Усилители мощности моно — Aries Cerat Exsequor Reference

The Exsequor Reference is a tube monoblock power amplifier from Aries Cerat, supplied in pairs and now offered in MKII form. Aries Cerat describes the Exsequor as its top-level circuit topology in which an 814 tube drives a pair of 813 output tubes, and each channel is built as two stacked chassis. Both tube types are direct-heated thoriated tungsten designs. The UK list price for the MKII pair is GBP 94,950.

Key specs that matter

Output power is 65 W in class A1, and Aries Cerat states that this figure is available into both 8 ohm and 4 ohm loads. Voltage gain is x3, or 9.5 dB. Unweighted noise sits more than 100 dB down, and second harmonic distortion is -75 dB at 1 W and -55 dB at 10 W. Signal bandwidth runs from 8 Hz to 110 kHz at 80 per cent of maximum power. Output impedance is selectable by the user at 1.6 ohm on the 8 ohm tap, 0.8 ohm on the 4 ohm tap and 0.4 ohm on the 2 ohm tap. Each monoblock measures 610 mm wide, 590 mm deep and 525 mm high.

Engineering and use context

The 814 driver can deliver more than 14 W in class A to the grids of the 813 pair, and it passes that power through an amorphous double-C core inter-stage transformer with bifilar windings and a wide bandwidth. The supply is built around a 1,800 VA power transformer with 3,000 joules of energy storage. No capacitor sits in the audio path, while the driver and output supply rails rely on supercapacitors with an ESR of 1 milliohm. Bias for the tubes is adjustable during operation, with built-in digital monitors showing the operating point. Signal arrives through an RCA socket or through the AC link, a proprietary connection found on other Aries Cerat components. The same 814 and 813 tube line-up is also used in the smaller Concero 65 amplifiers, which the company presents as reduced versions of the Exsequor.

Pairing

Aries Cerat describes the class A1 output as able to drive most floorstanding loudspeakers, while the three output taps let the output to be matched to the rated impedance of the speaker. The AC link input connects to Aries Cerat sources and preamplifiers that offer the same link, and other preamplifiers connect through RCA. Within the brand, the Kassandra converters and the Talos phono stages supply the signal for a single-maker system.

Alternatives

The Aries Cerat Concero 65 Reference is a smaller mono pair with one 814 and two 813 tubes per channel, measuring 510 x 590 x 350 mm and weighing 95 kg per channel.