Напольная акустика — Blumenhofer Acoustics Corona 2x220

Blumenhofer Acoustics, the German maker where Thomas Blumenhofer has developed speakers for more than 30 years, designed the Corona 2x220 as a two-way floorstander built around horns. It sat in the Corona family next to the Corona 4x180 until Blumenhofer tidied its catalogue and renamed it Gioia 2x220. The maker stresses that nothing apart from the name changed. The concept puts two proprietary 20 cm woofers into a horn-loaded construction, which Blumenhofer says raises their speed and efficiency, and tops them with a mid-high horn that draws on what the firm had learned in the preceding years. Blumenhofer calls it a compact front horn.

Key specs that matter

A pair of 220 mm (8 inch) woofers with paper P2F sandwich membranes covers the low range. At 850 Hz the signal passes to a 1.4 inch compression driver whose 75 mm (3 inch) diaphragm is made of titanium and which fires through its own horn. Blumenhofer specifies a frequency range of 36 Hz to 20 kHz within plus or minus 2 dB. The cabinet measures 450 x 630 x 1130 mm, and each speaker weighs 60 kg.

Engineering and use context

Birch plywood about 19 mm thick forms the cabinet, while the horn itself is formed from HDF complex. Inside, the low section works as a front-ported reflex box, described by the maker as resonance and flow optimised, and Blumenhofer lists its waveformer technology for this model. The cabinet follows what the company calls harmonic construction. Its walls are not parallel, which is meant to prevent standing waves in the bass box, and each panel is tuned to a chosen resonance so that surplus energy is spread across a wider frequency band instead of being damped out completely. The drivers are time aligned. According to Blumenhofer, its P2F membranes came out of joint work with ATE in Ulm, and Ehman and Partner in Gundelsheim built them into the finished bass drivers. Adjustable spikes are fitted, true-wood veneers can be ordered from the workshop, and Blumenhofer grants a five-year warranty.

Pairing

Efficiency is 96 dB, the nominal impedance is 4 ohm and the maximum input is 300 W RMS. The crossover has a switchable impedance linearisation, because Blumenhofer holds that the average valve amplifier needs a flat load, and the company labels the model tube friendly. Its terminal panel, in gold-plated tellurium copper, is prepared for both bi-wiring and bi-amping.

Alternatives

The Blumenhofer Corona 4x180 P is the related two-way tower that replaces the two larger woofers with four 17 cm paper woofers and crosses to the same kind of titanium compression driver at 1000 Hz.