Усилители мощности моно — Emotiva BasX A1

The BasX A1 is a monoblock power amplifier from Emotiva, the Nashville company, and the only single-channel model in its BasX range, which sits below the XPA series. It appeared around 2022 and is currently listed at USD 569 per unit. A stereo system uses two of them, and in a home cinema a single A1 can add a high-power channel to a multichannel setup.

Key specs that matter

Rated output is 200 W RMS into 8 ohms from 20 Hz to 20 kHz at under 0.05% THD, and 325 W RMS into 4 ohms measured at 1 kHz at under 0.1% THD. Power bandwidth is 20 Hz to 20 kHz within ±0.07 dB, and the small-signal response extends from 5 Hz to 80 kHz at +0/-1.8 dB. Input sensitivity is 1.6 V for full power into 8 ohms, gain is 29 dB and input impedance is 27 kohms. Distortion plus noise at rated power stays under 0.02% A-weighted, A-weighted noise lies more than 112 dB below full output, and the damping factor exceeds 500 into 8 ohms. The minimum recommended load is 4 ohms. The only input is a single RCA socket, with no XLR connection or loop-through output. The chassis measures about 432 x 102 x 394 mm and the amplifier weighs about 10 kg.

Engineering and use context

The output stage works in Class A/B and draws on a heavy-duty linear power supply, and its toroidal transformer is a large one. Damping factor is the ratio of the loudspeaker impedance to the amplifier output impedance, and a figure this high means the amplifier presents a very low source impedance to the woofer and controls its movement after each signal. Protection circuits cover over-temperature, short-circuited speaker outputs and ground faults. The trigger input accepts 5 to 12 V AC or DC at under 10 mA, and the trigger output provides 12 V DC at up to 120 mA, so a preamplifier can wake the A1 and the A1 can pass the command on to another amplifier. The mains input detects 115 V or 230 V at 50 or 60 Hz automatically. Speakers connect through 5-way binding posts, and the steel chassis wears a milled aluminium front panel. A three-year warranty covers the A1.

Pairing

The input sensitivity means any preamplifier or AV processor with a standard 2 V RCA output can drive the A1 to full power. Processors with only balanced outputs need an adapter or a different amplifier, since there is no XLR input. With its large reserve into low impedances, a pair suits demanding floorstanders.

Alternatives

The Emotiva XPA-1 Gen3 is a larger mono amplifier with XLR and RCA inputs, rated at 300 W into 8 ohms and 600 W into 4 ohms.