UNISON RESEARCH S6

Pre owned. In excellent condition. Free from any visible signs of wear. Not supplied with original packaging.

The Unison Research S6 is a fully tube-based stereo integrated amplifier, designed and built around a Class A configuration. The power stage uses a parallel single-ended ultralinear circuit with the tubes connected in parallel, while the entire amplification circuit is built using discrete components.

The tube stage comprises a total of eight tubes: two ECC82 tubes used as driver tubes and six Electro-Harmonix EL34 tubes used in the power stage. The EL34 tubes can also be replaced with 6CA7EH tubes, maintaining the same type of operation in the output stage.

The Class A output-stage configuration and the use of EL34 tubes define the amplifier's operating architecture, while the discrete circuit design avoids the use of integrated circuits in the amplification stage.

The updated version of the S6 introduces a renewed aesthetic and a redesigned mechanical structure. The wooden front panel, featuring contrasting inlays, houses the electronics in a design that reflects Unison Research's Italian construction tradition.

The amplifier features five line-level inputs for connecting analog sources such as CD players, DACs, streamers and other line-level electronics, together with a dedicated Tape output for connection to a recorder or compatible device.

The S6 is designed for use with conventional loudspeakers and, with its 35 W per channel of Class A power, is suited to loudspeakers with good efficiency.

Technical specifications:

• Type: tube stereo integrated amplifier
• Tubes: 2 × ECC83; 6 × EL34, with adjustable bias for each power tube
• Output stage: parallel single-ended; ultralinear
• Operating class: pure Class A
• Output power: 35 W/channel
• Frequency response (-1 dB): 20–30,000 Hz
• Impedance: input 47 kΩ; output 6 Ω
• Inputs: 5 × line-level
• Outputs: 1 × Tape
• Power consumption: 265 VA max
• Dimensions (W × H × D): 350 × 210 × 490 mm
• Weight: 25 kg