EM Acoustics Launch CS18 & CS15: Advanced Passive Cardioid Subwoofers

EM Acoustics has expanded its low-frequency portfolio with the introduction of the new CS Series cardioid subwoofers. Consisting of the CS18 and CS15, the range has been designed for applications where precise control of low-frequency energy is critical, without the complexity normally associated with cardioid subwoofer systems.

What sets the CS Series apart is its use of highly advanced passive crossover technology. Unlike conventional cardioid designs that rely on multiple amplifier channels and active processing, both CS18 and CS15 are fully passive and require just a single amplifier channel. This delivers genuine cardioid performance with exceptional simplicity, flexibility and reliability in both touring and installed environments.

 

Cardioid control without complexity

At the core of the CS Series is a design brief that demanded passive crossovers capable of matching – or exceeding – the performance of traditional dual-channel, actively processed cardioid systems. The result is impressive. Both models achieve over 20dB of rear rejection, significantly reducing unwanted low-frequency energy behind the system. In practical terms, this means cleaner stages, reduced low-frequency build-up in performance and backstage areas, and a more accurate, controlled overall system response. For theatres, houses of worship, corporate venues and live music environments, this level of control can make a dramatic difference to clarity and consistency.

 

CS18: Compact size, serious output

The CS18 is the larger of the two models and is aimed at medium-scale live music reinforcement, theatre, corporate AV, houses of worship and theme parks. Despite its relatively compact enclosure, it delivers output and pattern control that defy its physical size.

The CS18 combines a front-firing 18-inch high-excursion neodymium driver with a rear-firing 15-inch neodymium driver, each housed in its own rigidly braced acoustic chamber with optimally tuned bass reflex porting. Linked via EM Acoustics’ advanced internal passive crossover, the system produces a highly consistent cardioid pattern that maximises forward output while tightly controlling radiation to the rear and sides.

CS15: Cardioid performance in a smaller format

For applications requiring the same precision in a more compact footprint, the CS15 delivers the CS Series design philosophy in a smaller enclosure. It pairs a front-firing 15-inch driver with a rear-firing 12-inch driver, again using high-linearity neodymium drivers designed to remain consistent even at high excursion.

The result is a subwoofer that offers impressive SPL and rear rejection for its size, making it ideal for smaller live music systems, theatre installations, conference and corporate AV, and spaces where physical footprint is limited but performance expectations remain high.

 

Built for touring and installation

Both CS18 and CS15 are constructed from multi-laminate premium birch plywood and finished in an impact- and weather-resistant textured polyurethane coating. Black and white finishes are available as standard, with RAL colour matching and enhanced weather protection options offered for permanent installations.

Touring-friendly details include flush bar handles, protective skids, stacking recesses and tour-grade castors, while comprehensive rigging options ensure maximum deployment flexibility. M10 threaded rigging points, quick-release flying plates and an M20 pole mount allow the CS Series to be ground-stacked, flown or integrated into more complex system designs with ease.

 

Simple amplification and flexible system design

A key advantage of the CS Series is its straightforward amplification requirement. Each subwoofer needs just one DSP-enabled amplifier channel, capable of delivering 1000–1600W RMS into a 6-ohm load. While EM Acoustics’ Advanced System Amplifiers are recommended for optimal system matching, the CS Series is deliberately amplifier-agnostic. Suitable DSP settings are provided, allowing integration with other DSP-equipped amplifiers or external processing.

The passive design also enables subwoofers and full-range loudspeakers to be driven down a single four-core cable, reducing cabling complexity and speeding up deployment on site.

 

A natural fit within the EM Acoustics ecosystem

Within the wider EM Acoustics range, the CS18 pairs perfectly with medium to large full-range systems such as the Reference Series R8, R10 and R12, EMS-156/159, and the HALO-B line array. The CS15 complements smaller systems including the R6, R8 and R10, as well as the EMS-101X and EMS-126/129, creating scalable, highly controlled solutions across a wide range of applications.

 

Final thoughts 

With the CS Series, EM Acoustics has delivered something genuinely incredible: true cardioid low-frequency control without added system complexity. By combining advanced passive crossover design, high-performance neodymium drive units and practical, tour-ready construction, the CS18 and CS15 offer a compelling solution for engineers and system designers who want precision, power and simplicity in equal measure.

For anyone building modern professional sound systems where control matters as much as output, the new CS Series is a very welcome addition.