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Ferrum OOR + HYPSOS

Name: Ferrum OOR + HYPSOS
Brand: Ferrum
SKU: oor-hypsos
Rating: 4.5 (2 reviews)

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OOR can be upgraded with HYPSOS Hybrid Power System using our proprietary Ferrum Power Link (FPL) connection, making both units perform to their highest levels. While OOR performs very good right out of the box, it is made to excel above and beyond when used together with HYPSOS. Using the FPL connection means HYPSOS can measure far deeper inside OOR than it can with any other product. Not only does HYPSOS work better in this combination, OOR will also perform even better than it normally does. The truly balanced design of the preamplifier stage coupled with the discrete power amplifier technology in combination with the implementation of highly selected components is elevated to a level of its own.

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Overall Score 90/100

Deliciously Crispy

Ferrum OOR + Hypsos

Ferrum OOR + Hypsos pairs the compact, high-current OOR headphone amplifier with the award‑winning Hypsos power supply to prioritize clarity, authority and a whisper‑quiet background. As noted by Andrew Everard in HiFi News, the OOR delivers a balanced, transparent and highly revealing presentation with generous, extended bass, incisive midrange and articulate treble, producing a spacious, precisely imaged soundstage. Performance highlights include huge dynamics, very low distortion and the ability to drive demanding headphones in balanced mode, thanks to a fully balanced signal path and both 4‑pin XLR and 6.35mm outputs. The chassis is compact and smart though a little functional in finish; the Hypsos adds variable voltage and sonic refinement. Ideal for desktop listeners and two‑channel users seeking detailed, energetic playback, the OOR + Hypsos is a performance-focused pairing in its price band.

HiFi News

"the OOR will redefine the category of headphone amplifiers… [it] will drive any headphones effortlessly to the max of their potential, while preserving the essence of the music it amplifies"

Pros

Transparent, highly revealing presentation with generous, extended bass and precise imaging.
Huge dynamics and very low distortion, delivering strong transient authority and a near‑silent background.
Fully balanced signal path with both 4‑pin XLR and 6.35mm outputs and Hypsos power-supply options for refined drive and compatibility with demanding headphones.

Cons

Relatively sparse feature set (no remote) and a cautionary bypass function that can be risky if used improperly.
Finish is smart but somewhat utilitarian, with exposed screw‑heads noted in the construction.

Sound Quality

92/100

Reviewer emphasizes 'huge dynamics', 'superlative control and authority' and the amp's ability to 'instantly unleash all their power', showing excellent transient response and headroom. Multiple musical examples are cited where the amp conveys punch and ambience convincingly.

Noise Floor

90/100

The review repeatedly references 'ultra-low distortion', 'reducing distortion to inaudible levels' and 'zero fatigue', implying a very quiet, near-black background suitable for sensitive cans. No audible hiss or noise complaints are mentioned.

Headphone Compatibility

90/100

The OOR is described as able to 'drive any headphones effortlessly' and is tested driving Oppo PM-1 in balanced mode; the signal path is balanced throughout. While exact output impedance and wattage aren't given, reviewer language and balanced outputs indicate excellent practical compatibility.

Build Quality

84/100

Construction is described as 'smart but a little functional' with 'exposed screw-heads', and the in-house amplification design is noted. The finish is solid but not ultra-luxury, and the supplied 24V plug-top PSU suggests a practical rather than fully bespoke approach.

Features Connectivity

84/100

Provides balanced (4-pin XLR) and single-ended (6.35mm) headphone outputs and RCA inputs (converted to balanced internally). No DAC or digital inputs are mentioned; having both balanced and SE outputs and the balanced signal path justify an above-baseline score.

Value for Money

86/100

Review mentions a price point (£1,995 for the OOR) but offers no explicit value judgment; given the lack of direct pricing commentary, a neutral baseline score is applied. The amp's high performance is evident, but reviewers do not frame cost vs alternatives explicitly.