Напольная акустика — Franco Serblin Ktêma

The Ktêma is a four-way tower made by the Italian company Franco Serblin, sold alongside the Accordo, Accordo Essence, Accordo Goldberg, Accordo Unica and Lignea. Its topology uses five drive units in each cabinet, housed in a rigid structure shaped as a triple arch with concave lateral front cheeks.

Key specs that matter

In-room frequency response is quoted as 26 Hz to 33 kHz. Sensitivity is 92 dB at 1 W and 1 m. Nominal impedance is 4 ohm, with a minimum of 3.2 ohm at 70 Hz, and the maker asks for at least 20 W per channel from the amplifier. Each cabinet measures 42.5 cm wide, 46 cm deep and 111 cm tall. The unpacked weight is 110 kg per pair, while the shipping cartons measure 52 x 57 x 110.5 cm and bring the packed total to 127 kg for the pair.

Engineering and use context

High frequencies go to a 28 mm soft dome tweeter designed by Ragnar Lian. Below it sit two custom 100 mm midrange units mounted on a step-compensated baffle and arranged as a cardioid acoustic-resistance design, which shapes how the midrange radiates toward the rear. Low frequencies come from two custom 230 mm metal cone woofers that are compression loaded and fire out of the back of the tower, with a convex woofer compressor forming part of the enclosure. The crossover follows what the company calls a mutational variable slope approach aimed at coherent spatial radiation, rather than a fixed slope for every band. Internal wiring is pure silver-palladium in a mono-wiring layout, which means each cabinet takes one speaker cable run. With a cardioid midrange section and woofers mounted on the rear, each tower radiates energy in more than one direction. Three finishes are offered - high gloss piano black, satin sycamore and high gloss walnut - each combined with hand-polished aluminium parts.

Pairing

Because the woofers fire rearward and the load drops sharply in the upper bass, any amplifier chosen for it needs to remain comfortable with that low load. High efficiency and a modest power minimum mean that low-power valve and solid-state designs both fall within the stated range, as long as they cope with that dip. The single pair of terminals per speaker suits one stereo amplifier rather than a bi-amped arrangement, and a room of about 20 m2 or larger gives the tall towers space around them.

Alternatives

Franco Serblin also makes the Lignea, a much smaller 2-way vented model with a solid wood cabinet that the maker lists as floorstanding.