Полочная акустика — Leak Sandwich 250

The Sandwich 250 is a three-way stand-mounted design from Leak. The company's first Sandwich model appeared in 1961 with a cone of expanded polystyrene foam held between aluminium foil sheets. The current model revives that construction in both its bass and midrange drivers. The 250 tops the two-model Sandwich series, above the two-way Sandwich 150. Launch pricing was GBP 1,999 per pair, or GBP 2,299 with a dedicated floor stand.

Key specs that matter

Leak quotes a response of 42 Hz to 26 kHz within 3 dB and bass extension to 32 Hz at the 6 dB point. Sensitivity is 88.5 dB at 2.83 V and 1 m, and peak output is rated at 112 dB. Impedance is 6 ohm nominal, described as 8 ohm compatible, with a minimum of 4 ohm. Recommended amplifier power is 25 W to 250 W. The crossover divides the signal at 470 Hz and 3.1 kHz. Each speaker is 655 mm high, 370 mm wide and 300 mm deep, plus 30 mm for the terminals, and weighs 27.3 kg.

Engineering and use context

Leak fits an 11 inch (280 mm) bass driver and a 4.25 inch (108 mm) midrange, both carrying Leak's Aluminium-Foamcore Sandwich cone. A 30 mm coated textile dome tweeter covers the top octaves. Leak lists two internal volumes, 2.7 litres and 45.5 litres for the enclosure, the small one assigned to the midrange section and the large one to the bass reflex system. The cabinet is dual-ported, and its walls combine an outer layer of MDF with an inner skin of high-density particle board, with a glue filling between the two to scatter and damp resonances, and internal spot bracing plus one front-to-rear brace stiffen the panels further. With an 11 inch cone in a 45.5 litre volume, the 250 moves far more air than its two-way sibling, hence its deeper reach in the bass. The finish is real walnut veneer applied by hand, set off by aluminium trims around the drivers. The midrange covers everything between the two crossover points, so the large bass cone never has to reproduce voice frequencies. Leak supplies rubber feet with each speaker, while its purpose-built floor stand is an extra purchase.

Pairing

The low impedance minimum and the wide power window make a transistor integrated with spare current capacity a sensible match, and Leak's own Stereo 130 or Stereo 230 amplifiers share the same retro styling. At this size and weight the speaker needs a sturdy, low stand, and Leak's dedicated stand is designed for the cabinet footprint. The ported enclosure also wants some distance from the rear wall in a room of around 20 m2.

Alternatives

The Leak Sandwich 150 is the smaller two-way standmount in the series, built around a single 170 mm Sandwich mid-bass driver.