The device has is roots in an open source project, as a hardware implementation of the Audio Widget venture. The project was started by an online group who wanted to develop the very best solution for a USB DAC. AB-1.2 is the third (counting from 1.0) Analogue Board from the project. The AB-1.2 lets you play high-resolution audio (up to 24-bits at 192kHz) from Windows, Linux and OSX computers.
The analogue section of the DAC design puts equal focus on three areas with a fundamental influence on audio quality. The AKM4430 DAC chip comes from Asahi Kasai, the clock is made from two precision crystal oscillators from Golledge and the power supply uses low-noise regulators from Analog Devices. The DAC generates its own negative power supply, something that QNKTC say makes the whole design less complex and easier to implement. The asynchronous USB protocol (available in both USB Audio Class 1 and 2) makes the DAC the timing reference which is said to minimize jitter errors and further improves on the sound quality.