Предусилители — Unison Research UNICO PRE

The Unico Pre is a hybrid stereo preamplifier from Unison Research, with its address on via Barone at Dosson di Casier, Treviso. The company says it came out of an intensive engineering study with the goal of top performance and easy integration with any audio system. Its front panel follows the two-element composition used on the other upper models of the Unico line, and the case was designed to the same standards of solid build and careful construction that the brand applies across its production.

Key specs that matter

Input sensitivity is 250 mV and input impedance is 10 kohm. Frequency response is flat at 10 Hz and falls by only 0.3 dB at 100 kHz. Signal-to-noise ratio is 95 dB, and total harmonic distortion is 0.01% measured at 3.14 V output and 1 kHz. The circuit runs with 0 dB of negative feedback, meaning no global feedback loop is applied. Maximum power consumption is 50 W. The case measures 43.5 cm by 43 cm with a height of 13 cm, and the net weight is 12 kg.

Engineering and use context

Two ECC82 valves, a type also known as the 12AU7, form a triode input stage running in Class A. The output stage is solid state and uses bipolar junction transistors, again biased in Class A. This division of work, with valves at the front and transistors driving the outputs, reflects the hybrid approach that defines the Unico series. The rear panel carries four line inputs that are available on RCA as well as XLR connectors, plus one RCA tape input. For the main signal there are two sets of RCA outputs and a single XLR output, joined by an RCA tape out and an RCA subwoofer out. Volume and source switching are also available from an infrared handset.

Pairing

Unison Research designed its Unico DM hybrid dual-mono power amplifier as the matching partner for this preamplifier. The DM has one XLR input and one RCA input, so the Unico Pre can drive it over either cable type. With two sets of RCA outputs, the preamplifier can also be connected to two power amplifiers at the same time, while the XLR socket serves an amplifier with balanced inputs. An active subwoofer connects through the dedicated subwoofer output, and a recorder fits into the tape loop.

Alternatives

The Unison Research Reference Pre is a dual mono valve preamplifier in two chassis, built as the partner for the Reference monoblocks.