ADC1 Instruction Manual Page 8
Digital Outputs The ADC1 has four digital audio outputs:
three Main Outputs and one Aux Output.
Main Outputs
• XLR connector, balanced, AES/EBU
professional format, 24-bits
• BNC connector, un-balanced, AES/EBU
professional format, 24-bits, compatible
with most SPDIF inputs
• Optical TOSLINK connector, multi-format
(AES professional, ADAT, ADAT S/MUX II
& IV), 24-bits
Aux Output
• BNC connector, AES Professional format,
16 or 24-bits
All of the outputs are controlled by the front-
panel Mode Switch. The status of these
outputs is shown in the Mode Display
adjacent to the Mode Switch.
Three of the outputs are Main Outputs and
always operate at 24-bits. The Main Outputs
may be synchronized to an external clock
reference or may be controlled by the internal
clock. The Optical Output has two modes of
operation; AES/EBU and ADAT. The ADAT
mode supports ADAT (44.1 and 48 kHz),
ADAT S/MUX2 (88.2 and 96 kHz), and ADAT
S/MUX4 (176.4 and 192 kHz).
The Aux Output can operate asynchronously
at 44.1 or 48 kHz with a TPDF-dithered 16-bit
word length. The Aux Output is provided as a
convenience for making safety backups or
demo recordings to low-resolution 16-bit
recorders (i.e. CDR or DAT). If this low-
resolution function is not needed, the Aux
Output can be set to mirror the high-
resolution Main Outputs.
AES/EBU XLR Output This output uses a gold-pin Neutrik™ male
XLR connector. The output is balanced and
has an output impedance of 110 Ohms. This
output is DC-isolated, transformer-coupled,
current-limited, and diode-protected. It is
designed to drive standard 4 Vpp AES signals
into a 110 Ohm load. Use 110 Ohm digital
cable when connecting this output to other
devices. The use of analog audio cables may
cause data transmission errors.
• Data Format = AES/EBU professional
format
• Word Length = 24 bits
• Sample Rate = 44.1, 48, 88.2, 96, 176.4,
or 192 kHz
• Clock Source = Internal or external
Optical Output The Optical Output has four modes of
operation; AES/EBU, ADAT, ADAT S/MUX2,
and ADAT S/MUX4. The ADAT LED on the
front panel is illuminated whenever any of the
ADAT Modes are active. S/MUX2 and S/MUX4
are automatically enabled if required to
support the selected sample rate. S/MUX2 is
active at 88.2 or 96 kHz, S/MUX4 is active at
176.4 or 192 kHz.
The Optical Output uses what is often called a
TOSLINK, Type FO5, or 5 mm optical
connector. The ADC1 uses a special high-
bandwidth version that supports AES/EBU
digital audio at sample rates up to 192 kHz.
Please note that many optical inputs cannot
support AES/EBU or SPDIF digital audio at
sample rates above 48 kHz, others are limited
to 96 kHz. A few products (such as the
Benchmark DAC1) support 192 kHz optical
inputs. Please note that high-bandwidth
optical transmitters and receivers are not
required for ADAT, ADAT S/MUX2, or even
ADAT S/MUX4.
AES/EBU Optical Output Mode
• Data Format = AES/EBU professional
format
• Word Length = 24 bits
• Sample Rate = 44.1, 48, 88.2, 96, 176.4,
or 192 kHz
• Clock Source = Internal or external