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If you said "120dB S/N 600-ohm TPA6120A2-based headphone amp with C-Media CM6631A asynchronous USB, PCM 1792A DAC, mirror-imaged circuitry, Wima FKP2 and Nichicon Finegold caps, precision clock tuning, hot-swappable op-amps, hi/lo gain, dual volume controls for headphone/pre-out, two digital and one analog input, with TI NS-LME49720 and 4562NA op-amps standard but three junctions can be rolled to customize the sound"... then STU is your uncle. Say hola!


Besides roly poly with opamps and dual volume controls, the STU offers two more features unusual in its price class: selectable DC servo and volume-control bypass both set with internal jumpers.

This deck thus envisions an upgrade path of becoming a standalone DAC followed by a separate preamp whilst its dedicated headphone attenuator remains unaffected.

There's even a 'bit perfect' confirmation LED to show proper ASIO driver support. Clearly our Taiwanese engineering team thought hard on how to package various high-endy features into an entry-level model with a non-threatening user interface, hide certain easter eggs inside for the more intrepid users, then give it all a friendly sticker for appeal to the new target audience everyone in upscale hifi bemoans we must foster. With so much hand wringing and lip service on the subject it's lovely to see someone actually do something about it.

For those in this group who even know what to do about/with DSD 64/128, AES/EBU, balanced headphone drive, fully balanced line-level outputs, remote control and a built-in linear rather than external switching power supply, there's the forthcoming Xonar Essence 3. It's built on an AD1955 DAC with CMedia CM6631 USB transceiver and tucks into a slightly taller housing of the same sort. ASUS really are all on about building bridges.

On the Essence 3 my company contact Rajinder 'Raja' Gill in the UK had this: "MSRP remains undetermined as I’m not sure yet whether we'll bring this model into the North American market. The lead engineer told me how he voiced this unit against the W4S offerings and says we’ve bettered them on sound quality especially dynamics."