Усилители мощности стерео — Extraudio XP-A1500 MKII

The XP-A1500 MKII is a dual-mono, fully balanced stereo power amplifier from Extraudio, a Dutch company that has developed its amplification technology since 2008. It was produced from 2018 to 2020 and is now discontinued, and owners can have it updated to the 2022 model. Extraudio also made the XP-A800 power amplifier as a smaller model from the same period, and the X800 MKII integrated amplifier combines the XP5 preamplifier with the XP-A800 in one box.

Key specs that matter

Output is 1500 W per channel into 8 ohm and 2400 W into 4 ohm. Two power supplies rated at 1500 W peak each deliver up to 90 A peak per channel. The damping factor exceeds 1000 into 8 ohm at 1 kHz and below, and gain is 28 dB. Frequency response is 2 Hz to 110 kHz, the noise floor is -160 dB, dynamic range exceeds 120 dBA and THD+N is 0.003% at 1 kHz and 1 W. Inputs are one RCA pair with 3.6 kOhm impedance and one XLR pair with 7.2 kOhm, and WBT speaker terminals and trigger input and output are fitted. Consumption is 0.5 W in standby and 19 W at idle. The amplifier measures 440 x 120 x 400 mm and weighs 18 kg.

Engineering and use context

The input buffer uses pure Class A polarised bipolar transistor stages, and the output stage is built from Extraudio's EPAM amplification modules, which the company describes elsewhere as Class AD. Switching output stages of this kind explain how such power fits into a slim and relatively light chassis with a low idle draw. A separate supply feeds each channel, so left and right do not share current reserves, and the fully balanced circuit carries each channel as two opposite-polarity signals. The high damping factor points to a very low output impedance at the speaker terminals. Energy-efficiency control software manages consumption, and the amplifier complies with Energy Star and the ErP 1275/2008/EC standby regulation. The chassis is 6000-series aeronautical aluminium, finished in black, white or grey with a ceramic coating and epoxy varnish. The relatively low input impedance is best driven by a preamplifier whose own output impedance is low.

Pairing

With its power reserve, the XP-A1500 MKII drives any loudspeaker, including very inefficient and low-impedance designs. A solid-state preamplifier with low output impedance and balanced outputs is the best source, such as Extraudio's own XP5 preamplifier.

Alternatives

The Extraudio XP-A800 is the smaller power amplifier from the same Extraudio range of the period.