Напольная акустика — Russell K Red 150Se

The Red 150Se is the special edition of the Russell K Red 150 floorstander, designed by Russell Kauffman, formerly the technical director of the driver maker Morel. It keeps the narrow column and driver layout of the standard model but adds a new tweeter with a metal faceplate, a metal plinth with spikes in place of the MDF one and revised internal tuning with three chambers.

Key specs that matter

The quoted range runs from 20 Hz to 22 kHz depending on the room, and the maker states 87 dB sensitivity at 1 W and 1 m. Height is 950 mm for the cabinet alone and 1,000 mm with plinth, base and spikes, with a width of 240 mm and a depth of 250 mm. Two 6.5 inch bass units with impregnated paper cones sit on high-power ferrite magnets and drive 25 mm voice coils on aluminium formers. The 25 mm soft dome tweeter has a double ferrite magnet system and copper-clad aluminium voice coil wire on a fibreglass former. A sub-bass section is filtered at 80 Hz at 6 dB per octave, and the bass-mid driver crosses to the tweeter at a nominal 2,200 Hz at 12 dB per octave.

Engineering and use context

The enclosure uses 16 mm MDF throughout except for a 19 mm front baffle, and it is left without any damping. Three acoustic loading shelves with multiple apertures sit below the tweeter, below the bass-mid unit and below the sub-bass unit, and one more brace near the bottom holds an internal port. This port vents into a small chamber containing two reflex ports of different lengths, tuned together as one system to 21 Hz. Every driver is wired in positive phase, the phase relationship between them is optimised, and each has only one crossover part. In this two-and-a-half-way arrangement the lower woofer handles only the deepest bass. Real wood veneers and deep piano gloss finishes are offered. Speaker terminals are mounted high on the rear panel and oriented horizontally.

Pairing

The moderate sensitivity allows a conventional solid-state or valve amplifier of moderate power to drive the pair in a 20 m2 room, while the two paper-cone bass units benefit from an amplifier with good current reserve. The metal plinth and spikes are designed to couple the cabinet to a solid floor, and cables with horizontal spade or banana plugs fit the high rear terminals best.

Alternatives

The standard Russell K Red 150 uses the same cabinet and bass units but keeps the earlier tweeter and an MDF plinth.