Усилители мощности стерео — Electrocompaniet AW250 R

The AW250 R is a stereo power amplifier from Electrocompaniet, the Norwegian electronics company that designs and manufactures its products in Norway. It uses a dual mono class A/B layout with balanced circuitry. In Europe it has been sold at around EUR 9,600.

Key specs that matter

Rated output is 2 x 250 W into 8 ohm, 2 x 380 W into 4 ohm, 2 x 625 W into 2 ohm and 2 x 1,100 W into 1 ohm. Electrocompaniet quotes an output impedance below 0.008 ohm across 20 Hz to 20 kHz and a peak current capability above 100 A. Distortion stays under 0.001% at 1 kHz both at half power and at 1 dB below full output. Noise with the inputs shorted measures 90 microvolts between 400 Hz and 30 kHz and 100 microvolts between 10 Hz and 30 kHz. The XLR input has an impedance of 110 kohm, and 1 V drives the amplifier to rated power. Frequency response is listed from 0.1 Hz to 100 kHz. With no load connected the unit draws 230 W from the mains. The chassis is 483 mm wide, 450 mm deep and 210 mm high, and it weighs 39 kg.

Engineering and use context

Each channel is built as its own monophonic balanced circuit. The power supply follows Electrocompaniet's Floating Transformer Technology, abbreviated FTT, which the company says can deliver twice the current of a conventional supply. Two 650 VA toroidal transformers feed a total filter capacitance of 120,000 microfarads. The low output impedance corresponds to a damping factor quoted at more than 1,000. The AW250 R accepts only balanced XLR connections and has no RCA inputs. Two sets of speaker terminals are fitted per channel, and a balanced link output passes the signal on to further amplifiers for bi-amping. In bridged mode the AW250 R becomes a mono amplifier with up to four times the power of one channel. The top panel is vented, and the chassis rests on isolation feet that leave an air gap beneath it.

Pairing

The XLR-only input needs a preamp or DAC fitted with XLR outputs, such as Electrocompaniet's own EC 4.8 MKII or EC5 preamplifiers. Its current reserve and the 1 ohm rating make it suitable for loudspeakers whose impedance dips well below 4 ohm, and owners of large bi-wirable models can add a second unit through the link output and drive the bass and upper sections separately.

Alternatives

The AW250 R is the only stereo power amplifier in the current Electrocompaniet range, where the other power amplifiers are monoblocks.