Preamplifiers — Constellation Audio Revelation 2 Preamplifier

The Revelation 2 Preamplifier sits at the centre of the Revelation 2 series from Constellation Audio, with a British price of GBP 29,998. Constellation describes it as a condensed version of its top preamplifier designs, aimed at owners whose systems need a moderate number of inputs. The audio circuitry and the power supply are housed in two separate boxes, and the full-width main chassis comes in a champagne gold finish.

Key specs that matter

There are three stereo XLR inputs and three stereo RCA inputs, plus a USB port that is used for control only. Outputs are two stereo XLR pairs and two stereo RCA pairs, together with a 12 V trigger. Input impedance is 20 kohm balanced and 10 kohm single-ended, while the outputs present less than 50 ohm. THD+N stays below 0.001% from 20 Hz to 20 kHz at 2 V output and below 0.1% at 10 V output. Noise sits more than 105 dB down, A-weighted. Volume moves in 0.5 dB steps over a range from 0 dB down to -90 dB. The whole preamplifier weighs 16 kg, of which the external supply accounts for 5 kg, and that supply box measures 432 x 368 x 70 mm.

Engineering and use context

Gain comes from the Line Stage Gain Module, the same building block Constellation uses at the input of its amplifiers. It consists of fully balanced mirror-image circuits built with low-noise transistors matched by hand, while a servo loop monitors whether the positive and negative signal halves stay equal and trims any deviation. The external switch-mode supply is claimed to produce DC more than 20 dB quieter than conventional transformer designs. The layout is true dual mono - left and right channels are physically separated through the whole unit, including their own input and output sockets. Attenuation relies on a digitally controlled resistor ladder rather than a potentiometer, which keeps the left and right channels locked together at every setting. Operation is through an LCD touchscreen on the front panel or a remote control.

Pairing

With two pairs of XLR and two pairs of RCA outputs, the unit can drive two power amplifiers at once, and the trigger output switches a connected amplifier on together with the preamplifier. Revelation 2 Stereo and Mono amplifiers can take its signal through their Constellation Direct inputs, which skip one gain stage inside the amplifier, and the Revelation 2 Phono Preamplifier covers turntables, since this unit has no phono stage.

Alternatives

The Constellation Inspiration 2 Preamplifier offers the same input and output count in a single 11.5 kg chassis with its switch-mode supply built in.