Overview

The FiiO JM21 is a portable high-resolution digital audio player built on a Qualcomm Snapdragon 680 processor in an ultra-thin aluminum body, running two Cirrus Logic CS43198 DAC chips paired with dual SGM8262 op-amps in a fully balanced circuit. It plays through a 3.5mm headphone output or a 4.4mm balanced output, reaching up to 700mW+700mW into 32Ω balanced, and its 4.7-inch HD touchscreen makes browsing and controlling playback straightforward. Bluetooth 5.0 transmits over SBC, AAC, aptX, aptX HD, LHDC, and LDAC, and can also receive audio over SBC, AAC, and LDAC from another source. As a USB DAC it supports up to 384kHz/32bit and native DSD256 for local playback, or 768kHz/32bit and DSD512 over USB. The JM21 comes in a 3GB+32GB configuration with up to 12.5 hours of battery life, or a 4GB+64GB configuration with up to 16 hours, and both support microSD expansion up to 2TB. It measures about 120.7 x 68 x 13mm, weighs about 156g, and comes in Black or Sky Blue.

Simcoe Audio Video Insight

The JM21 packs genuinely capable dual-DAC hardware and a 4.4mm balanced output into a slim, phone-like body — it's an easy player to live with day to day without feeling like a compromise on sound.

• Two CS43198 DACs in a fully balanced circuit
• 4.7-inch HD touchscreen in an ultra-thin body
• Two-way Bluetooth 5.0 with LDAC and aptX HD

Best for the FiiO JM21: use the 4+64G configuration's larger storage if you plan to carry a big lossless library without relying on a microSD card.

More Details

Why It Wins

• Two CS43198 DACs: Paired with dual SGM8262 op-amps in a fully balanced circuit for a clean signal path.
• 4.4mm Balanced Output: Reaches up to 700mW+700mW into 32Ω, well beyond typical slim players.
• 4.7-Inch HD Touchscreen: Makes browsing a large library and controlling playback straightforward.

What Makes It Different

Many slim digital audio players trade away balanced output or a large screen to stay thin. The JM21 keeps both in an ultra-thin aluminum body, and its two-way Bluetooth means it can transmit to wireless headphones or receive audio from another source over LDAC.

Technical Highlights

• Two Storage Configurations: 3GB+32GB or 4GB+64GB, both expandable via microSD up to 2TB.
• Two-Way Bluetooth 5.0: Transmits over SBC, AAC, aptX, aptX HD, LHDC, and LDAC, and receives over SBC, AAC, and LDAC.
• High-Resolution USB Input: Supports up to 768kHz/32bit and DSD512 over USB.

Buyers Guide

Who This Is For

• The Everyday Carry Listener: Wants a slim, phone-like player rather than a thicker flagship body.
• The Balanced-Output User: Wants real balanced power in a compact form factor.
• The Wireless Listener: Wants two-way Bluetooth for both transmitting to headphones and receiving from another source.

Ideal Use Case

• Everyday Portable Listening: Browsing a large library on the touchscreen and listening through the 4.4mm balanced output.
• Wireless Listening: Transmitting over LDAC or aptX HD to wireless headphones.
• Receiving Audio: Using Bluetooth receive mode to play audio from a phone or laptop through the JM21's DACs and amp.

What To Pair It With

• Headphones or IEMs with a 4.4mm Balanced Cable: To make full use of the balanced output.
• A microSD Card: To expand storage up to 2TB beyond the internal capacity.
• LDAC or aptX HD Bluetooth Headphones: For high-resolution wireless listening.

Alternative Options

If you want a bigger screen and Android app support, FiiO's M21 covers similar core playback with a full Android operating system.