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Unison Research Simply 845: Hi-Fi Products We Covet For 2024

What will we be reviewing in 2024? Some early thoughts on the Unison Research Simply 845 Integrated Amplifier.

Unison Research Simply 845 Integrated Tube Amplifier

Thou shalt not covet thy neighbour’s tube amplifier.

Even if it provides much needed light and warmth in a very dark time.

2023 was not a good year. Certainly not for my family and close friends in Israel. Regardless of when and how the conflict concludes, our future will be on the other side of the pond; that change will provide me with the opportunity to offer a very different perspective on all of this with most of Europe only a few hours away by plane.

Italy, Serbia, Croatia, Romania, Hungary, and Poland will be part of my coverage area starting in late-2024 and that will include some interesting visits to smaller companies making some rather unique tube components and loudspeakers that you may not be aware of.

Having owned 7 tube amplifiers over the past 30 years, my affection for them remains rather strong but is also tempered by the reality that they require a different level of maintenance and that one must always have some replacement tubes handy.

Supply chain issues have also made tubes more expensive and that is certainly true in regard to 300B and 845 output tubes.

Unison Research Triode 25 Integrated Amplifier Angle
Unison Research Triode 25 Integrated Amplifier Angle

Having already reviewed the excellent Unison Research Triode 25 Integrated Amplifier in 2022, I was rather curious to experience the next level of their products; albeit through a system well out of my price range.

The Unison Research Simply 845 caught my attention at CAF 2023 and it was a room that I returned to because it demonstrated an ability to handle both ends of the spectrum so well.

Delicate and quiet passages floated in the middle of the room and lingered just long enough for me to lean forward in my chair and absorb them.

Jazz trios with strong bass accompaniment felt rock solid and rich with texture; horns had wonderful bite and color and I walked out of the room to find Steve Jain and book some quality time with this amplifier.

Unison Research Simply 845 Integrated Tube Amplifier Front
Unison Research Simply 845 Integrated Tube Amplifier

The Simply 845 utilizes a pair of 845 tubes in a single-ended configuration that outputs 23 watts of Class A power. 

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The amplifier uses handmade in-house custom transformers, ECC82/12AU7s in the preamp stage and an ALPS RK27 motorized volume control; the unit is also self-biasing so all one needs to do is install the tubes and the unit takes care of the rest. 

4 line level inputs and 2 sets of outputs (1 subwoofer, 1 tape) for those keeping score; one does need to add their own external phono stage for vinyl playback.

The 67 pounds of metal and wood are housed in a rather compact 14 1/2″ x 10 1/4″ x 22 1/2″ chassis.

Unison Research Simply 845 Integrated Tube Amplifier Angle

Little Boxes Made of Ticky Tacky…

With the Simply 845 booked for the end of January, I have some time to find a few loudspeakers that might offer some compelling system options; the Q Acoustics 5040, Opera Callas Diva, and the DeVore Fidelity O/baby Loudspeakers are likely to be my primary focus with the amplifier.

The O/baby use a horn-loaded .75″ textile dome tweeter and a new 7″ woofer using the same uncoated German paper as the O/96 and O/Reference.

DeVore Fidelity has worked with SEAS for the past decade on the drivers for the Orangutan Series and the O/baby continues that successful relationship.

Unlike other DeVore designs, the O/baby have a sensitivity rating of 90 dB (8 ohms) and seem like an easier load.

Devore Fidelity O/baby Loudspeaker right angle at T.H.E. Show
Devore Fidelity O/baby

The O/baby are not large loudspeakers (14.75″ w x 9.75″ d x  35″ h including optional stands) — and they definitely don’t sound like they appear. 

Having listened to the O/baby at one show and three times at local dealers, I am convinced that the Simply 845 will prove to be an excellent match.

The Opera Callas Diva are 90 dB/2.83 Volt/1 meter, which on paper seems less like a decent match for the Simply 845; with the exception of the impedance that falls to 3 Ohms.

Having already listened to the combination at the show, it would be accurate to state that it handled jazz and chamber music extremely well — but that represents only a fraction of the music that I enjoy and it will be interesting to see how it handles far more demanding material.

Having settled on the Cambridge Audio Edge A ($6,499) as my solid state reference for the next decade or more, the Unison Research Simply 845 has an opportunity to earn a spot in our shipping container and my rack overlooking the Mediterranean in 2025.

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