BSS Audio FDS366T OMNIDRIVE User Manual page 13

Features
Some of the features are explained in greater detail here.
• 96kHz Sample rate
The FDS-366T operates the A-D and D-A converters and the Digital
Signal Processing (DSP) at a sample rate of 96kHz. The use of a higher
Nyquist frequency enables the audio bandwidth to extend all the way
up to 40kHz. With this extra frequency response we have also been
able to incorporate more accurate filter sets for a more natural, open
sound.
There is also benefit from the improved filter response shapes when the
nyquist frequency (the maximum frequency of which the DSP can
correctly process the signal), moves up from 24kHz to 48kHz. Low-pass
filters and bell filters then retain their magnitude and phase response
shapes more accurately.
• AES/EBU digital input
The FDS-366T is equipped as standard with a stereo AES/EBU digital
audio input which will accept sample rates of 44.1, 48, 88.2 and 96kHz.
44.1 and 48kHz modes are sample-rate converted and the waveform
interpolated to 88.2 and 96kHz respectively within the FDS-366T so
that all of the filtering is done at the higher rate to get more of the
benefits of the increased sample rate. Using the AES input the
realisable dynamic range is increased to greater than 117dB.
• Phase matching
This feature maintains the inter-band phase relationship true to the
crossover type selected (Bessel, Butterworth, L-R etc), regardless of any
interference from far-end crossover filtering.
In 2-way crossovers, this is not an issue since each band has just one
high-pass or low-pass filter. Three or more bands however, cause at least
one band to have both low-pass and high-pass filters which react with
one another, so disturbing the correct phase relationship at the crossover
point. This can result in poor combining of adjacent crossover bands,
resulting in an irregular frequency response and non-uniform polar
characteristics.
The Phase Matching technique used in the FDS-366T eliminates this
problem by compensating for these phase anomalies. The phase
compensation can be bypassed if not required.
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FDS-366T