- XMOS has announced the industry’s first USB Audio Class 2.0 reference design for high channel count computer audio interfaces, DJ and live sound mixers, musical instruments, and digital effects devices.
The new reference design builds on the XMOS L1 USB Audio 2.0 reference design for low channel count (stereo) applications. It is implemented entirely in software using the dual core XS1-L2 XMOS event driven processor. The design supports high-speed USB Audio 2.0 (480Mbps) and up to 18 input and 18 output audio channels at 24-bit resolution and 192kHz sample rate.
Key factors in the design’s reproduction of high quality audio are the use of asynchronous mode and the generation of a highly accurate local low-jitter clock. The reference design also achieves sub-3 milliseconds roundtrip latency, making it well-suited for live music recording applications.
The reference design’s software-defined workflow enables users to readily adapt and customize the solution to handle specific interfacing requirements, DSP algorithms for audio enhancements, and custom front-of-box peripherals. To reduce development time, a ready-made library of software components is available, including I2S, S/PDIF and many other interfaces.
“This USB Audio 2.0 reference design, implemented on XMOS technology, helps developers in the audio industry combat the growing challenges of shorter development times and tougher cost constraints while still providing a vehicle for them to differentiate themselves from their competitors” said Joerg Bertholdt, VP of Marketing at XMOS.
The reference design takes full advantage of the following features of XMOS processors: XMOS event-driven multi-threaded processor integrates audio DSP capability, flexible I/O interfaces and real-time control processing; USB 2.0 high speed interface supports high audio channel counts with 24-bit resolution at 192kHz sample rate with extremely low latency (3ms round trip); support for MIDI and S/PDIF in/out.
The design is Audio Class 2.0-compliant for plug-and-play operation with Audio Class 2.0 enabled computers and Audio Class 1.0-compliant for backwards compatibility and native Mac OS X and Windows support. Native USB Audio 2 driver support is available in Apple Mac OSX 10.6.4 and higher; a version of the XS1-L2, which includes a bundled Audio Class 2.0 Windows driver for Windows XP, 7 and Vista is available.
Asynchronous clocking enables complete control of the audio master clock resulting in minimized jitter and highest quality digital audio. Standard-compliant Device Firmware Update (DFU) loader support provides for in-field software updates to deployed devices.
Additional features will become available later in the year, including digital audio mixing and ADAT with no hardware upgrade required.
The XMOS USB Audio Class 2.0 reference design will be released at the end of July. The source code of the reference design will be available free of charge under a royalty free license. All hardware schematics and design files are available for download from www.xmos.com