Estelon Forza Ultra Debuts With Custom Accuton Drivers and Four-Way Design

Estelon has introduced the Forza Ultra, a passive four-way floorstanding loudspeaker that builds on the original Forza launched in 2019. The new model brings technology derived from the Estonian company’s flagship platform, including newly developed Accuton drivers, revised crossover networks and a more direct internal signal path.

A new four-way driver system

The Forza Ultra uses six custom Accuton drivers in a closed-box, four-way configuration. Bass is handled by two 250 mm long-throw aluminum dome woofers with neodymium motor systems. Their low position is intended to transfer bass energy efficiently into the room.

Estelon’s Symmetric Driver Loading arrangement gives both woofers the same acoustic loading so that they operate together. The company says this approach is designed to improve low-frequency definition, power and control. The specified frequency range extends from 27 Hz to 60 kHz, with linear response stated up to 33 kHz.

A custom 190 mm midwoofer and 90 mm midrange driver introduce Accuton’s Crystalid diaphragm technology to the Forza platform. The material combines high stiffness with low moving mass, with the design targeting fast transient behavior and low distortion across the vocal and instrumental frequency ranges.

High frequencies come from Accuton’s latest 25 mm diamond tweeter. It incorporates a revised surround and a multi-cavity rear chamber, with extension specified to 60 kHz. Crossover points are set at 90 Hz, 800 Hz and 2.5 kHz.

Redesigned crossover and shorter signal paths

Estelon has redesigned the crossover networks to integrate the new driver array. The networks were developed around phase integration, timing and tonal balance, and are installed in acoustically isolated chambers to reduce exposure to cabinet vibration and microphonic effects.

The company’s Flat Foil Direct Coupling architecture connects crossover components in a star configuration to keep internal paths short. Components are hand-soldered onto a dedicated mounting plate rather than using conventional printed circuit board material in the signal path. Internal wiring is supplied by Kubala-Sosna.

The incoming signal passes through Estelon’s proprietary spring-loaded connector system, which was originally developed for the Extreme Mk II. Copper foil then runs directly to the crossover, reducing the number of metal-to-metal junctions. The terminals accept banana plugs, spade connectors and bare wire, while also supporting bi-wiring.

Sculpted composite enclosure with integrated isolation

The Forza Ultra retains Estelon’s distinctive curved appearance while introducing refinements to the enclosure profile and a new protective grille for the midrange driver. Its patented marble-based composite cabinet uses non-parallel internal surfaces and separate driver chambers to control structural resonance and standing waves.

The curved exterior is intended to reduce diffraction, while the front-baffle geometry aligns the upper drivers and manages high-frequency dispersion across a wider listening area. Each speaker measures 1,675 x 617 x 682 mm and weighs 150 kilograms. Estelon recommends rooms measuring between 40 and 125 square meters.

Stillpoints Ultra SS V2 isolation feet are supplied as standard. Their ceramic bearing system is designed to absorb vibration and limit the transfer of micro-vibrations between the substantial cabinet and the floor.

Amplifier requirements, finishes and availability

The Forza Ultra has a nominal impedance of 3 ohms and reaches a minimum of 2.3 ohms at 51 Hz. Sensitivity is specified at 89 dB for 2.83 volts, while power handling is rated at 400 watts. Estelon recommends amplifier power of at least 20 watts.

New two-tone finishes combine a dark gray base with selected high-gloss colors. Each enclosure undergoes a multi-stage finishing process involving layered painting, wet sanding and hand polishing over several weeks. Custom colors can also be requested.

Deliveries are expected to begin during October. No USD price was provided.

With its purpose-built Accuton driver array, isolated crossover sections, direct-coupled wiring and massive composite enclosure, the Forza Ultra represents an extensive technical update to Estelon’s established sculptural floorstander.