Floorstanding loudspeakers — VAF Research DC-7 MKIII

The DC-7 MkIII is the third generation of VAF Research's slim two-way floorstander, from the Australian loudspeaker maker founded in Adelaide in 1978 by Philip Vafiadis. VAF builds every speaker by hand to order in its own Adelaide factory, and the DC-7 has been part of its range for decades, from the DC-7 Generation 4 kit of the mid-2000s to the current version, designed under lead designer and general manager Simon Wilde.

Key specs that matter

The DC-7 MkIII is a two-way design pairing a 170mm natural-fibre-cone bass/mid driver with a ring-radiator tweeter fitted with a central phase plug. Frequency response is 40Hz to 25kHz, sensitivity is 87dB and impedance is 4 ohms, with amplifiers up to 120W recommended. Each speaker is 19cm wide, 98cm tall and 26.5cm deep, with a weight of 25.5kg. VAF gives a 10-year guarantee, and speakers are built to order with a lead time of about 12 weeks.

Engineering and use context

VAF's design philosophy centres on reproducing the original waveform as closely as possible, treating stored energy as the main enemy of accuracy, and the company regards the first-order crossover as the most phase-linear type because of its simplicity, making driver timing and electrical phase central to its designs. The bass/mid driver has a vented alloy chassis and a vented voice-coil former, so air circulates past the coil and removes heat, reducing thermal compression at high levels. Its proprietary natural-fibre cone sits on a linear suspension and a soft, low-damping rubber surround, the former is made from non-conducting fibre to avoid eddy currents, and an extended copper sleeve on the pole piece lowers voice-coil inductance and distortion. The ring-radiator tweeter uses an annular diaphragm with a phase plug at its centre, controlling dispersion both on and off axis. The slim MDF cabinet keeps its front narrow for a small visual footprint while offering enough internal volume for useful bass extension. VAF suggests the speaker suits small to medium rooms, and it can be used for front or surround channels in home cinema systems.

Pairing

A 4-ohm-capable design is needed here, such as a moderate to powerful solid-state integrated amplifier. Positioning at least a short distance from the rear wall helps bass balance, and a subwoofer from VAF's range extends the bottom octave for home cinema.

Alternatives

VAF Research's own Signature i66 MkIII is a larger three-way floorstander with magnesium-alloy drivers and bass extension to 25Hz.