Усилители мощности моно — Chord ULTIMA 2

The ULTIMA 2 is a 750 W mono amplifier from the British company Chord Electronics, introduced in 2019 as part of the company's 30th anniversary celebrations. It carries over the topology of the range-topping ULTIMA at a lower cost and is a direct replacement for the earlier SPM 6000 MKII. Chord says the model shares the DNA of its bigger sibling and uses the very latest amplifier technology of the company, and like the rest of the full-size range it is made by hand in Britain with a 5-year warranty.

Key specs that matter

Into 4 ohm the rating climbs to 1,305 W RMS, and THD is given as 0.005%. Noise is better than -89 dB relative to signal, and gain is 30 dB. Chord quotes a frequency response of -1 dB from 0.2 Hz to 46 kHz and -3 dB from 0.1 Hz to 200 kHz. Input impedance is 100 kOhm for balanced and unbalanced connections, with an output impedance of 0.04 ohm. At full power the amplifier draws 3,000 W, and in standby it needs 10 W. Height is 18 cm with the included Integra legs and 15 cm with the optional gloss black acrylic side blocks, while width is 48 cm or 42 cm respectively. Weight is 41.15 kg.

Engineering and use context

Proprietary Chord MOSFETs in the output stage operate in sliding-bias Class AB, supplied by an HF switch-mode power supply, and a dual feed-forward error correction scheme is used. Circuitry is fully balanced, and the amplifier is convection cooled. The remodelled fascia by designer John Franks is a 28 mm thick piece of precision-machined aircraft-grade aluminium. A recessed spherical power button in polycarbonate glows whenever the unit is on or in standby, while lighting brightness is reduced with a concealed control on the fascia. Inputs comprise one balanced XLR inverted, one balanced XLR non-inverted, one gold-plated RCA inverted and one gold-plated RCA non-inverted socket, plus a 12 V trigger input for Chord's auto start. Bi-wiring is supported by two sets of gold-plated loudspeaker binding posts rated for high current, and mains enters through a C-19 IEC connector. Finishes are Jett Black or Argent Silver, and the stackable Integra legs are offered in three colours - Jett Black, Argent Silver and Nickel.

Pairing

Each ULTIMA 2 powers one channel, so stereo playback needs two of them. The inverted inputs let the amplifier take a phase-inverted feed on the balanced as well as the RCA connections.

Alternatives

A more compact model in the same mono range is the Chord ULTIMA 3, rated at 480 W RMS into 8 ohm with a depth of 36 cm.