Интегральные усилители — Aries Cerat Protos

The Ianus Protos is an Aries Cerat integrated amplifier with a single-ended TriodeFet output stage, priced at GBP 24,450 in the UK, or HKD 240,000 according to a 2024 Hong Kong press release. It belongs to the Ianus series alongside the Aperio integrated, and it pairs a single amplifying stage with a separate power supply chassis.

Key specs that matter

Output is 20 W into 8 ohms in Class A. The tubes are two 6J11P-E, and the E280F, E282F, E810F, E180F and D3A types are compatible. Maximum gain is 18 dB. Volume is set by a 61-step relay-switched resistor ladder, which can be bypassed. Noise is -90 dB referenced to 1 V, and full power is available down to 5 Hz at -3 dB. There are five RCA inputs, and a 4-pin XLR socket provides a balanced headphone output fed directly by the output stage. The main unit measures 500 x 490 x 170 mm and weighs 60 kg, and the power supply measures 190 x 310 x 70 mm and weighs 5 kg.

Engineering and use context

Aries Cerat first presented the Protos in Munich in May 2023. Its name means the first, as Aries Cerat calls it the smallest application of its TriodeFet technology. It shares a common circuit core with the Aperio, but the power supply and many parts are designed differently. Aries Cerat describes the TriodeFet active element as combining high linearity, high voltage gain, high current gain and very high input impedance, which is what allows the whole path from input to speaker terminals to run through one stage. Unlike a single-ended amplifier with large output tubes, the design is described as practically maintenance free, since the small tubes that shape the transfer curve are rated for more than 10,000 hours. The resistor ladder takes the place of the multitap transformer volume control used in the bigger Aries Cerat models.

Pairing

The output rating points to high-sensitivity loudspeakers in rooms of about 20 m2. The RCA inputs cover a DAC, a phono stage and other line sources, and with the volume bypassed a separate preamplifier can control the level. Compared with the Ianus Aperio, the Protos has 15 W less output, 3 dB less maximum gain and a main unit that is 20 kg lighter. Balanced headphones plug into the 4-pin XLR socket, so no separate headphone amplifier is required.

Alternatives

The Aries Cerat Genus is an 845 single-ended integrated amplifier with 25 W in Class A1, four RCA and one XLR inputs and a 67 kg chassis.