Modern USB audio interfaces are USB audio class 2 compliant.

Asynchronous mode, external clock and galvanic isolation are the things to look for.



The Edel USB to I2S/SPDIF interface is an easy to integrate OEM solution for High End USB audio playback systems, supporting both USB Audio Class 1.0 and 2.0.


  • USB 2.0 Full Speed compliant & USB Audio Class 1.0 or 2.0 supported (user selectable)
  • 2-channel asynchronous endpoint for stereo jitter-free playback
  • On board low jitter oscillators
  • External master clock input
  • Resolution up to 24-bits, sampling rate up to 192kHz (96kHz for USB Audio Class 1.0) I2S and S/PDIF output
  • Full galvanic isolation
  • Based on XMOS XS1-L1 controller/DSP in 128TQFP package and SMSC USB3318 USB PHY.

Amanero OEM Combo384 Module 79

OEM Combo384 Module - USB class 2 to I2S 32bit and DSD output Converter


Supported Sample Rates: 44.1Khz 48Khz 88.2Khz 96Khz 176.4Khz 192Khz 352.8Khz 384Khz Output Format: I2S 32bit and native DSD 2.8224 Mhz - 3.072 Mhz - 5.6448 Mhz - 6.144 Mhz Oscillators: 2 Low Phase Noise TCXO

Dimension 30x69mm

Note DSD output enable line to signal an incoming DSD stream.

The card supports output mode only.

NO Drivers needed for Mac OSX 10.6+ and Linux with UAC2 compliant kernel KS/Wasapi/Direct Sound Drivers for MS OS Xp to Win8 32-64bit included at no fee.


Audiobyte USB to I2S converter

  • 192K asynchronous USB interface
  • bit-transparent streaming
  • Win XP, W7, Vista, MacOS compatible
  • USB powered or external


Clones Audio SHAAR 162

Audiophile PCIe-to-USB audio gateway with ultra low-noise regulators for digital chips, clock and USB power; power input noise filters; and an extreme low-noise master clock module with precision 1ppm TCXO.

Added 2016

exaDevices USD 430.00

exaU2I Multichannel Asynchronous USB to I2S Interface -

Asynchronous operation is achieved by using fast FPGA control core, 256 kB FIFO memory buffer and proprietary ASIO driver.

Galvanic isolation of the I2S output from the FPGA core and the USB ground virtually eliminates jitter and common noise originated by the PC. Isolation is achieved by using Giant Magnetoresistive (GMR) Digital Isolators. The barrier capacitance between the board circuits and the I2S outputs is 17 pF.

The I2S output is powered by the external DAC power supply and it is completely independent from the USB power supplied to the board.

Two precision quartz oscillators allow very accurate clocking with minimum jitter for the 44.1 kHz and 48 kHz sample rate families.

Two voltage regulators with low-pass filters provide low-noise power to the FPGA core and the two precision quartz oscillators. This further minimizes jitter and noise.

Custom designed ASIO driver provides automatic sampling rate switching and bit-perfect data transfer. The exaU2I USB ASIO driver operates in asynchronous mode and it is completely independent from the Windows sound system

WDM / WASAPI support is available by using a third-party native Windows driver - Virtual Audio Cable.

JCat USB Card 397.00


  • ultra low noise design for noise sensitive audio applications
  • ultra low noise linear regulators and high quality filters
  • high precision ultra low phase noise oscillator
  • uDP720201 NEC controller
  • two USB 3.0 connectors supporting Low Speed (1.5 Mbps), Full-Speed (12 Mbps), Hi-Speed (480 Mbps) and Super-Speed (5 Gbps) data rates
  • 5V for USB devices can be supplied from a PC’s power supply via an HDD LP4 connector or from an external power supply via a power jack connector
  • for noise sensitive applications the 5V USB power can be filtered by two onboard high performance filters with PSRR better than 90dB at 10kHz
  • in case external PSU is of very high quality, it is possible to bypass the filters and pass 5V USB voltage from the external PSU directly to the USB connector
  • for self-powered USB devices a 5V power is not required for the card operation


Added 1/2015

QNKTC USB-I2S Module US$ 95

The USB-I2S Module is a implementations of the Audio Widget open source project.

It is a fork of the SDR Widget project.

UAC2 and ASIO driver for Windows are open source.


XMOS XS1-L1 USB Audio 2.0 US$ 149.00

  • USB endpoints use the asynchronous synchronization
  • 500 MIPS, 8 threads, XS1-L1 processor
  • 2 Channel analog input
  • 2 Channel analog output
  • USB 2.0 high speed interface - supports multiple 24 bit, 192kHz channels with extremely low latency (3ms round trip)
  • Plug-and-play with Audio Class 2.0 enabled computers (native Mac OSX support, Thesycon Windows drivers available)
  • Audio Class 1.0 compliant - native Mac OSX and Windows support
  • Asynchronous clocking - complete control of the audio master clock

Basically a USB to I2S converter. Optional support for SPDIF/ADAT/MIDI


DSD: XMOS supports the open DSD standard.

A beta is available.


Group Link USB audio 2.0 (24bit / 192khz) module

The chipset is used by third parties to develop OEM modules.

A massive tread on diyAudio

Rigisystems USBPAL

  • Audio ASIO and WDM Interface for Microsoft Windows XP / Vista / W7 32/64bit
  • PCM audio and DSD audio (8in, 8out)
  • 44.1 - 384KHz (DxD) and 64x (2.8MHz) and 128x DSD (5.6MHz)
  • Low latency kernel driver with integrated mixer
  • Microsoft Windows 7, Vista, XP support
  • Apple OS X support
  • CoreAudio, ASIO 2.1 and WDM support

Luckit WaveIO €99.00

Asynchronous USB-to-I2S interface

  • USB Audio Class 2 compatible
  • Low latency (sub 3µs in the best case)
  • 16 to 24 Bit-transparent reproduction
  • 44.1 to 192 kHz standard sample rates supported
  • Built with XMOS processor running @ 500 MIPS

Driver Support:

  • No drivers needed for MAC OS version 10.6.4 and above
  • No drivers instalation required for Linux with UAC2 compliant kernel
  • ASIO/KS/WASAPI/Direct Sound drivers for Windows XP to 7 (32 and 64 bit)
  • Fully featured Thesycon driver package (without 30 min. periodic beeps)

PCI to USB Cards

SOtM tx-USB US$ 300


A audiophile PCI to USB card with ultra low noise regulator for digital, clock, PLL and USB power circuit and ultra low jitter clock for USB clock.

Compliant with USB 2.0
All ports can handle high-speed (480 Mbps), full-speed (12 Mbps), and low-speed (1.5 Mbps)
32-bit 33 MHz host interface compliant with PCI specification revision 2.2


NEC uPD720200 chip with low jitter TCXO and output transformer.

This output transformer is hand made with multi cores silver cable.