User's Manual

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User’s Guide ADI-2 DAC v2.2 © RME
As opposed to most other solutions no FFT (Fast Fourier Transform) is used. RME's Spectral
Analyzer performs a true band-pass filter calculation, as in professional hardware devices. The
frequency distance between the filters is scaled matching human hearing. The highly optimized
code allows to run a 30 band analyzer with 60 dB range, sharp filters and 0.5 dB steps accuracy
per band, on the ADI-2 DAC DSP, even at 768 kHz sample rate.
The most important application using a Spectral Analyzer is the visualization of frequencies and
levels found in music or speech. The Analyzer shows levels and frequencies even at the edge
of the human ear's abilities – or that of the used speakers and headphone. The visual display
helps to train ones ears, makes coarse errors visible, and shows what sometimes might stay
unnoticed. For example many speakers won't let you hear frequencies below 30 Hz. Simply
look on the Analyzer to see what's going on in the underground.
15.3 State Overview
The State Overview screen is a typical RME feature. Since 20 years we prefer to give our cus-
tomers more information at hand than just ‘something there’. The Settings dialogs of our audio
interfaces include detailed Input Status analysis to simplify setup and ease trouble-shooting.
Additionally RME provides a free tool with any audio interface, DIGICheck, which analyzes lev-
els, Channel Status and bit stream content, the true hardware sample rate and much more.
When the ADI-2 DAC is connected but no sound can be
heard then RME’s analysis tools come to the rescue. The
State Overview screen is there to track down the problem in
an easy to understand and efficient way. Although it might
look simple (fully intentional!), it includes detailed analysis
that outperforms any other similar device.
Shown are the current states of the digital inputs SPDIF
optical and coaxial, and USB connection with the audio
transmitted. The current Clock source is mentioned in full
length, although this information is found abbreviated in the
status bar at the bottom.
The status bar always shows the current volume setting, the current clock source, and the
current sample rate. In case of Sync problems the sample rate will either fluctuate or be shown
in red – or both. This information is available in nearly all screens, and helps to get a quick
overview of the current state. The State Overview screen now extends this information in great
detail.
The SPDIF inputs are shown as SP op and SP co (optical / coaxial). The SYNC column shows
No Lock, which equals no signal present, as
- -. And lock and sync, according to the current
clock state of the respective input.
In case of USB conn (connected) is shown as soon as a valid USB connection is established.
The column SR shows the hardware measured sample rate for the SPDIF input. It will even
display values that can not be set at the ADI-2 DAC itself, for example 32, 64 and 128 kHz. In
case of USB the sample rate is not measured but set by the external computer or iOS device,
and can be verified here, up to the highest value of 768 kHz.
The State column shows the Channel Status, Consumer (cons) or Professional (pro), for
incoming SPDIF (AES) signals. In case a DoP (DSD over PCM) header is detected DSD is
shown. With USB the state column shows the current channel mode, 2/2, or DSD if a DoP
header is detected.