Предусилители — Dan D'Agostino Momentum C2

The Momentum C2 is a line preamplifier made by Dan D'Agostino Master Audio Systems which splits its circuitry across two enclosures, an audio chassis and an external power supply. The model sits in the Momentum range next to the C2Z, a variant with a FET output stage built to supply more current to Momentum Z power amplifiers, and it accepts an optional digital streaming module.

Key specs that matter

Three balanced XLR stereo inputs and one unbalanced RCA input are provided, together with two balanced XLR outputs. A 6.3 mm headphone socket sits behind a door in the front panel. Gain is 10 dB, input impedance is 1 Mohm and output impedance is 0.05 ohm. The maker quotes a frequency response of 0.1 Hz to 1 MHz at the -1 dB points and flat within 0 dB across 20 Hz to 20 kHz. Signal to noise ratio is above 110 dB A-weighted and above 120 dB unweighted, and distortion stays below 0.002%. The two boxes together are 432 mm wide, 226 mm high and 386 mm deep and weigh 33.1 kg, and buyers choose between silver and black.

Engineering and use context

The first gain stage is a discrete dual complementary differential design built around four JFET transistors in push-pull, an arrangement that raises input impedance and lowers noise. The maker describes the whole signal path as a complementary four-circuit topology, and the input can accept signal voltages of up to 30 V. Tone control circuitry and a separate headphone amplifier are built in. The power supply enclosure holds individual custom toroidal transformers for the analog and the digital sections, with filtering against RF noise and irregularities on the mains line, and it links to the audio chassis through gold-plated 30-pin interlocking connectors rated for 20 amps. Control comes from a two-way remote made of aluminium and Delrin, which uses Bluetooth and shows status on its own LCD screen.

Pairing

All the main outputs are balanced, so the natural partner is a power amplifier with XLR inputs, such as the stereo and mono models in the Momentum series. Owners who plan to stream can add the digital module, which brings coaxial, optical, USB-B, Ethernet and Wi-Fi inputs, decodes PCM up to 32 bit and 384 kHz as well as DSD256, and is Roon Ready with Tidal, Qobuz and Spotify integration. The single RCA input suits a phono stage or an older unbalanced source.

Alternatives

The Dan D'Agostino Progression Preamplifier is the line preamplifier from the brand's more affordable Progression series.