Pathos Classic One Mk 3 review

Affordable hero fares well against its higher-priced competitors

TechRadar Verdict

Marrying all the strengths of classic valve and solid-state amps would be a tall order, but this attractive amp gets close, offering beautifully musical presentation with good tonality and detail. Warmly recommended.


  • +

    Appealing design

  • +

    Precise volume control

  • +

    Good tonality and detail


  • -

    Some bass issues

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There are valve amps and there are solid-state amps and there are hybrids, which combine both technologies.

Pathos specialises in the last type and while the company's proprietary 'INPOL' configuration is reserved for upmarket models, this more modest unit still combines small-signal valves with power MOSFET, not to mention bipolar transistors in between.

Charming design

There are plenty of unexplored possibilities in this direction and we're happy to see people investigating some of them.

The appearance has plenty of old-style valve amp about it, and we find those little cages over the two valves rather charming, but the overall effect can seem a little fussy.

Behind the red capacitors, a slotted metal cover distinctly reminiscent of a valve cage covers a heatsink which carries, on its bottom face, one pair per channel of MOSFETS.

They and the rest of the circuitry, are attached to a circuit board, which occupies most of the internal space with a small separate board carrying input and output sockets and also the input selection relays.

Precise volume control

The Classic One uses an electronic attenuator for volume control, giving accurate half-dB steps from full volume down to inaudibility.

It makes volume adjustment a little slow, but the digital display means you can find your preferred setting easily. That display is shared by the input selector and, in normal use, there's nothing to show which input is in fact active. One of the five inputs is balanced.

Although components are not extravagant, there are some nice touches in this unit such as the use of non-magnetic stainless steel for the chassis and a pair of very upmarket op-amps in the circuit.

Smooth operator

Few of the comments on this amp suggest that it is qualitatively different from any others in any particularly solid-state way. On the contrary, its big sound picture and generally smooth presentation are very much classic valve characteristics.

Although its attack was thought to be among the best, it is not necessarily the very pinnacle among its peers and bass control attracted a little mild criticism.

Perhaps the treble is the most 'transistorised' area. It is just a touch bright, but its extension is welcome and gives a good shimmer to delicate sounds like small percussion instruments and a real sense of acoustic 'air' to well-miked recordings.

Unfussy presentation

Very low bass is good, extended and tuneful and this served the orchestral track well and also the Miles Davis. The bass control issues apply mostly to the higher bass regions, making rhythm occasionally a little unclear.

Detail is also very good. In fact, we were very taken with the way the Classic One presents detail; unfussy and, on the whole, playing second fiddle to the overall musical picture.

Imaging is broad but not ultra-precise, a trade-off we found pleasant. Pathos does indeed seem to have achieved a marriage between valves and transistors which is sonically biased towards the former.

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