Предусилители — Esoteric Grandioso C1X

The Grandioso C1X is a two-chassis preamplifier from Esoteric of Japan, with the control and amplifier unit in one box and a 29 kg linear power supply in another. Esoteric describes it as two monaural preamplifiers combined into one set of components.

Key specs that matter

Three XLR input pairs are fitted that can each run as ES-Link Analog at 50 kohm, and two RCA pairs at 68 kohm. Inputs accept up to 12 V at a sensitivity of 500 mV. Outputs are two XLR pairs and two ES-Link Analog pairs, all at 30 ohm, with a rated output of 2 V and a maximum of 17 V. Gain is +12 dB. Esoteric quotes 1 Hz to 150 kHz at -3 dB, 120 dB S/N A-weighted with a 2 V input, and 0.00035% THD. The main unit measures 445 x 132 x 449 mm and weighs 20.2 kg, while the supply is 445 x 132 x 452 mm. Each channel draws 15 W.

Engineering and use context

Volume uses the Ultra Fidelity Attenuator System with the UFA-1792 module, giving 1,120 steps of 0.1 dB, where the original Grandioso C1 offered 100 steps of 0.5 dB. Gain stages are built from the IDM-01 Integrated Discrete Amplifier Module. The outputs are driven by parallel HCLD buffer amplifiers with a slew rate of 2,000 V/us, backed by EDLC super capacitors of 250,000,000 uF per channel placed near the buffers. Instead of relays, FET switches carry 3 A rated and 12 A peak current. Signals stay in a fully balanced hot and cold layout, RCA inputs are balanced right after entry, and a copper bus bar on the input board limits crosstalk. Left and right remain separate from the inputs to the DC supply, which has two AC cords and five large transformers along with Schottky diodes. Transformers and boards sit on separate chassis layers with laser-cut slits and pinpoint feet. Logic control is isolated by a photocoupler and shuts down between operations. Input gain is adjustable by 18 dB and balance by 6 dB, both in 0.1 dB steps, and an AV through mode, RS-232C, one trigger input and two trigger outputs are provided.

Pairing

Esoteric names the Grandioso K1X SACD player and the Grandioso D1X D/A converter as ES-Link Analog sources for an all-Grandioso X system. The two output sets can feed several power amplifiers for bi-amp or multi-amp systems, and the ES-Link Analog outputs can be changed to RCA as an option.

Alternatives

The Esoteric Grandioso C1X solo puts a dual balanced preamplifier and its supply into a single 27.5 kg chassis.