User's Manual

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User’s Guide ADI-2 Pro FS - v 2.5
15. Top Screens
The ADI-2 Pro has four different meter screens: a global level meter that shows all signal levels
of all I/Os simultaneously, an Analyzer showing the audio signal content on the analog inputs
and both analog outputs 1/2 and 3/4, a state overview showing the digital states of AES, SPDIF
and USB, and a dark Volume screen with comprehensive information.
Pushing the small encoder 1 or 2 while any meter screen is active cycles through all meter
screens. To quickly call them up simply press any of the 4 buttons one or two times.
15.1 Global Level Meter
Shows the signal present at all inputs and outputs. The
upper labels refer to inputs Analog, AES and SPDIF, then
outputs Analog 1/2, Analog 3/4, AES and SPDIF.
At sample rates above 192 kHz AES and SPDIF are
grayed out as they are no longer functional.
These are peak level meters with peak hold function,
bandwidth limited to 40 kHz at higher sample rates.
15.2 Analyzer
The Analyzer is one of the main features of the ADI-2 Pro. Thanks to the high-resolution IPS
panel even smallest details are clear to see. Music content analysis is possible even when
viewed from a greater distance.
The Analyzer is based on RME’s famous Spectral Analyzer in DIGICheck. It uses 29 biquad
bandpass filters for high separation between the bands, providing outstanding musical visuali-
zation. Using carefully selected attack and release times the display is responsive, but still easy
to read. On top it uses RME’s own Max LR technique to prevent 6 dB higher level display for
monaural signals, and zero display with out–of-phase signals.
The Analyzer operates at any sample rate, and even with
DSD. There are no parameters to change, and the shown
frequency range is always the human audible range, 20 up
to 20 kHz.
To be able to also show DC content the lowest band is not
a band-pass filter, but a low pass, catching the whole
range from 0 Hz up to 30 Hz. With some unusual signals it
therefore can happen that the level shown will be a bit
higher than expected.
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 Pro 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.