8
User's Guide
ADI-2 FS © RME
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6.6 Digital Inputs
The ADI-2 FS has a coaxial and an optical digital input.
The button DIG IN selects the active input.
The digital input format is detected automatically. Be it AES, SPDIF or ADAT, further settings at
the ADI-2 FS are not required. In case of ADAT optical only channels 1 and 2 are processed,
channels 3 to 8 are ignored.
To receive signals in AES/EBU format, an
adapter cable is required. Pins 2 and 3 of a
female XLR plug are connected individually to
the two pins of a phono plug. The cable shield-
ing is only connected to pin 1 of the XLR - not
to the phono plug.
The ground-free design with transformer in the coaxial input offers full compatibility to AES/EBU
along with perfect hum rejection.
The ADAT optical input of the ADI-2 FS is fully compatible with all ADAT optical outputs. RME's
unsurpassed Bitclock PLL prevents clicks and drop outs even in extreme varipitch operation,
and guarantees a fast and low jitter lock to the digital input signal. A usual TOSLINK cable is
sufficient for connection.
SPDIF Double/Quad Speed
Both the coaxial and optical input support all sample rates between 32 and 192 kHz directly.
They operate in the so called Single Wire mode.
ADAT Double/Quad Speed
At sample rates above 48 kHz (Double/Quad Speed) ADAT uses
Sample Multiplexing
(S/MUX)
to be able to operate at up to 192 kHz. The data of the channels 1 and 2 will be transmitted
using channels 1/2 and 3/4 (S/MUX), or channels 1 to 8 (S/MUX4). The ADI-2 FS can receive
and recombine data into 2 channels from all S/MUX compatible devices at up to 192 kHz, natu-
rally including all RME devices with ADAT I/Os.
Emphasis
The ADI-2 FS DA-converter supports Emphasis. This control information, only found in
SPDIF/AES signals, causes the converter to reduce treble. (Note: this technology was used in
the early days of digital audio, and is no longer used since years).
The button ANALOG INPUT - LEVEL offer s a fourth state (DIG). In this mode the ADI-2 FS
operates as Insert DA-converter. The level meter show the audio level of the digital input
signal, which is passed-through internally to the digital outputs.
