Floorstanding loudspeakers — Acora Acoustics QRC-2

The QRC-2 takes the driver set and 2.5-way layout of the granite SRC-2 and moves them into a cabinet of polished quartz, making it the larger of the two quartz floorstanders from Acora Acoustics in Scarborough, Ontario. It is priced at USD 37,000 or CAD 49,950 per pair. Its designer Valerio Cora first worked with audio at 13 in a Toronto electronics shop during the 1970s and built speakers for his own use for years before launching the brand.

Key specs that matter

Three drivers form a 2.5-way bass reflex system - two 7 inch sandwich paper cone mid-woofers and a 1 inch beryllium dome tweeter. Rated impedance is 4 ohm and efficiency is 92.5 dB at 1 W and 1 m, 2 dB above the single-woofer QRC-1. Acora gives a frequency range of 29 Hz to 30 kHz and a suggested amplifier range of 10 W to 250 W. The tower stands 109.2 cm high on a 45.7 by 35.6 cm footprint, and the maker quotes about 73 kg per speaker depending on the slab. Standard colours are Nardo and Thasos quartz, cut as 3 cm high-polish sheets.

Engineering and use context

The enclosure is assembled from seven stone pieces bonded with a special epoxy, which leaves no visible seams, and closed at the bottom by a metal plate. Its shape is a tapered pyramid with flared sides intended to limit diffraction. No two inner walls run parallel, so Acora fits no internal bracing and no damping material. The drivers sit flush with the baffle, and their mounting screws are hidden under small black felt dots. Acora modifies the woofers in-house before they go into the cabinet. Threaded spikes under the base adjust in quarter-turn steps, and a set of floor protectors is included in the box. The crossover is designed around phase alignment between the three drivers, and the beryllium dome runs without series resistors.

Pairing

The low nominal rating points to amplifiers that stay stable into low loads and deliver current freely, although the higher efficiency means fewer watts are needed for a given level than with the QRC-1. Owners who prefer aftermarket isolation devices can fit them in place of the supplied spikes. Acora does not tie the QRC-2 to any specific amplifier brand, and the single-cable connection keeps wiring simple for stereo amplifiers and monoblocks alike.

Alternatives

The Acora MRC-2 applies the same 2.5-way layout with two woofers to a marble cabinet weighing about 82 kg and priced at USD 12,990 per pair.