Предусилители — Aries Cerat IANUS AGETO

The Ianus Ageto is a two-chassis valve line preamplifier made in Greece by Aries Cerat and belongs to the Ianus family of products. It was announced in 2021 and brought in the third generation of the company's TriodeFET technology, which pairs a redesigned circuit and driving configuration with a new Inverted Triode tube. One chassis carries the audio circuits and signal transformers, the other the power transformers, and each case measures 550 x 430 x 165 mm and weighs 70 kg, so the complete unit comes to 140 kg. The UK price of the Gen 3 version is GBP 57,450.

Key specs that matter

The input panel carries four RCA connections alongside a single true balanced XLR socket. Two gain settings are available - 3 dB in the low position with a maximum output of 2 Vrms, and 9 dB in the medium position with a maximum output of 4 Vrms. Input impedance is 7 kOhm below 100 Hz and output impedance is 12 ohm. Bandwidth is specified from 5 Hz to 300 kHz, and the noise floor is stated as better than minus 120 dB unweighted. Each channel uses one E280F driver tube and one Inverted Triode, and the Gen 3 design stays backward compatible with the Gen 1 version of that tube.

Engineering and use context

Attenuation comes from a 26-step transformer volume control built from a multitap input transformer and latching relays. Aries Cerat chose latching relays so that the currents that drive them cannot contaminate the audio signal, and left and right channel levels can be adjusted independently for balance. The input, volume and inter-stage transformers are wound on nano-crystalline cores. The power supply is true dual mono and sits in its own external chassis, so the power transformers are kept away from the signal transformers. Each channel has its own power transformer and eight independent choke-filtered supplies, one for each circuit of the preamplifier, and every channel is fed through its own high-gauge umbilical cord. According to the maker, the Inverted Triode offers a power bandwidth of 2 Hz to 500 kHz, against 15 Hz to 100 kHz for a conventional 300B tube.

Pairing

An HT bypass lets the preamplifier pass a fixed-level signal from a surround processor straight through, so a surround processor and the stereo sources can share one analogue front end. The unit is also compatible with the Aries Cerat HT Link.

Alternatives

Aries Cerat also builds the Impera II Ref, a preamplifier from its Impera range.