Instruction manual

DAC2 DX Instruction Manual Rev A Page 20
The DAC2’s USB AUDIO 1.1 MODE provides driverless operation with Windows XP/Vista/7/8, Mac
OS X, and many Linux operating systems.
USB AUDIO 2.0 MODE
The DAC2’s USB AUDIO 2.0 MODE provides driverless operation with Mac OS X. It is compatible
with Windows XP/Vista/7/8 if the Benchmark driver is installed. It has been tested on Mac OS X
versions 10.6, 10.7, and 10.8.
For the up-to-date information about more recent operating systems and suggestions for
optimization, go to:
http://benchmarkmedia.com/pages/dac2-drivers
D1 and D2 - Optical Digital Inputs
The optical input connector is commonly known as a TOSLINK connector. The TOSLINK optical
connector used on the DAC2 is designed to work well at sample rates up to 96 kHz. Maximum
word length is 24-bits. All sample rates between 28 and 96 kHz are supported. The optical input
will accept professional AES/EBU data formats or consumer S/PDIF data formats. The optical inputs
do not accept ADAT format.
In some cases, TOSLINK connections will operate at sample rates above 96 kHz, but the
connection is usually not reliable.
Many MAC computers have a TOSLINK optical output hidden in the 1/8" headphone output. A
special 1/8" optical connector is required to access this cool feature. Benchmark sells the
appropriate cables.
D3 - AES XLR Digital Input
The AES XLR digital input is transformer isolated. Input impedance is 110 Ohms. Maximum word
length is 24 bits. All sample rates between 28 and 195 kHz are supported.
The AES XLR input is DC isolated, transformer coupled, current limited, and diode protected. The
XLR body and pin 1 are both bonded directly to the chassis to prevent currents in the internal
ground system. This direct bonding also maximizes RF shielding.
TIP: Shielded 110-Ohm digital audio cable is required for stable performance. Do not
use analog XLR cables.
D4 and D5 - Coaxial Digital Inputs
The coaxial inputs use female RCA connectors that are securely mounted directly to the rear panel.
The input impedance is 75 Ohms. Maximum word length is 24-bits. All sample rates between 28
and 195 kHz are supported.