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[FS] Unison Research Triode 25 Valve Integrated Amplifier (with DAC)

Discussion in 'classifieds' started by Elephantears, Jan 22, 2023.

  1. Elephantears

    Elephantears Trunkated Aesthete

    The Unison Research Triode 25 is a 45W push/pull amplifier using 4 x EL34 power valves. I've tried several valve integrated amps and this one gave me the best combination of dynamic liveliness and tonal richness. It is especially good with Tannoys. Selling for £1500.

    Condition is fantastic. I hesitate to drop the M word (Mint), but it's in a beautiful state. Comes with a posh looking wooden remote control, valve cage, and original box. The input stage uses 2 x ECC83s and 1 x ECC82. All valves are the excellent modern Tung-Sol.

    Although it does have a very good double box, I would much prefer pick-up in SE London, or meet up somewhere nearby. I'd prefer the buyer to collect so I can demonstrate it in good working condition.

    It also comes with a very good built in USB DAC, and some useful options to allow you to tailor the sound.

    The Triode/Pentode switch gives you the option of a more dynamic neutral presentation (Pentode) or a more rich and saturated tone (Triode). I've tried amps with such switches that didn't really impress me (e.g. the Primaluna Dialogue Premium and Eastern Electric M520), but the switch on the Triode 25 is genuinely useful. It also has a choice of Negative Feedback options, so you can further tailor the sound.

    I generally used it in Pentode and the higher NFB setting, but there were times when I found Triode/low NFB a revelation. The great thing about this kind of flexibility is that not only can you tailor the sound to your choice of music and speakers, but also to how your ears are feeling today.

    Another important thing to note is that rather than having 4 and 8 Ohm taps, the Triode 25 is set at 6 Ohm. For me, this was a real benefit, as I've always found the 4/8 choice annoying and wished I could find the option in-between. I suspect the 6 Ohm setting may be one reason why it works so well with the Tannoys I've been using in recent years.

    [​IMG]IMG_3544 by eastmoran, on Flickr

    [​IMG]IMG_3545 by eastmoran, on Flickr

    [​IMG]IMG_3550 by eastmoran, on Flickr

    [​IMG]IMG_3555 by eastmoran, on Flickr

    [​IMG]IMG_3551 by eastmoran, on Flickr
    calorgas, Darren L, hifinutt and 2 others like this.
  2. Elephantears

    Elephantears Trunkated Aesthete

    Oh go on then, I'll bump it.
  3. Elephantears

    Elephantears Trunkated Aesthete

  4. Elephantears

    Elephantears Trunkated Aesthete

    Another weekend with valves? Can this be good for you?
  5. Elephantears

    Elephantears Trunkated Aesthete

    Still available.

    I've got an eBay seller offer so listing this today at a higher price than here.
  6. Elephantears

    Elephantears Trunkated Aesthete

  7. Elephantears

    Elephantears Trunkated Aesthete

    Look! Valves are emerging!
  8. Elephantears

    Elephantears Trunkated Aesthete

    Was looking for earliest uses of 'amplifier' in English: seems to be around 1570, to mean 'augment in volume or amount', but nothing in Shakespeare as far as I can see.

    No valves in Shakespeare either. Disappointing. But I suspect he would have used a valve integrated if they'd been available.
    anubisgrau likes this.
  9. Mark Packer

    Mark Packer All Rev'd up!

    Shakespeare is the epitome of analogue.
    anubisgrau likes this.
  10. Elephantears

    Elephantears Trunkated Aesthete

    'A valve is a device or natural object that regulates, directs or controls the flow of a fluid (gases, liquids, fluidized solids, or slurries) by opening, closing, or partially obstructing various passageways. Valves are technically fittings, but are usually discussed as a separate category. In an open valve, fluid flows in a direction from higher pressure to lower pressure. The word is derived from the Latin valva, the moving part of a door, in turn from volvere, to turn, roll.'
    anubisgrau likes this.
  11. Elephantears

    Elephantears Trunkated Aesthete

    Now reduced to £1450.
  12. Elephantears

    Elephantears Trunkated Aesthete

    If you have big Tannoys, you'll be amazed at the synergy with this amp: it has richness, swiftness, dynamics and finesse, all in the right balance.

    Bold Claim: I would put money on the Triode 25 against a Radford.
    Nagraboy likes this.
  13. Elephantears

    Elephantears Trunkated Aesthete

    To clarify after a question about the DAC. This was originally an optional extra, but I think it became standard. As mentioned it is USB input only, so you can get an almost one-box system here by just adding a Mac Mini or the like.
  14. Elephantears

    Elephantears Trunkated Aesthete

    Now £1395
  15. Elephantears

    Elephantears Trunkated Aesthete

  16. Elephantears

    Elephantears Trunkated Aesthete

    Ok, I'm going to bring this down to my minimum price - £1350. This is well below the average selling price for an immaculate example.
  17. Elephantears

    Elephantears Trunkated Aesthete

    I'll continue to occasionally bump but there will be no more price reductions. It's a beautiful amp, and Tannoy fans in particular owe themselves a hearing.
  18. Salamander

    Salamander pfm Member

    I cannot believe this amp has not sold, if I had not purchased a 300B amp last year I'd have had this in a shot.
    Good luck with the sale.

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