Полочная акустика — Piega COAX 411

The Coax 411 is the stand-mount model of Piega's Coax Gen2 series, and Piega presents it as the entry point into its coaxial ribbon technology. Piega designs and builds its loudspeakers in Switzerland, and the Gen2 update brought new coaxial ribbon drivers, larger extruded aluminium cabinets and improved resonance control. The cabinet shape was designed by Swiss designer Stephan Hürlemann.

Key specs that matter

The Coax 411 is a ported three-way that combines a C112+ coaxial ribbon, which reproduces both midrange and treble, with a 160mm UHQD woofer made by SEAS to Piega's specifications. Frequency response is 35Hz to 50kHz, sensitivity is 90dB/W/m, impedance is 4 ohms and recommended amplification is 20 to 200W. Twin terminal pairs support separate feeds to the woofer and coaxial sections. Each speaker measures 45 x 21 x 31cm and weighs 25kg. Finishes are brushed silver aluminium, black anodised aluminium or white lacquer, with eight further Coax Excellence colours available for the Gen2 range.

Engineering and use context

In the C112+ coaxial ribbon, a ring-shaped ribbon midrange surrounds a central ribbon tweeter, with the two drivers arranged point-symmetrically on one plane. Both radiate from the same point, so the acoustic source stays in one position across a wide frequency range, which gives consistent timing and impulse behaviour without the offset between separate tweeter and midrange drivers. A ribbon diaphragm is an extremely thin, light conductor driven directly by the magnetic field over its whole surface, so it responds quickly with very little stored energy, and the ribbon's wide high-frequency extension follows from that low mass. The cabinet is extruded as a one-piece aluminium section, far stiffer than wood-based panels of similar thickness, and the Gen2 version adds TIM2 (Tension Improve Module 2) - an internal element that holds the cabinet walls under controlled tension to calm resonances - together with viscoelastic damping foils. Each Gen2 cabinet is larger than its predecessor's, giving the woofer more internal volume.

Pairing

Its low nominal impedance suggests an amplifier happy with low loads, while the fairly high sensitivity means moderate power produces useful levels. Heavy, rigid stands suited to the dense aluminium cabinet are needed, and the twin terminals allow bi-amping. Piega aims the Coax 411 at small to medium rooms, where its deep bass extension removes the need for a subwoofer in most cases.

Alternatives

Piega's own Coax 511 is the floorstanding Gen2 model using the larger C212+ coaxial ribbon and two woofers.