
APOGEE ELECTRONICS
6
ROSETTA 800 – User’s Guide
4) LOCK - These LEDs indicate the Lock status of the Rosetta 800’s dual stage
clock. Two levels of lock precision are displayed, Wide and Narrow.
5) SOURCE TO DIGITAL OUTS – This parameter configures the first of two
available signal paths by selecting the input source(s) routed to ALL digital
outputs. A total of eight channels may be routed, either entirely from one source
or from one digital source and the Analog source. To select a digital source and
the Analog source simultaneously, toggle through the entire set of possible values
until both desired SOURCE TO DIGITAL OUTS values are lit. Assignment of each
of the 8 channels to a digital or analog source is accomplished (by pairs) with the
Advanced settings noted below:
Navigating the Front Panel - continued
9) The clock circuitry of a
typical D-to-A converter must
be designed as a compromise
between the ability to attenuate input
signal jitter and the ability to accept any
bitstream, regardless of it’s stability. The
more the clock is allowed to track timing
variations of the input, the more jitter
remains in the clock at the conversion
stage, with the degradation of conversion
quality as a result. The ROSETTA
800’s Dual Stage Clock overcomes
this compromise by employing one
clock stage to accept the bitstream
and store bits in a buffer, and a second
stage to clock bits out of the buffer to
the conversion stage. The first stage is
optimized to track timing variations of the
input, while the second stage is optimized
to attenuate jitter and ensure that
conversion takes place with the lowest
jitter clock possible.
10) When the Rosetta 800 is
running at the 176.4 – 192
kHz sample rate range, neither
ADAT nor ADAT + S/MUX may be
selected.
FIGURE 1
4
5
10
9
11 12
SOURCE TO DIGITAL OUTS Advanced settings:
When two sources have been selected, the following Advanced settings
become available:
• To display current routing:
1) Press and hold the SOURCE TO DIGITAL OUTS button to
display the current configuration of analog and digital sources as
indicated by the DIGITAL OUT LEDs. If the DIGITAL OUT LED is
on, the source for the corresponding channel pair is the Analog
input; if the DIGITAL OUT LED is off, the source is the selected
digital input. For example, in FIGURE 1, channels 1-2 and 7-8 are
set to the Analog source, while channels 3-4 and 5-6 are set to the
ADAT source.
• To modify routing:
1) While pressing the SOURCE TO DIGITAL OUTS button, press the
SOFT LIMIT button to select the pair of channels to be modified;
the selected pair is indicated by the flashing A/D OVER LEDs.
2) While pressing the SOURCE TO DIGITAL OUTS button, press the
OUTPUT RESOLUTION button to toggle the selected pair between
ANALOG and the selected digital source.