Полочная акустика — Castle Richmond IV

The Richmond IV is a two-way standmount loudspeaker from the British maker Castle and the fourth generation of the Richmond, a compact model Castle itself calls a classic miniature. It follows the Richmond 3i, and Castle states that the new version draws on more than 35 years of in-house loudspeaker design. The price is EUR 700 per pair, and the model is offered as a bookshelf or standmount design.

Key specs that matter

A 150 mm bass unit works with a 32 mm soft dome tweeter, and the crossover hands over between them at 2.6 kHz. Castle quotes a frequency range of 58 Hz to 22 kHz at the -3 dB points and a sensitivity of 87 dB. Nominal impedance is 8 ohm with a minimum of 4.3 ohm. The recommended amplifier power is 25 to 100 W. Each cabinet measures 305 mm high, 190 mm wide and 262 mm deep and weighs 6.3 kg, and a pair ships in one carton of 14.5 kg with rubber feet included. Two finishes are listed - Black Oak and Mahogany.

Engineering and use context

The bass driver uses a newly developed motor system that Castle designed for linear excursion, and it is larger than the unit in earlier Richmond versions. Because of the high crossover point, this cone covers the whole midrange as well as the bass, which is why Castle aimed the new motor at midrange precision as much as low-frequency output. The tweeter dome is backed by a rear chamber, which takes up the rearward output of the dome so it does not bounce back onto the diaphragm. Bass loading is reflex, vented through a port that exits at the back. Where the Richmond 3i used a 15 mm MDF cabinet with bitumen damping pads, the Richmond IV moves to multi-layer composite panels, chosen after vibration analysis of the whole box. A loose fibre weave inside the cabinet absorbs internal reflections, and targeted bracing stiffens the panels so that the drive units are not undermined by cabinet movement.

Pairing

The recommended power window and the low impedance minimum suggest a solid-state integrated or stereo amplifier that is stable into 4 ohm, while the modest sensitivity favours outputs toward the upper part of that range in larger spaces. A low-powered valve amplifier of only a few watts sits below the lower limit Castle quotes.

Alternatives

The Castle Tintagel 1 is a compact standmount from the Tintagel series, which Castle hand-builds and hand-finishes in the UK.