Zoom U-24 2-In/4-Out Portable USB Audio Interface

The Zoom U-24 is a compact 2-in/4-out USB audio interface for recording, playback, and performance work with computers and compatible iPhone or iPad devices. It gives musicians, podcasters, mobile creators, and DJs a practical way to connect microphones, instruments, headphones, speakers, and MIDI gear in one portable unit. Its two combo inputs and four playback channels support flexible desktop and mobile audio setups.

Designed for clean capture, the U-24 records and plays back at up to 24-bit/96 kHz. Its low-noise microphone preamps are rated at -119.5 dB EIN, helping it accommodate detailed vocal, acoustic instrument, and line-level recording work. Independent gain controls and level indicators make it easier to set levels before recording.

Both input channels use XLR/TRS combo jacks for connecting microphones, keyboards, mixers, and other sources. Input 1 adds a Hi-Z mode for direct connection of guitars, basses, and other passive-pickup instruments. Switchable +48V phantom power is available for condenser microphones and is supplied to both inputs when enabled.

The U-24 offers multiple monitoring paths for studio, rehearsal, and performance use. Main TRS outputs can feed speakers, while RCA line outputs provide another connection option for compatible mixers or playback systems. A dedicated headphone output, direct monitoring control, and adjustable playback balance help create a workable cue or tracking mix without monitoring delay from the computer.

USB bus power keeps the U-24 simple for computer-based use, while two AA batteries or an external 5V supply support portable operation. MIDI input and output add connectivity for keyboards, controllers, sound modules, and other MIDI hardware. Included Ableton Live Lite software provides a starting point for recording and arranging projects, while the interface can serve as the foundation for a larger computer or mobile production system.

Key Features

• 2-In/4-Out USB Audio: Records two channels while providing four playback channels.
• 24-Bit/96 kHz Operation: Supports detailed high-resolution recording and playback.
• Combo Mic/Line Inputs: Connects XLR microphones and TRS line-level sources.
• Hi-Z Input 1: Connects passive guitars and basses directly.
• Direct Monitoring: Lets you monitor input audio without computer latency.
• MIDI I/O: Connects compatible MIDI controllers, keyboards, and sound modules.

Design & Installation

The U-24 uses a compact, portable chassis measuring 191.8 mm deep by 92.3 mm wide by 42.7 mm high and weighing 285 g. Its layout places two front-facing combo inputs, individual gain controls, multicolor level indicators, headphone monitoring, output controls, and monitoring controls within easy reach. Separate TRS, RCA, headphone, USB, DC power, and 5-pin MIDI connections support organized routing for a range of recording and playback tasks.

For computer use, connect the U-24 directly to a USB 2.0 or USB 3.0 port with the included USB cable and select it as the audio input and output device in your software. Connect microphones by XLR, instruments or line sources by TRS or mono instrument cable, headphones to the stereo phone jack, and speakers to the main TRS outputs. For iPhone or iPad use, an Apple Camera Connection Kit or Lightning-to-USB Camera Adapter is required along with two AA batteries or an external power source, because the interface cannot accept bus power from an iOS device.