gain: Unity at 63 Hz; adjustable up to +5.5 dB at 32 Hz
• Headroom: ≥ 18 dB at 30 Hz (max BOOST), typically 22 dB
• THD+N: < 0.05%
• CMRR: > 60 dB (30 Hz and above)
• Residual noise: < -90 dB (ref. +4 dBu), typically -95 dB
• Operating temperature: 0°C to 55°C
• Power: 24V DC, 30 mA (ground-referenced or floating)

The RDL ST-CX2S is a reliable and flexible solution for AV integrators who require precise subwoofer signal processing. It’s ideal for commercial, educational, and entertainment installations where low-frequency control is essential.