Selene + Poseidon

TECHNICAL FOUNDATION

Selene + Poseidon isn’t two separate products sharing a room – it’s a unified 3-way system designed from the ground up to work as one. The EXCore module powers both the Selene coaxial monitors and Poseidon subwoofers, applying coordinated DSP calibration across all four drivers (two coaxials, two subwoofers). What looks like a modular system operates with the precision and coherence of an integrated design.

This generation introduces living calibration – individual driver level corrections that improve over time as our measurement capabilities and algorithms advance. Your system gets better as we get better.

Selene Cabinet Engineering

Selene uses the same aluminum extrusion approach as Terra, just scaled for its compact form factor. Each cabinet is a 7mm flat-wall extrusion with 19mm corner ribbing and integral cross-bracing. Both the front and rear baffles are 12mm solid aluminum, compressed onto the main shell with series gaskets, creating a sandwich assembly that’s clamped together for maximum rigidity.

The entire assembly extrudes front to back, allowing us to compress everything together with substantial force. The result is a cabinet that’s acoustically inert despite its compact size – no resonances, no flexing, nothing that colors what you’re hearing.

Like Terra, it’s not about being small or exotic. It’s about ensuring the cabinet disappears acoustically, regardless of physical dimensions.

Selene Driver Technology & Passive Crossover

Selene uses a 16cm variant of our third-generation coaxial midrange/tweeter architecture. It shares the same motor structure as Terra’s 18cm coax, but the 16cm version is purpose-designed for Selene’s application – slightly longer throw, slightly smaller diaphragm, optimized to work as a standalone surround monitor. Custom TPCD diaphragms, FEA-optimized motor structure, automated fiber placement pushing tweeter breakup above 40kHz, with DSP limiting high-frequency extension to 30kHz for optimal performance.

The challenge with the Selene + Poseidon system was architectural: we needed to power two coaxial monitors and two subwoofers from a single EXCore module with four amplifier channels. That meant using a passive crossover inside each Selene coaxial to split the midrange and tweeter at 3kHz, rather than giving each element its own amplifier channel – something we typically avoid.

So we over-engineered it. Custom 14AWG square-wire inductors with exact impedance matching at the 3kHz crossover point to eliminate the need for zobel networks. End-to-end DCR under 0.3 ohms. Identical filter bank values on both sides, counter-wound to achieve roughly 100dB of magnetic field cancellation. Four 3% tolerance Panasonic polypropylene caps per filter bank in parallel for exceptionally low ESL/ESR. Custom 3D-printed gyroid isolator mounts that prevent ringing and absorb shock.

This passive LR2 crossover is analog – analog necessarily introduces phase shift, so it cannot be zero-phase. But the 16cm driver is small enough that beaming doesn’t start until 4kHz on the midrange, and at LR2 we can phase invert the tweeter to achieve perfect phase tracking. The result is a passive crossover so consistent that the DSP can treat the coaxial effectively as a full-range driver. Unlike typical passive crossovers that tank your damping factor, the extremely low DCR maintains control and precision.

Both Selene coaxials are still measured individually and linearized at the driver level before crossover application, just like Terra. The EXCore DSP then integrates Poseidon via zero-phase LR4 crossover at 150Hz.

Poseidon Driver Technology

Poseidon uses a custom Epique MMAG architecture 16cm subwoofer with 14.7mm of linear excursion in each direction. That’s serious throw from a compact driver – more excursion than the 9″ drivers in our previous generation Pulsars had.

The custom driver delivers 98dB continuous @ 50Hz from a 6.5″ cube enclosure. When integrated with Selene via zero-phase LR4 crossover at 150Hz, the system extends to 50Hz linear with F6 at 35Hz. Think of Poseidon as providing the foundation Selene’s compact form factor can’t physically achieve on its own – the two working together deliver full-range response from a surprisingly small footprint.

Each Poseidon is measured and calibrated individually, then the complete Selene + Poseidon system receives coordinated calibration to ensure seamless integration across all crossover points.

EXCore & System Integration

The EXCore module is essentially Terra’s amplifier and DSP architecture in a compact 2RU half-rack enclosure. It houses the same Hypex NcoreX amplification (NCx252MP and NCx-102EXT modules), Peregrine DSP architecture with ADSP-21569 SHARC+ processor and ESP32 co-processor, and AKM conversion (AK4493SEQ DAC, AK5572EN ADC) that powers Terra.

Four amplifier channels drive the system: one channel per Selene coaxial (post passive crossover), one channel per Poseidon subwoofer. The DSP applies the internal 3kHz passive LR2 crossover within each Selene coaxial, plus zero-phase LR4 digital crossover at 150Hz for low-frequency integration between Selene and Poseidon.

The top panel is a custom PC-GF/PC hybrid material – rigid enough for structural integrity and heat management, but transparent to RF so the internal WiFi antenna can operate without requiring an external antenna protruding from the back.

Living Calibration: Third generation of our proprietary IRC and DSP architecture now allows us to control individual driver level behavior, with discrete, perfectly phase summed corrections for each transducer independently. This means even more perfect phase tracking at crossovers, with zero interpolation necessary from sine sweep measurements – because crossovers are zero-phase (digitally) and each driver is measured individually, phase tracking is perfect, not just measurement perfect.

Each Selene + Poseidon system is individually measured and calibrated. The entire four-driver system is linearized to achieve ±1.5dB frequency response and ±15° phase coherence (30Hz-30kHz). Because every system is calibrated to the same target, any Selene + Poseidon system acts as a matched pair.

The ESP32 co-processor provides periodic remote updates to DSP corrections as our measurement capabilities, data set, and algorithms improve. Your speakers continue to improve as we improve.

WiFi Control Features:

• Over-the-air firmware and calibration updates
• Multi-system sync (for ATMOS configurations)
• Channel mute, sub mute, channel solo
• Scene/configuration presets
• Delay compensation
• Equalization
• Input sensitivity control
• Boundary control
• Low latency mode