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USB Interface
Many DACs in the marketplace have various limitations when streaming music over a
USB connection. These limitations may include limited support for different operating systems,
poor performance, or an inability to play high resolution files. We have ensured that the µDAC-
HD is proficient in all of these areas without any sacrifices. Derived from the latest
asynchronous XMOS design, the µDAC-HD is certified USB 2.0 High Speed as well as Audio Class
2.0 compliant. A quick driver install is required for PC machines; however, it remains driverless
for Mac (10.6.4 and above) and Linux systems. Audio grade clocks, incredibly low latency and
asynchronous mode of operation help ensure brilliant music reproduction.
DAC
For an absolutely fresh start to the analog signal, we decided to convert the digital
stream with the Sabre DAC once again! This chip is based on the same platform as the award
winning DAC-2. The ESS patented Hyperstream™ and Time Domain Jitter Eliminator technology
guarantees a jitter-free digital signal with any input and the sonic result is remarkable! We have
carefully tweaked the output levels of the Sabre to lower noise and distortion. Having the
option to drive the RCA’s directly from the DAC chip would be too easy, so we take it to another
level. To help boost the presence even further, we found the STP-SE line-stage topology to be a
perfect fit for this assignment.
Headphone Amp
For amplified analog resolution, we opted to implement a discrete class A headphone
amp driver. We set out to create a DAC that headphone enthusiasts can place on their desk
taking up negligible space yet packing the power to drive any pair of headphones. Measuring
down to 0.0008% THD+N (Total Harmonic Distortion) with loads at 32 ohms, driving the typical
300 ohm phones should be no sweat! Because of the purely Class A implementation, the USB
connection cannot be used as the power source as it lacks sufficient current. To take advantage
of the discrete circuitry, you will need to use the supplied 9VDC supply. The HD will activate the
class A headphone stage when both DC power is used and the headphones are plugged in.
When in USB powered mode, you can run headphones with an impedance of 300 ohms or
higher with astonishing performance.
Overview
We have combined cutting edge USB DAC technology and a robust headphone amp in a
chassis that will fit in the palm of your hand! Benefiting from advanced engineering technology,
we have been able to design this compact unit without making any major sacrifices in
performance. The landscape of digital music is constantly growing and evolving and this
product is a perfect example of that! The µDAC-HD will refine your casual music sources such,
as Pandora and MOG, while feeling right at home with high-res files in critical listening sessions.
With no more than a Netbook, the HD, and your favorite pair of headphones, you have a
portable reference Hi-Fi system….Consider that!
