Instruction manual

DAC1 HDR Instruction Manual Rev I Page 26
Meticulous Engineering Eliminates
Pops and Clicks
A common problem with streaming audio via
USB is the presence of pops and clicks. Audio
requires constant un-interrupted data flow.
Any gaps in the audio data will cause clicks
and pops if buffers are not working properly.
The Benchmark AdvancedUSB Audio™
solution was engineered to establish and
maintain a properly buffered un-interrupted
flow of high resolution audio data.
Plug it in and Start Listening…
Immediately
Benchmark's Advanced USB Audio
technology is truly 'Plug and Play'. When
connecting to a USB port on a computer
running Windows or Mac OSX, the computer
will automatically and instantaneously
recognize the presence of the Benchmark USB
device. Any audio played from the computer
will then be routed to the Benchmark USB
device immediately. There is no software to
install or configure.
One USB Audio Solution for All
Your Computer Audio Needs
Most devices with custom drivers only
connect to one application at a time. This is
especially true with devices using ASIO
drivers with Windows operating systems. The
device will 'lock' to a specific audio
application, leaving all other applications
unable to access the device. Benchmark's
USB technology allows as many applications
to access the device as needed. This
convenience allows the user to switch
between a music player and a video player or
web-streaming player without needing to
reconfigure any software or hardware.
Advantages of 24-bit Playback of
16-bit Sources
Why do I need a 24-bit USB audio device to
play 16-bit 44.1 kHz music files?
The reason is that digital volume controls and
digital mixers increase the word-length of the
audio. The longer word-length is a result of
multiplication and addition. These arithmetic
operations produce long word-lengths that
must be squeezed back into a shorter word
length. Word-length reduction adds noise
and/or distortion to the audio. The amount
that is added is determined by the output
word length.
The noise and/or distortion added by word-
length reduction decreases by 6 dB for every
additional bit that can be retained. Reduction
to 16-bits adds 48 dB more noise than
reduction to 24-bits. In general, 16-bit word-
length reduction is very audible; while 24-bit
word-length reduction produces noise levels
that are well below audibility.
Our tests show that 24-bit output devices
deliver a dramatic improvement in sound
quality when playing 16-bit material. Native
USB output devices have had a reputation for
poor sound quality. This is primarily due to
the 16-bit word-length reduction.
Benchmark’s AdvancedUSB Audio™
technology breaks the 16-bit barrier and
delivers pristine digital audio to the D/A
converter. Benchmark’s UltraLock™ system
insures that the D/A converters deliver this
audio to the analog outputs without adding
jitter-induced distortion artifacts.
Recommended Settings for
Computer Playback
Benchmark has done extensive testing on
various operating systems and media players.
These tests determine the optimal settings for
high-quality playback.
Although the results of the tests are highly
definitive, they are quickly out-dated due to
the nature of software updates. For the latest
information available, please visit our
complimentary information resource center
online:
http://www.BenchmarkMedia.com/wiki