FiiO RETRO BOX Desktop Bluetooth Speaker - Black

The RETRO BOX is a compact desktop Bluetooth speaker styled as a cassette deck, with a drop-down front door that holds a FiiO JM21, M21 or M33 R2R player. Dock the player, pair it over Bluetooth, and its screen fills the front of the speaker with a spinning cassette or VU-meter display while the music plays through the speaker. It also works as an ordinary Bluetooth speaker with any phone or tablet, and as a USB DAC speaker for a desktop or laptop computer. Available in Black and White; this listing is the Black finish.

Acoustic design

Two 40mm full-range drivers fire out of the sides of the cabinet, each paired with its own passive radiator in a separate chamber so the two channels do not interfere with each other. The side-firing arrangement makes room for the docked player and spreads the sound more evenly around a room rather than beaming it forwards. The stereo amplifier delivers 5.3 W per channel and the quoted frequency response is 65 Hz to 20 kHz. A built-in DSP offers four sound presets, HiFi, Retro, Pop and Warm, selected by pressing the volume knob.

Connectivity

Bluetooth 6.0 supports the LDAC codec as well as SBC. In USB DAC mode the single USB-C port on the rear accepts 44.1, 48 and 96 kHz audio at up to 32-bit with driverless UAC 1.0 support. The USB port carries both data and power and the speaker draws charge from whatever it is plugged into, so FiiO recommends a computer rather than a phone or tablet for wired use. A microphone on the top panel allows hands-free calls and voice assistant access when paired with a phone.

Docking FiiO players

The front door is hinged at the bottom and held shut by magnets. A mounting insert for the JM21 and M21 comes pre-installed; remove it to fit the larger M33 R2R. Cut-outs on either side keep the docked player's buttons, headphone outputs and card slot accessible, and a PUSH button on the rear ejects the player. With a compatible FiiO player docked, the speaker's top-panel buttons control playback, the power button switches the player's screen on and off, and a double press of the track buttons cycles through the cassette-style display themes.

Power and controls

Two 18500 lithium-ion cells wired in parallel give around 10.5 hours of playback (FiiO's figure, measured with the SBC codec), and a full charge takes about 2.5 hours from a 5 V 2 A USB supply. The top panel carries a red power button, play/pause, previous and next track buttons and a rotary volume knob. Threaded strap mounts on each side take an M4-screw shoulder strap, sold separately, and anti-vibration foot pads keep the unit steady on a desk. The FiiO Control app adds a custom EQ, Bluetooth codec selection and firmware updates.

In the box

RETRO BOX, USB-A to USB-C cable, JM21/M21 mounting insert, quick start guide, warranty card and instruction card. The music player is not included.