LEAK - Sandwich 150 Bookshelf Speakers (Pair)

The heart of LEAK’s revived Sandwich range: a 170mm aluminium-foamcore cone in a braced walnut cabinet, reviving a driver principle LEAK introduced in 1961.

The Sandwich 150 launched in 2024 alongside the larger Sandwich 250 as the first speakers to carry the Sandwich name since the original range ended in the 1970s. It is a 19.6-litre two-way standmount pairing a 170mm Sandwich-cone mid/bass driver with a 30mm coated textile dome, crossed over at 2.4kHz.

The original is worth getting right, because it matters. In 1961 Don Barlow, working for H. J. Leak & Co., built a cone from expanded polystyrene foam sandwiched between two sheets of aluminium foil. The result was simultaneously very light and many times stiffer than the paper, plastic or plain aluminium cones of the day, and Harold Leak publicised its rigidity with a photograph of himself standing on top of one. The modern cone follows the same principle with different materials: a polymethacrylimide structural foam core between aluminium skins, bonded with aerospace-grade adhesives. Related in idea, not identical in substance.

The tweeter has a detail worth knowing. Its rear chamber is damped so that the dome’s own resonant frequency falls below the crossover point, which meant LEAK could use a gentler crossover slope rather than a steeper one working to suppress a resonance sitting in the passband.

The cabinet is a layered composition of MDF and composite board — a second, deliberate sandwich reference — with bracing that includes a specific front-to-rear brace whose countersunk fixing screw is visible on the rear panel. That is not a blemish; it is a revival of a signature detail of the 1960s LEAK cabinets. It is finished in real walnut veneer with an aluminium trim insert to match the Stereo 130 and 230, and supplied as a handed, mirror-imaged matched pair.

Features

• Two-way vented-box standmount, 19.6 litres, supplied as a handed mirror-imaged pair
• 6.5″ (170mm) aluminium-foamcore Sandwich cone bass driver — polymethacrylimide foam core between aluminium skins
• 1.2″ (30mm) coated textile dome tweeter with damped rear chamber
• Crossover at 2.4kHz, made gentler by the tweeter’s lowered resonance
• Layered MDF and composite cabinet with front-to-rear bracing
• Visible countersunk rear brace screw, a revival of the original 1960s detail
• Rear-ported — allow clearance behind the cabinet
• Real wood walnut veneer with aluminium trim insert
• Removable acoustically transparent cloth grille supplied
• Driver principle descended from the 1961 LEAK Sandwich designed by Don Barlow
• Natural partner for the LEAK Stereo 130 and Stereo 230

Specifications

• Type: Two-way vented-box standmount loudspeaker, bass reflex
• Bass Driver: 6.5″ (170mm) aluminium-foamcore Sandwich cone
• Cone Construction: Polymethacrylimide structural foam core between aluminium skins
• Treble Driver: 1.2″ (30mm) coated textile dome with damped rear chamber
• Sensitivity: 86.5dB (2.83V at 1m)
• Recommended Amplifier Power: 25–150W
• Peak SPL: 106dB
• Nominal Impedance: 6Ω (8Ω compatible)
• Minimum Impedance: 4Ω
• Frequency Response: 44Hz–26kHz (±3dB)
• Bass Extension: 38Hz (−6dB)
• Crossover Frequency: 2.4kHz
• Cabinet Volume: 19.6 L
• Cabinet Construction: Layered MDF and composite board with bracing, including a visible front-to-rear brace
• Porting: Rear-firing bass reflex
• Pair Configuration: Handed, mirror-imaged matched pair
• Height on Plinth: 415 mm (16.3″)
• Width: 250 mm (9.8″)
• Depth with Terminals: 290 + 25 mm (11.4″ + 1.0″)
• Net Weight: 12.3 kg (27.1 lbs) each
• Gross Weight: 27 kg (59.5 lbs) per carton
• Carton Size: 650 x 400 x 530 mm
• Finish: Real wood veneer, walnut, with aluminium trim insert
• Supplied Accessories: Rubber feet, removable cloth grilles, user manual
• Sold: As a pair
• Note: LEAK does not publish the speaker terminal configuration, the port count or the grille attachment method for this model. The 26kHz upper figure is LEAK’s own; the smaller Sandwich 100 is rated to 20kHz using the same 30mm dome