Floorstanding loudspeakers — Piega MASTER LINE SOURCE MKII

The Master Line Source MKII is a passive dipole loudspeaker system from Piega of Switzerland, built on the line source principle rather than the point source layout of the brand's coaxial speakers. Each channel is made of two parts - a slim panel for the midrange and treble and a separate bass tower of the same height. Piega sells it on price request and offers custom designs beyond the standard finishes.

Key specs that matter

The system works as a three-way design. Eight Line Source Driver 211 ribbons in the panel handle midrange and treble, and six 220 mm UHQD woofers with aluminium membranes fill the bass tower. Piega quotes 18 Hz to 50 kHz, 94 dB at 1 W and 1 m and 4 ohm nominal impedance, and the amplifier range runs from 20 up to 1000 W. The panel measures 178 x 44 x 5 cm and the bass tower 178 x 38 x 60 cm (height, width, depth), and the listed total weight is 600 kg.

Engineering and use context

Stacking the ribbons vertically into one tall column produces a cylindrical wave front instead of a spherical one, which is the core of the line source concept. Because the panel is a dipole, the ribbons radiate the midrange and treble both forwards and backwards. The bass cabinets use MDF composite with elaborate internal bracing and sound-absorbing material, sandwiched with solid aluminium panels 10 mm thick for stiffness. The baffle of the midrange panel is machined from a single solid block of a special aluminium alloy, which goes through an hour-long annealing process to relieve internal stress before machining. Connection is by bi-wiring through WBT terminals. The standard finishes are polished aluminium paired with a silver cover, or a black anodised body with a black cover.

Pairing

The high sensitivity means that even the lower end of the power range will drive the system, while the high ceiling means very powerful transistor amps can also be used. The low nominal impedance still favours amplifiers with a strong current supply. Thanks to the WBT pairs, owners can run separate cables to the panel and the bass section, or bi-amp the system with one amp for the ribbons and another for the woofers. The dipole panel needs free space behind it, and the considerable total weight should be planned for when choosing the floor and moving the parts into position.

Alternatives

The Piega Master Line Source 3 is a smaller single-cabinet line source dipole with four ribbons, two 180 mm bass drivers and two passive radiators, standing 165 cm tall and weighing 65 kg.