Напольная акустика — Closer Acoustics Adam

Adam is a floorstanding loudspeaker from Closer Acoustics, the Polish company run by brothers Jacek and Andrzej Grodecki. Jacek is responsible for the concept and voicing, while Andrzej, whose main trade is furniture restoration, builds the cabinets. The firm makes its own mechanical parts, including feet and knobs, as well as the flight cases in which the speakers are shipped. The unusual cabinet outline of Adam is the same shape that appears in the company logo.

Key specs that matter

Adam is a two-way design with two drivers. The main unit is a 200 mm Supravox 215 Signature full-range driver in its single-cone version, run without a crossover. Its light uncoated cellulose cone has a moving mass of only 9 g, a 25 mm dust cap and a three-fold top suspension formed from the cone itself, and on axis it reaches about 10 kHz. Above that point a B&C Speakers DE35 compression driver on a horn takes over, with a 32 mm diaphragm, a neodymium magnet and a working band of 3,500 to 18,000 Hz. Closer Acoustics rates the speaker at 94 dB efficiency, 8 ohm and 35 W. Each cabinet is 1170 mm tall, 305 mm wide and 440 mm deep and weighs 43 kg.

Engineering and use context

Supravox recommends a tapered quarter wave tube for this driver and rules out a conventional bass reflex box. The Adam enclosure combines two transmission lines of different lengths and uses no damping material at all - acoustic energy is dissipated directly in the system of internal channels. The lines exit through two narrow slots, one on the rear panel and one on the underside. The cabinet is glued from birch plywood that is milled out on the inside, and the side walls are reinforced with panels of Corian, the DuPont mineral composite used for worktops. The speaker stands on brass spikes, and the signal enters through a single pair of CMC terminals made of pure copper with gold plating, so bi-wiring is not possible.

Pairing

The high efficiency figure was chosen with low-power valve amplification in mind. Closer Acoustics demonstrates Adam with its own 300B Provocateur, a single-ended class A integrated amplifier rated at 8 W, and similar 300B designs are a logical match. The modest power rating rules out driving the speaker hard with powerful solid-state amplifiers.

Alternatives

The Closer Acoustics Allegra is another floorstander from the brand, built around an 8-inch EMS LB8 full-range driver and rated at 93 dB, 40 W and 40 Hz to 19 kHz in a 117 cm tall cabinet.