The Fosy Audio Mamoritai Euphony headphone amplifier is a surprising revelation. From a company known for its budget-friendly Amazon products, the Euphony represents a dramatic leap forward, boasting a stunning $2,000 price tag and a meticulously crafted chassis that belies its origins. This isn't just a price increase; it's a complete reimagining of Fosy Audio's design philosophy, a bold move made in collaboration with Mamoritai. Initial skepticism, fueled by past Kickstarter experiences, was quickly replaced by admiration for the Euphony's refined aesthetics and build quality.Despite its high price, the Euphony takes a minimalist approach to its feature set. However, this simplicity belies the amplifier's true strength: its internal flexibility. Featuring socketed op-amps, users can swap between included options, tailoring the sound to their precise preferences. This level of customization, combined with exceptional detail retrieval and dynamic range, makes the Euphony a compelling option for discerning audiophiles seeking a truly personalized and high-fidelity listening experience.
Pros And Cons
- Clean and nicely designed interior
- High level of detail and resolution
- Dynamic sound delivery
- Sufficient power for demanding headphones
- Good volume pot with minimal channel imbalance
- Usable volume range with various headphone sensitivities
- Adequate performance as a preamp
- Relatively few features for the price (no gain switch on the front)
- Higher cross-talk than some other amplifiers, resulting in a narrower soundstage
- Gain switch is located internally
- Advertised power (1200mW) seems to be a peak measurement; realistically around 800mW
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An Unexpected Collaboration: Fosy Audio's High-End Venture
The Mamoritai Euphony headphone amplifier, a surprising release from Fosy Audio, a company known for its budget-friendly Amazon offerings, presents a significant departure from their usual product line.
This $2,000 amplifier boasts a stunning, highly polished chassis, a striking contrast to their previously more utilitarian designs.
The collaboration came as a surprise, with initial hesitation due to past Kickstarter experiences, but Fosy Audio's established presence and apparent upgrade in design aesthetics made the partnership more appealing.
Features and Design: Minimalist Aesthetics, Customizable Internals
Despite its high price point, the Euphony lacks some features typically found in similarly priced amps. It features a simple design with a volume control and a non-switchable preamp output.
However, it offers unique internal customization. The amplifier includes socketed op-amps (operational amplifiers), allowing users to swap between the included Muses O2 and the upgrade SparkOS op-amp for a distinct sonic signature.
This internal flexibility allows for a level of personal tuning not often seen in pre-assembled units, appealing to audiophiles who want to refine the sound to their precise preferences.
Power and Performance: Sufficient Muscle for Demanding Headphones
The Euphony boasts a power output of around 800mW, which might seem modest compared to some competitors. However, its generous capacitance ensures ample power for even highly demanding headphones.
The reviewer tested the amplifier with various headphones, including the Susvara and Dan Clark Audio models, finding the power output more than adequate for a satisfying listening experience, even at higher volumes.
The reviewer also notes that the bass frequencies will distort first under high load, which is expected behavior due to the higher energy requirements of lower frequencies, and this is not necessarily a fault of the amplifier.
Sound Quality and Listening Impressions
Using the Chord TT2 and mScaler as sources, the Euphony delivered exceptional detail and resolution, maximizing the potential of the TT2’s capabilities.
The reviewer notes a slightly narrower soundstage compared to balanced amplifiers, resulting in a more intimate and punchy sound, which is subjective and may appeal to certain listeners.
The upgrade to the SparkOS op-amp significantly improved the sound quality, offering greater clarity and dynamics, making it sound like a true high-end amplifier.
Conclusion: A Surprisingly Excellent Amplifier, But With Caveats
The Mamoritai Euphony is a surprisingly capable headphone amplifier, offering excellent detail, resolution, and dynamic range. Its internal op-amp swappability offers impressive customization.

While its power output and minimalist feature set might seem modest for its price, the robust design and superior sound quality justify its cost for those seeking a refined listening experience.
The slightly narrower soundstage and lack of front panel gain control might be deterrents for some, but overall, it's a high-quality amplifier that performs well above its expected price point.