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Unison Research Triode 25 Integrated Valve Amplifier and DAC


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Enquiry/price check? Click here SKU: UNRTRD25IVD
Ex VAT: £3,165.83

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Condition: Brand new in original retail packaging

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Warranty length 1 Year (2 Years on registration)
Brand Unison Research

Tech Specs

- Output Stage: Push-pull, ultralinear, Class-AB
- Output Power: Approx. 45 watt per channel in Ultralinear (Pentode) configuration. Approx. 25 watt per channel Triode configuration
- Output Impedance: 6 Ohm
- Input: 4 Linea ( 1 Tape ) , 1 USB DAC
- Input Impedance: 47 kOhm / 50 pF
- Output: 1 Tape out, 1 Sub Out
- Negative feedback: 5 dB or 1.8 dB
- Valve complement: 2 x ECC83, 1 x ECC82, 4 x EL34
- Power Consumption: 300 watt max
- Dimensions: 30 cm x 45 cm x H. 20cm
- Net weight : 20 Kg

Product Description

Unison Research Triode 25 is an integrated valve amplifier and DAC, born out of the huge success of the long-standing Triode 20 amplifier and released to mark the 25th anniversary celebrations of Unison Research's formation. It's been developed over an extended period to ensure it is a worthy successor to the Triode 20's name.

Based on Triode 20

Like its predecessor, the Triode 25 is a push-pull amplifier that utilizes EL34 tubes in the output stage. The push-pull circuit includes a final stage with two power tubes intended for the amplification of the audio signal, and is then followed by a symmetrical output transformer stage that reconstructs the signal into a high-quality linear wave.

Push/Pull Configuration

Using a push-pull structure in this amplifier design allows for numerous benefits including higher-output power compared to single-ended designs, improved efficiency and no static polarization of the output transformer for greater performance in the output section.

However, for this to work well it is essential that all the individual amplification stages are carefully designed and constructed to prevent the formation of dangerous and compromising odd-order harmonic distortion. This is true for the two semi-output amplifiers, and even more important in the output transformer.

Two Modes

The Triode 25 can operate in two modes: triode and pentode. The latter is capable of delivering a maximum power output of over 45 watts per channel (6Ω load) with minimal harmonic distortion across the entire audio band.

USB Input

The addition of a USB input modernises the Triode 25 and increases its appeal to the growing world of computer audiophiles, who use their laptop or computer as a high-quality audio source for their hi-fi. The USB input is 32-bit/384kHz and DSD 128 compliant to support the latest standards in studio quality audio.

Key Features

- Push-pull integrated valve amplifier
- 32-bit, DSD-compatible USB in for PC streaming
- Switchable Triode and Pentode modes
- Premium design throughout
- Locally sourced materials
- Based on the long-standing Triode 20 design
- EL34 tubes in the output stage
- RC2 remote with black wood finish included
- Premium Cherry Wood front panel

Please Note: Black finish is available through special order only.

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Contact Details

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0121 224 7350/7351

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0121 224 7300/7401

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07706 203859

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