Abacus

Abacus takes the oldest calculating tool there is and turns it into light. Strands of hand-blown opal glass spheres, each 7cm across, hang from fine brass rods at staggered heights, so the whole piece reads like a column of figures caught mid-sum. Switched off, it is a calm, graphic object in white and brass. Switched on, every sphere glows evenly from within, a soft, uniform light with no visible source, and the largest linear form carries 115 of them.

It was designed for Terzani by Draw, the studio of Luca Martorano and Mattia Albicini. Their starting point was the abacus itself: a few simple parts that handle a small sum or a complex formula equally well. Abacus scales in the same way. A single strand of five spheres is a pendant for a bedside or a reading corner; strands of five, ten and fifteen spheres combine into round clusters of three or seven, or into linear runs up to 175cm long.

Each sphere is hand-blown in opal glass to Terzani's own specification, and each strand carries an integrated, replaceable LED module at a warm 3000K.

In the room

Over a dining table, choose a linear form. As a guide, the 70cm suits a kitchen island or a table for four, the 140cm a table for six to eight, and the 175cm a long table for ten or more. The strands rise and fall in a soft skyline rather than a solid mass, so the piece has presence without blocking the room, and at 12,420 lumens the largest form lights a long table on its own.

In a stairwell, a double-height hall or a hotel lobby, the seven-strand clusters come into their own: the tallest drops 145cm of glowing glass through the space, and longer suspension can be made to order. The three-strand clusters and single strands are made to be grouped, in a line over an island, in pairs beside a bed, or at staggered heights over a reception desk. The wall sconce, a single five-sphere strand on a brass arm, carries the same idea along a corridor or either side of a mirror.

Because the light comes through opal glass rather than from a bare lamp, Abacus can run bright for a working kitchen or meeting room and dim right down to a low glow for dinner. Terzani designed it to sit as comfortably in a commercial interior as in a private house.

Hand-crafted by Terzani's artisans in Florence.

Configurations

• Single strand, 5 spheres, 35cm tall, 3.6W LED, 540 lm, 1.6kg (0.4kg on a ceiling disc)
• Single strand, 10 spheres, 70cm tall, 7.2W LED, 1,080 lm, 1.7kg (0.6kg on a ceiling disc)
• Single strand, 15 spheres, 105cm tall, 10.8W LED, 1,620 lm, 2kg (0.9kg on a ceiling disc)
• Cluster of 3, 3 x 5 spheres, Ø20cm, 50cm tall, 1,620 lm, 2.5kg
• Cluster of 3, 3 x 10 spheres, Ø20cm, 100cm tall, 3,240 lm, 3kg
• Cluster of 3, 3 x 15 spheres, Ø20cm, 130cm tall, 4,860 lm, 3.2kg
• Cluster of 7, 7 x 5 spheres, Ø30cm, 55cm tall, 3,780 lm, 4kg
• Cluster of 7, 7 x 10 spheres, Ø30cm, 110cm tall, 7,560 lm, 6kg
• Cluster of 7, 7 x 15 spheres, Ø30cm, 145cm tall, 11,340 lm, 9.6kg
• Linear, 3 x 5 and 3 x 10 spheres, 70cm long, 100cm tall, 4,860 lm, 7kg
• Linear, 6 x 5 and 6 x 10 spheres, 140cm long, 100cm tall, 9,720 lm, 13kg
• Linear, 7 x 5 and 8 x 10 spheres, 175cm long, 100cm tall, 12,420 lm, 32kg
• Wall sconce, 5 spheres on a brass arm, 54cm tall, 14cm projection, 540 lm, 1.6kg

Specification

• Designer: Draw (Luca Martorano and Mattia Albicini)
• Materials: Hand-blown opal glass spheres, Ø7cm, brass
• Canopy: Painted brass or white; white ceiling disc option on single strands; brass backplate on the wall sconce
• Cord: Champagne fabric
• Light source: Integrated replaceable LED module, 3.6W and 540 lm per five spheres
• Colour temperature: 3000K
• Dimming: Standard versions 0-10V or PWM; DALI versions also accept push, 1-10V and 100kΩ control; wall sconce push or 1-10V
• Power: 220-240V through the canopy; ceiling disc versions run at 12V from a remote driver, driver included in the price
• Suspension: Up to 190cm overall, adjustable on site; longer drops to order
• Certification: CE
• Origin: Made in Italy

Every Abacus is made to order. Caspen manages the specification with you, from configuration and canopy finish to the control system your electrician will connect, and confirms the lead time when you order. Bespoke cluster layouts, sphere counts, canopy finishes and suspension lengths are available through the studio.