Malac — Accuton/Davis mini-monitor
Small loudspeakers are sometimes the only acceptable choice for a home system. Size may be dictated by available space, appearance or simply budget. This project is unlikely to interest anyone choosing small speakers primarily to save money. Malac requires about €600 for drivers and another €100 for crossovers, connectors and miscellaneous parts. Including cabinet construction, materials may total €1,000. Good stands usually need to be added to that.
Although fairly expensive to build, Malac is a high-quality speaker whose small dimensions do not significantly restrict its sonic abilities. Deafening volume, high sensitivity and devastating bass are impossible expectations, of course. Musicality, resolution and tonal balance, however, can compare with much more expensive commercial products of any size.
Malac is a two-way system with a bass-reflex bass/midrange section. The German Accuton tweeter is distinguished by its inverted, 30 mm ceramic diaphragm. Together with a small voice coil and strong magnet, this exceptionally rigid diaphragm allows linear operation from 1.5 kHz to beyond 20 kHz. Resonance is an impressively low 350 Hz, allowing a first-order crossover at a relatively low frequency. The C23’s excellent performance has made it a frequent choice in top-class and often equally expensive loudspeakers.
The bass/midrange is the Davis Acoustics Velvet 13 from France. This OEM variant of the 13 KLV 5MA adds graphite sandblasting to the normally yellow woven-Kevlar cone. The treatment breaks up the weave’s surface structure while depositing graphite, which the designer says further refines the original driver’s sound. The original and Velvet versions have sufficiently similar characteristics to be used in the same project without cabinet or crossover changes.
Velvet 13 offers a very flat frequency response and respectable bass performance for its size. Its Thiele/Small parameters favour bass-reflex loading. Malac therefore uses a rigid combination of 18 mm MDF and a thick plywood front panel, with a volume of approximately nine litres. An internal ring brace also supports the bass/midrange magnet through a rubber pad. A 4 mm bitumen layer damps the cabinet walls, while profiled acoustic foam and polyester wadding damp the interior. The port has a 45 mm internal diameter, a length of 110 mm and rounded ends to reduce turbulence and the resulting chuffing at high levels. Tuning is 52 Hz.
The crossover is first-order. The bass/midrange also has two series RLC equalisation networks and a parallel RC network to compensate its inductance. The high-pass section uses a single capacitor and two resistors as an attenuating voltage divider. Components are very good quality: polypropylene capacitors, metal-oxide resistors, a foil main inductor and ferrite-core inductors in the RLC networks. The 4 kHz crossover and broad overlap between driver operating ranges produce an inaudible transition.
The result is very linear.
At tweeter height, 30° horizontally off-axis:
The speakers are intended for stands that put the tweeter at ear level or a few centimetres above. They should be at least around thirty centimetres from the rear wall.
DrZ Lab