Unison Research Unico 150 Hybrid Stereo Integrated Amplifier at Vinyl Sound Buffalo, NY USA

The Unico 150 is a hybrid stereo integrated amplifier from Unison Research (Treviso, Italy), available at Vinyl Sound in Buffalo, NY, USA. A What Hi-Fi? reviewed amplifier described as "something of a powerhouse" delivering "an immensely muscular sound mixed in with a large dose of fun," the Unico 150 is Unison Research's most powerful hybrid integrated design. Using a three-stage topology -- a pure Class A ECC83 totem-pole input stage, a pure Class A 6H30 totem-pole driver stage, and a Class AB MOSFET complementary output stage -- the Unico 150 delivers 150 watts per channel at 8 ohms and 220 watts per channel at 4 ohms, with zero global negative feedback and a THD below 0.15% at 1 kHz at 1 watt. Six line inputs (including two balanced XLR) and a subwoofer output with volume control make the Unico 150 a hub for complex high-end systems.

Three-Stage Hybrid Topology with Zero Global Feedback

The Unico 150's circuit architecture is defined by three distinct gain stages, each optimized for a specific function. The input stage uses an ECC83 double triode in a totem-pole Class A configuration, establishing the amplifier's tonal character entirely through the tube stage -- the "character" of the amplifier, as Unison Research states, is entirely determined here. The driver stage uses a 6H30 double triode -- a high-transconductance Russian-designed tube used by Audio Research and Balanced Audio Technology in reference preamplifier designs -- in a parallel totem-pole Class A configuration. The output stage comprises four pairs of complementary MOSFET Hexfet devices per channel in a thermostable Class AB configuration. Global negative feedback is zero (0 dB), with only 16 dB of local feedback applied within stages; this preserves the open, immediate quality of the tube input stage without the constraint of a feedback loop encompassing the full amplifier. Output resistance is below 0.4 ohms across the full audio band.

Power, Connectivity, and Practical Design

At 150 watts into 8 ohms and 220 watts into 4 ohms, the Unico 150 can drive virtually any loudspeaker to any listening level in any room. The six inputs include three unbalanced RCA, two balanced XLR, and one bypass unbalanced input for home theater pre-out integration -- allowing the Unico 150 to serve simultaneously as a two-channel music amplifier and a home theater front-left/front-right amplifier. A tape output and a subwoofer output with volume control extend the system integration capabilities further. The bi-wiring output connectors accommodate four pairs of binding posts (4+4) for bi-wired or bi-amplified loudspeaker connections. THD remains below 0.35% at 1 kHz at 100 watts and below 0.9% across the full 20 Hz to 20 kHz bandwidth at the rated 150-watt output -- specifications that compare favorably with many all-solid-state designs at this power level.

Key Features

• 150 W/ch (8 ohm) / 220 W/ch (4 ohm): High output power from a hybrid tube/MOSFET topology capable of driving any loudspeaker to reference listening levels.
• Zero Global Feedback: No global negative feedback loop preserves the open, tube-like immediacy of the ECC83 input stage across the full output power range.
• ECC83 Input Stage + 6H30 Driver Stage: Pure Class A tube gain and driver stages determine the amplifier's tonal character, with the MOSFET output stage providing power and current delivery.
• Three Balanced XLR-Compatible Inputs: Two balanced XLR inputs and three unbalanced RCA inputs plus one bypass unbalanced input for home theater integration.
• Subwoofer Output with Volume Control: Volume-tracked subwoofer RCA output for powered bass supplement integration without a separate preamplifier output.
• What Hi-Fi? Reviewed: Described as "something of a powerhouse" delivering "an immensely muscular sound mixed in with a large dose of fun."
• 4+4 Bi-Wiring Output Connectors: Eight binding posts per channel accommodate bi-wired or bi-amplified loudspeaker connections.

Technical Specifications

Frequently Asked Questions

What is the Unison Research Unico 150?

The Unison Research Unico 150 is a hybrid stereo integrated amplifier from Treviso, Italy, using an ECC83 tube input stage, a 6H30 tube driver stage, and a MOSFET Class AB output stage to produce 150 watts per channel at 8 ohms and 220 watts per channel at 4 ohms. It operates with zero global feedback, six line inputs including two balanced XLR, and a volume-controlled subwoofer output.

How does the Unico 150 compare to the Unison Research Unico 90?

The Unico 150 uses a three-stage topology with a dedicated 6H30 driver stage between the ECC83 input and the MOSFET output, while the Unico 90 uses only two stages -- an ECC83 and ECC81 input stage driving the MOSFET output directly. The Unico 150 produces 150 W/ch at 8 ohms and 220 W/ch at 4 ohms, compared to the Unico 90's 100 W/ch at 8 ohms and 160 W/ch at 4 ohms. Both use zero global feedback. The Unico 150 is the more powerful and more complex design with the additional driver tube stage for greater current delivery to the MOSFET bank.

What is the 6H30 tube used in the Unico 150's driver stage?

The 6H30 is a high-transconductance double triode of Russian origin, produced to military specifications and used by premium preamplifier manufacturers including Audio Research, Balanced Audio Technology, and Conrad Johnson in reference-level designs. Its unusually high transconductance -- approximately three to four times that of an ECC82 -- allows the 6H30 to drive the gate capacitance of multiple MOSFET output devices with minimal phase shift or frequency roll-off. In the Unico 150, the 6H30 bridges the ECC83 input stage and the four-pair MOSFET output bank with a Class A driver that adds negligible distortion while maintaining the signal character established by the input tube.

Can the Unico 150 be used as a home theater front amplifier?

Yes. The Unico 150 includes a bypass unbalanced input that can be connected to the front-left and front-right pre-outputs of an AV processor or surround sound receiver. In bypass mode, the Unico 150's volume control is circumvented, and the AV processor governs output level -- a standard home theater bypass configuration. This allows the Unico 150 to serve simultaneously as the primary two-channel music amplifier and as the front-channel amplifier in a surround sound system.

Where can I buy the Unison Research Unico 150 in Buffalo, NY or the USA?

The Unison Research Unico 150 is available at Vinyl Sound in Buffalo, NY, USA. Vinyl Sound is an authorized Unison Research dealer serving western New York and the broader United States. Contact Vinyl Sound for current availability and system-matching advice.