Unison Research Unico 150

150 watts with a tube heart. The Unico 150 was not designed as a solid-state amplifier with tubes added for warmth — a common approach that produces hybrid amplifiers with solid-state character and a vague approximation of tube coloration. The two tube stages here are the circuit's sonic foundation. Everything else exists to amplify what they establish.

The Circuit

ECC83 at the input stage, operating in pure Class A. 6H30 at the driver stage, also operating in pure Class A. Both directly coupled to the HexFET output stage, which provides the current and power that speakers require. Zero global negative feedback throughout.

The ECC83 is a high-gain, low-noise triode — the correct choice for an input stage where the signal is at its most delicate. The 6H30 is a Russian-designed dual triode with exceptional linearity and drive capability, used in the top preamp and amplifier designs from both western and Russian manufacturers. Together they establish the sonic character of the amplifier before the signal reaches the HexFET devices.

Direct coupling between stages eliminates the capacitors that would otherwise decouple the tube stages from the solid-state output — capacitors that are convenient but that introduce their own colorations and bandwidth limitations. Direct coupling requires precise engineering to avoid DC offset, and Unison Research handles it correctly.

The Result

Bass authority that surprises people who have expectations about what a hybrid amplifier delivers. Midrange with the dimensional quality and harmonic richness of the tube input stage. High-frequency extension that is extended without being mechanical. This is what a well-designed hybrid amplifier sounds like when the tube stages are doing genuine work rather than decorative duty.

Press Recognition

The Unico 150 has been reviewed by Hi-Fi+, Hifi News, and Stereophile. Hi-Fi+ called it one of the finest hybrid integrated amplifiers at any price, with bass performance that rivals dedicated solid-state designs and midrange that tube amplifier owners will recognize immediately.

Specifications

• Output power: 150 watts per channel
• Input stage: ECC83, Class A
• Driver stage: 6H30, Class A
• Output stage: HexFET
• Coupling: Direct, no coupling capacitors between stages
• Feedback: Zero global negative feedback
• Origin: Handcrafted in Italy

Authorized Unison Research dealer. Questions about speaker matching, or how the Unico 150 compares to the Unico 90 or DM v2 for your specific situation? Reach out.