Audient ID4 MKII 2-In/2-Out USB-C Audio Interface

Audient iD4 MKII USB-C Audio Interface

The Audient iD4 MKII is a 2-in/2-out USB-C desktop interface built around one Audient console microphone preamp and one JFET instrument input, so a singer-songwriter can record voice and guitar at the same time through two input paths designed for their jobs. The preamp is the same discrete Class-A design used in Audient’s ASP8024-HE recording console, the converters are 32-bit designs, and monitoring, loopback and a dual headphone output are all handled on the unit itself. Everything runs on USB bus power in an all-metal enclosure.

Key features

• One Audient console mic preamp with 58 dB of gain
• JFET instrument input for guitar, bass and keys
• 32-bit converters, 24-bit recording at up to 96 kHz
• Dual headphone outputs, 6.35 mm and 3.5 mm
• Monitor Mix and Monitor Pan for direct monitoring
• Audio loopback for streaming, podcasts and calls
• ScrollControl encoder for DAW and plug-in control
• USB-C bus powered, true phantom power over USB

The console mic preamp

Audient’s microphone preamp is a fully analogue, discrete design taken from its large-format console, not a scaled-down interface preamp. It provides 58 dB of gain range, an equivalent input noise figure of -129 dB A-weighted, and total harmonic distortion and noise of 0.0017 percent at 0 dBu, which together produce recordings that are clean and true to the source with a touch of analogue warmth. The input accepts microphone and line sources, with a maximum microphone input level of +12 dBu, and 48 V phantom power is delivered properly over USB, so condenser microphones get the power they actually require rather than a reduced supply.

JFET instrument input

The second input is a dedicated JFET DI, the same style of input stage used in valve amplifiers, designed to keep the feel and top end of a guitar or bass intact when recording direct. Its gain range is 40 dB. Recording a DI alongside an amplifier microphone, for later re-amping or amp simulation, is where this input earns its place. Because the microphone and instrument inputs are separate, a vocal and a guitar can be tracked simultaneously, each through the right circuitry.

Conversion and monitoring

The 32-bit converters deliver a DAC dynamic range of 125.5 dB A-weighted on the line outputs and headphone outputs, and 120 dB A-weighted on the analogue to digital side, numbers that keep quiet detail intact and make mix problems easier to hear. Two line outputs feed studio monitors, with a speaker mute button on the panel. Both headphone sockets, one 6.35 mm and one 3.5 mm, can be used at the same time and drive headphones up to 600 ohms, Monitor Mix blends the live inputs with computer playback for latency-free tracking, and Monitor Pan positions the direct signal. The large encoder works as a volume control and, in ScrollControl mode, adjusts DAW and plug-in parameters under the mouse pointer. Built-in loopback mixes microphone and computer audio for streams, podcasts and video calls.

Desktop practicality

The iD4 MKII connects over USB-C with USB 3.0 bus power, needing a port that can supply 0.9 A at 5 V as a minimum, and works with macOS, Windows and iOS. The all-metal enclosure measures 133 x 120 x 40.7 mm and weighs 0.74 kg, staying put on a desk and surviving a bag.

Choose the iD4 MKII if one microphone and one instrument, recorded properly, is your whole requirement. The console preamp, the JFET DI and the conversion quality are the same standard Audient applies in its larger interfaces; the iD4 simply leaves out the extra channels you would not use.