Overview

The FiiO M21 is FiiO's entry-level flagship digital audio player, built around four CS43198 DAC chips working in a fully balanced amplification layout. A Qualcomm Snapdragon 680 processor runs Android 13 behind a 4.7-inch fully laminated touchscreen, and the player uses a patented dual power supply design that switches between desktop and portable modes depending on how it's connected.

Simcoe Audio Video Insight

Running four DAC chips instead of the usual one or two lets FiiO dedicate a fully separate, fully balanced signal path to each channel from end to end, which is part of why the M21 reaches an SNR rating of 126dB. FiiO also splits the digital and analogue sections into their own shielded partitions inside the chassis, a layout more common on desktop components than portable ones.

• Four CS43198 DAC chips in a fully balanced circuit
• Patented dual power supply design for desktop and portable use
• Separately shielded digital and analogue circuit sections

Best for the FiiO M21: connect it to a home system using its coaxial or line output to use the M21 as a dedicated digital transport and DAC rather than just a portable player.

More Details

Why It Wins

• Four CS43198 DAC Chips: A fully balanced quad-DAC layout, one chip per signal path, keeps distortion and noise low through the whole amplification stage.
• 950mW Balanced Output: The 4.4mm balanced output reaches 950mW+950mW into 32 ohms, enough headroom for most over-ear and planar headphones.
• Dual Power Supply Design: A patented switching circuit moves between desktop and portable power modes automatically, based on how the M21 is connected.

What Makes It Different

Where many players in this range use one or two DAC chips shared across both channels, the M21 gives each channel its own dedicated CS43198 chip through a fully balanced circuit, plus separately shielded digital and analogue sections inside the case. It's a layout borrowed more from desktop DACs than from typical portable players, and it's why FiiO positions the M21 as its entry point into flagship-level performance rather than a mid-range model.

Technical Highlights

• 126dB Signal-to-Noise Ratio: A-weighted SNR of ≥126dB with THD+N below 0.0003% at 1kHz keeps the noise floor well out of the way of the music.
• MQA 8x Full Unfolding: Full hardware MQA decoding and two-way LDAC Bluetooth support for both wired and wireless high-resolution playback.
• 20W PD Fast Charging: The 4000mAh high-voltage battery supports PD 2.0/3.0 PPS charging at up to 20W, on top of 15 hours of single-ended playback.

Buyers Guide

Who This Is For

• The Growing Audiophile: Listeners moving up from an entry-level DAP who want flagship-calibre DAC hardware without stepping up to FiiO's higher-tier players.
• The Android App Listener: Anyone who wants direct access to streaming apps on-device rather than routing audio through a phone.
• The Wired-and-Wireless User: Listeners who move between wired headphones at a desk and Bluetooth headphones or speakers on the go.

Ideal Use Case

• Daily Portable Listening: As a standalone Android-based player with wired or Bluetooth headphones.
• Streaming App Playback: Running Android streaming apps directly on the device rather than through a paired phone.
• Home Desktop Duty: Using the coaxial or line output to feed a separate DAC, amp, or powered speakers.

What To Pair It With

• Balanced Headphones with a 4.4mm Termination: To make full use of the 950mW balanced output.
• Bluetooth Headphones or Speakers with LDAC or aptX HD: For wireless listening without giving up high-resolution codecs.
• A microSD Card up to 2TB: To expand past the onboard 64GB of storage for a large local music library.

Alternative Options

The M21 is FiiO's entry point into its flagship DAP lineup. Listeners who want FiiO's R2R DAC architecture and don't mind a higher price should look at the M33 R2R instead, while anyone who wants to spend less and doesn't need Android or a touchscreen interface may be better served by one of FiiO's smaller portable DAC/amp devices.