The Benchmark DAC1 USB (USB DAC)
is a reference-quality, two-channel 96 kHz 24-bit digital-to-analog
audio converter featuring Benchmark's Advanced USB Audio™ technology,
UltraLock™ clock system, and HPA2™ headphone amplifier.
Engage the Music with the DAC1 and DAC1
The DAC1 USB is a mastering-quality, two-channel 96 kHz 24-bit
digital-to-analog audio converter. For more then 10 years, engineers and
audiophiles have come to rely on Benchmark for critical digital audio
conversion. They consistently find themselves engaged in the music in a
way that is rarely achieved with digital converters.
Benchmark has achieved unprecedented sonic purity in their converters
through intelligent engineering, eliminating digital distortion
artifacts, and maintaining a pristine analog delivery path. The DAC1 USB
continues this tradition of excellence.
Preserving the Classic DAC1 Heritage
The pristine audio path of the award-winning Classic DAC1 has made it
the 'Benchmark' of standalone D-to-A converters. The DAC1 USB preserves
the exact topology of the audio path of the Classic DAC1, while adding
some of the most frequently requested features.
The DAC1 and DAC1 USB both include Benchmark's jitter-immune UltraLock™
clock system and Benchmark's 0-ohm HPA2™ headphone amplifier. The DAC1
USB features Benchmarks AdvancedUSB technology to ensure
bit-transparent, high-resolution playback directly from your computer.
The DAC1 USB also includes a programmable mute function that
automatically mutes the main outputs upon insertion of a headphone plug.
Other features that are exclusive to the DAC1 USB include a
programmable headphone gain range, an automatic 'Standby' feature, and a
high-current output stage designed to drive even the most difficult
Digital interconnect cables, electro-magnetic interference, and many
other variables introduce jitter into the digital audio. Jitter presents
a major problem to most D-to-A converters. Jitter is a type of clock
error that, if not properly addressed, can cause the D-to-A to misfire.
The result of these misfires is a non-musical, digital distortion.
Many modern (and expensive) converters suffer from severe jitter-induced
distortion. Jitter is NOT a problem for the DAC1 and DAC1 USB, which
achieve jitter immunity by utilizing the proprietary UltraLock™
With the UltraLock™ clock-recovery system, the digital-to-analog
conversion-clock in the DAC1 and DAC1 USB is totally isolated from the
clock of the digital audio input. This clock-recovery topology
outperforms even the most well-designed two-stage PLL designs. Using
state-of-the-art Audio Precision testing equipment, no jitter-induced
artifacts can be detected with the DAC1 or the DAC1 USB. Any signal that
can be decoded by the USB or AES/EBU receivers will be reproduced
without the addition of any measurable jitter artifacts. The bottom line
is this: Benchmark converters will consistently and faithfully deliver
truthful audio with no jitter-induced artifacts, no matter what
variables are present.
AdvancedUSB Audio Technology
The USB interface of the DAC1 USB features Benchmark's unique
AdvancedUSB technology. This USB interface is completely
bit-transparent. In other words, every sample of digital audio is
transferred from the computer to the DAC1 USB without modification. The
DAC1 USB is natively compatible with Windows 7/Vista/XP/2000 and Mac OS
X. As a native device, there are no drivers or other invasive software
required to install or configure. The DAC1 USB is a true plug-and-play
DAC USB, and is designed to begin playback immediately after the unit is
connected to a USB port for the first time.
Unlike previous native USB audio interfaces, Benchmark's AdvancedUSB
Audio technology supports 24-bit audio at sample-rates up to 96 kHz. It
is very important to have a 24-bit USB path, even for 16-bit playback,
because certain computer-related functions can increase 16-bit audio to
24 bits. If a 16-bit USB DAC is used, 8 bits of every digital audio
sample would be truncated. Truncating digital audio causes severe,
non-musical digital distortion. Benchmark's AdvancedUSB interface
ensures a full 24-bit digital audio path to avoid truncation distortion.
HPA2™ Headphone Amplifier
The DAC1 and DAC1 USB feature the HPA2™ - Benchmark's signature
high-current, 0-Ohm headphone amplifier. The HPA2™ is arguably the
ultimate reference headphone amplifier. It will deliver the full rated
performance of the DAC1 and DAC1 USB to the headphones. The HPA2™
maintains less than 0.0003% THD+N under full load. The DAC1 and the DAC1
USB both have two 1/4" headphone jacks on the front panel. The
performance of the HPA2™ remains consistent even when two headphones are
being driven simultaneously.