Piega Coax 811 Gen2 white (pack of 2)

Swiss manufacturer Piega, based in Horgen on the shores of Lake Zurich since 1986, has developed for its Coax Gen2 series a floorstanding speaker that adopts the brand’s characteristic coaxial ribbon architecture, but in unprecedented proportions. Standing 124 cm tall and weighing 63 kg, the COAX 811 fully embraces its status as the flagship of a completely redesigned range, unveiled at the High End show in Munich in 2022.

A coaxial ribbon driver that behaves like a point source

The heart of the COAX 811 lies in its C212+ module, a coaxial driver where the ribbon tweeter is positioned at the exact center of a square-shaped ribbon midrange. This concentric arrangement means both elements radiate from the same point in space. In practice, whatever the listening position, height, or distance, the mid and high frequencies always arrive in phase at the ear. Voices—whether vocal, instrumental, or organ—retain a stable, coherent location within the soundstage.

The diaphragms used are 0.02 mm thick—just a few hairs—and weigh only a fraction of a gram. This lightness provides very high responsiveness to transients. On the 811, the surface area of the coaxial ribbon is larger than on the 411 and 611 models from the same series. The required excursion is therefore reduced, which increases the driver’s dynamic capabilities. The C212+ handles frequencies from 450 Hz upward, covering the critical vocal reproduction range.

Four 220 mm woofers, including two passive radiators

The low-frequency section uses four 220 mm drivers manufactured by Norwegian firm SEAS to Piega’s specifications. Two of them are active and powered by the amplifier. The other two operate as passive radiators, set in motion by the internal acoustic pressure of the cabinet. This system makes it possible to reach a 22 Hz low-frequency response while limiting the excursion of the active woofers. The result: less distortion at high levels and better power handling.

The speaker is a sealed design, with no port. The absence of a port eliminates turbulence noise and the temporal smearing associated with bass‑reflex enclosures. The usual downside of this type of loading—a lower efficiency in the very deep bass—is offset here by the generous cabinet volume and the contribution of the passive radiators.

An aluminum cabinet under controlled tension

The seamless extruded aluminum shell has long been a Piega hallmark. Aluminum offers rigidity and low mass but has a drawback: it can resonate like a bell. To counter this tendency, Piega has developed the TIM2 system (Tension Improve Module, second generation).

Ten vertical rails integrated into the extruded profile are pulled toward the center of the column by four horizontally mounted, machined solid‑aluminum plates, tightened by hand during assembly. The cabinet is therefore kept under constant tension. The difference compared with the first‑generation TIM: the old system exerted pressure outward, whereas TIM2 pulls inward. This approach improves structural rigidity. Viscoelastic sheets placed inside absorb any residual resonances.

Swiss architect Stephan Hürlemann designed the silhouette of the column: a slightly curved front baffle and an oval profile tapering toward the rear. The design dates back several years but hasn’t aged a day.

Placement and amplification

With a nominal impedance of 4 ohms and a rated sensitivity of 92 dB, the COAX 811 is quite easygoing in terms of amplification. Piega specifies a range of 20 to 250 W. A modest amplifier can therefore drive it, although a healthy power reserve makes it possible to fully exploit its dynamic capabilities at high listening levels.

The speaker is equipped with two pairs of binding posts for bi‑wiring or bi‑amping. Jumpers are supplied for single‑wire use.

The weight of 63 kg per speaker makes handling tricky but manageable for two people. Once installed, the mass contributes to stability. The grilles are magnetically attached and sit flush with the cabinet. Piega supplies a magnetic tool shaped like an oversized chess pawn to remove them without damaging the fabric.

Technical specifications

Transducers and acoustic system

• Coaxial ribbon C212+
  • Clear, precise highs and mids
  • Larger diaphragm surface than on Coax 411 and 611 models
  • Reduced excursion for greater dynamics and openness
  • Frequencies always emitted in phase for precise sound imaging
• UHQD woofers and bass reproduction
  • 2 active 220 mm woofers
  • 2 passive 220 mm radiators
  • Manufactured by SEAS to Piega specifications
  • Powerful, precise, and dynamic bass

Cabinet and construction

• Extruded aluminum cabinet
  • Seamless construction for optimal rigidity
  • Effective reduction of unwanted resonances
• TIM2 module (Tension Improvement Module 2)
  • Cabinet tension control system
  • Reduces speaker resonances for purer sound

Electroacoustic specifications

• Type: 3-way floorstanding speaker
• Recommended amplifier power: 20 – 250 W
• Sensitivity: 92 dB/W/m
• Nominal impedance: 4 Ω
• Frequency response: 22 Hz – 50 kHz

Dimensions and weight

• Dimensions (H × W × D): 124 × 29 × 42 cm
• Weight: 63 kg

Available finishes

• Standard finishes: brushed silver aluminum, brushed black anodized aluminum, white lacquered