FiiO M23 Digital Audio Player Review

Digital audio players (DAPs) have evolved into an essential component of any serious audiophile’s portable setup. These versatile devices consolidate storage, digital-to-analog converters (DACs), and headphone amplifiers into a single, high-performance unit. While brands like Astell & Kern often dominate discussions in this category, FiiO has quietly built a reputation for producing feature-rich DAPs with remarkable value. One such standout is the FiiO M23 SS, the stainless steel variant of their latest digital audio player, priced at $899.99. This review offers a comprehensive analysis of the M23’s aesthetics, functionality, technical specifications, and real-world performance.

What Comes In The Box

The FiiO M23 arrives with a thoughtfully curated set of accessories, ensuring users can begin their listening journey immediately:

• M23 Digital Audio Player
• Pre-installed Screen Protective Film
• Protective Case (Dark Blue Aluminum Version)
• Leather Case (Silver Stainless Steel Version)
• USB-A Male to Type-C Female Adapter
• Tray Eject Pin
• GPL V2 Manual
• Warranty Card
• Type-C to Type-C Data/Charging Cable
• Quick Start Guide

Aesthetics and Build Quality

The M23 SS exudes sophistication with its polished stainless steel chassis, creating a visually striking and robust device. The reflective rear panel adds an almost transparent illusion, showcasing FiiO’s commitment to aesthetic finesse. While stainless steel tends to attract fingerprints, the included leather case mitigates this issue while preserving the player’s elegant appearance with a grille-back design. The unit’s substantial 392.3g weight conveys durability and suggests the powerful components housed within.

Ergonomically, the M23 features well-positioned tactile buttons that offer satisfying feedback. The volume control, in particular, is a highlight—combining a capacitive touch-sensitive slider with a physical button press, enabling precise adjustments. The device's 5.5-inch 720x1440 display is vibrant, offering crisp visuals and responsive touch functionality.

Software Interface and User Experience

Running on Android 10 and powered by the Qualcomm Snapdragon 660 processor, the M23 offers a smartphone-like user experience. Navigation is fluid and intuitive, especially for those familiar with Android devices. First-time users are greeted with a guided setup tutorial, facilitating a seamless introduction to the DAP’s features.

App compatibility is extensive, thanks to Google Play Store integration. Pre-installed applications such as Tidal and the FiiO Music app offer immediate access to high-fidelity streaming and local file playback. Multitasking between apps remains smooth, with 4GB of RAM providing sufficient headroom for various tasks.

Connectivity and Versatility

The M23 excels in connectivity, supporting both wired and wireless configurations:

Wired Usage:

Dual USB-C Ports: One for data, the other for independent power input. This separation minimizes electrical noise and enables simultaneous charging and playback.

Headphone Outputs: Single-ended 3.5mm (PO/LO/SPDIF) and balanced 4.4mm (PO/LO) ports accommodate diverse headphone types.

Wireless Usage:

Bluetooth 5.0: SBC, AAC, aptX, aptX HD, LHDC, and LDAC codecs ensure high-resolution wireless transmission.

Bluetooth DAC/Amp Mode: The M23 can act as a receiver, streaming audio from external sources and amplifying it for wired headphones.

AirPlay Support: Seamless integration with Apple devices expands its wireless capabilities.

Performance and Power Output

FiiO equipped the M23 with an AK4191EQ+AK4499EX DAC configuration, renowned for its accurate, low-distortion signal processing. The player’s output power is tailored to accommodate a wide range of headphones:

• Balanced 4.4mm High Gain: 475mW+475mW @ 32Ω
• Single-Ended 3.5mm High Gain: 125mW+125mW @ 32Ω
• Over-Ear Headphone Mode (Balanced): Up to 1000mW per channel

With an SNR of 125dB and a THD+N rating of 0.00038%, the M23 ensures pristine audio reproduction across all volume levels. The low noise floor (<1.9μV PO, <3.1μV BAL) eliminates unwanted hiss, even with sensitive in-ear monitors (IEMs).

Battery Performance

The M23 houses a 5500mAh battery, offering:

• 10.5 hours (Single-Ended Output)
• 9 hours (Balanced Output)

The independent power input port allows bypassing the internal battery during stationary use, preserving battery longevity and maintaining consistent power delivery.

Listening Impressions

The M23 delivers a neutral yet engaging sonic profile, ensuring minimal coloration while enhancing detail retrieval and spatial imaging. The DAP drives both low-impedance IEMs and power-hungry planar magnetic headphones with authority.

Test Pairings

Audio-Technica ATH-R70xa: Renowned for studio precision, the M23 revealed subtle textural nuances and transient details, enhancing the headphone’s reference tuning.

HIFIMAN HE1000: The M23 exhibited remarkable synergy with this planar magnetic flagship, emphasizing dynamic range and providing ample headroom for complex musical passages.

Storage and Media Handling

With 64GB of onboard storage (approximately 46GB available), the M23 supports microSD cards for expanded capacity. Users with extensive high-resolution libraries may experience initial indexing delays; however, performance stabilizes once files are integrated.

Final Verdict

The FiiO M23 SS is a formidable DAP that rivals more expensive competitors while maintaining an accessible price point. Its premium build, versatile connectivity, and powerful audio performance make it an ideal companion for both casual and critical listeners. Whether streaming wirelessly or leveraging its high-powered balanced output, the M23 excels as a comprehensive portable audio solution.

Retailing at $899.99, the FiiO M23 stands as a testament to the brand’s commitment to innovation and quality. Audiophiles seeking a robust DAP with cutting-edge features will find the M23 an indispensable addition to their collection.

The FiiO M23 SS is available today at Audio46.