Напольная акустика — Unison Research MAX 2

Unison Research built the MAX 2 as a two-way floorstanding design - the Italian company is best known for valve amplifiers and hybrid electronics. It was conceived to be driven in particular by the brand's own valve amplifiers, and for that purpose Unison Research optimised both its sensitivity and its impedance rather than sensitivity alone. Production has ended.

Key specs that matter

One 15 inch woofer handles everything below 800 Hz, where the network hands over to a 1.4 inch compression driver whose diaphragm is made of titanium. The woofer is rolled off with a 12 dB slope and the compression driver is brought in with a 6 dB slope. Unison Research quotes a frequency response of 30 Hz to 20,000 Hz and a sensitivity of 96 dB measured with 2.83 Vrms at 1 metre. Nominal impedance is 8 ohm, and the minimum does not fall below 7.4 ohm. Each cabinet stands 101 cm high, 43.5 cm wide and 54 cm deep, and weighs 60 kg.

Engineering and use context

The enclosure is reflex loaded, and its ducts fire forward through the front baffle. The maker chose this layout to make the cabinets easier to position, and describes the box as large in size yet compact for its woofer size. The low crossover point leaves the compression driver to handle most of the midrange and all of the treble. The high minimum impedance means the load stays close to its nominal value across the band, which is the kind of load the design brief set out to give valve amplifiers. The maker also describes the MAX 2 as suitable as a front pair in a home theatre, and states that two pairs, placed front and rear, form a multichannel system that works without a centre channel or subwoofer.

Pairing

Unison Research lists a suitable amplifier range of 10 W to 200 W RMS or more, so the speaker can be run from a low-powered single-ended valve design at one end or a large transistor amplifier at the other, and a power handling rating of 500 W RMS keeps even the bigger amplifiers inside the speaker's limits. Taken together, the flat load and high efficiency make the brand's valve integrated amplifiers the intended partners.

Alternatives

The Unison Research MAX 1 is the more compact floorstander from that range, pairing a 12 inch woofer with a 1 inch titanium compression driver for 94 dB sensitivity in a 95 cm tall, 37 kg cabinet.