Напольная акустика — Raidho Acoustics D4.1

Raidho Acoustics of Denmark, which produces its own drive units, built the D4.1 as a three-way tower for its Diamond Series. Raidho created it on the basis of its larger D5, aiming to carry over as many of that model's qualities as possible into a more compact cabinet. The D4.1 was introduced at High End 2016 in Munich as part of the revised D X.1 generation, and Raidho now files it among its earlier, archived products.

Key specs that matter

The array counts seven drivers - four bass units, two 4 inch midrange drivers and the Raidho sealed ribbon tweeter, with all cones using Raidho diamond drivers. The upper crossover point is 3 kHz, and the network combines second-order and fourth-order slopes. Raidho rates the frequency range at 25 Hz to 50 kHz and the sensitivity at 89 dB at 2.83 V and 1 m, with nominal impedance above 6 ohm and a call for more than 50 W of amplifier power. Each cabinet is 200 mm wide, 1,550 mm high and 600 mm deep, or 440 x 1,580 x 600 mm on its feet, and weighs 64 kg. Finishes include black piano lacquer, walnut burl veneer and any paint colour to order.

Engineering and use context

Compared with the previous D4, the X.1 revision brought reworked reflex ports and a cabinet streamlined at the back. A rear-mounted port vents the box, and the narrow front leaves room for the vertical stack of seven drivers. Using four bass units rather than one large woofer spreads the low-frequency work across several light diaphragms, and the maker describes the result as full range. The tweeter is a planar magnetic ribbon, hand-built in Denmark, in which conductive tracks are etched into a foil only 11 microns thick. With no voice coil and a moving mass of about 20 milligrams, roughly 50 times less than a conventional dome, its breakup point lies at 82 kHz according to Raidho. The maker aims the D4.1 at listeners who value their music and are willing to spend time on building and fine-tuning a system for the best performance.

Pairing

The impedance and sensitivity ratings keep the load moderate, and Raidho states that besides solid-state designs small tube amplifiers work with the speaker, provided the power minimum is met. At its launch show the pair was demonstrated with an Aavik preamplifier and power amplifier.

Alternatives

The Raidho D3.1 is a smaller tower from the same Diamond Series, likewise archived by the maker among its earlier models.