Design Notes from the AMR/iFi Research & Development department
The Pro iDSD is an all-out assault on the state-of-the-art and its ground breaking digital engine will be used across
the next generation of iFi products.
1) DAC section
The Pro iDSD uses a quad 'core' of iFi audio's bit-perfect DSD & DXD DAC by Burr-Brown in a custom 'interleaved'
con guration. A total of eight pairs (four for each channel) of differential signals are used and mixed.
While the Pro iDSD does include an FPGA for digital lter duties, the FPGAs themselves do not perform d/a
conversion. There are always external d/a sections, with a limited number of elements. In the Pro iDSD we use four
interleaved 64-element converters, to give a total of 256 element DAC per channel, manufactured to the highest
level of precision. Discrete DACs added can neither offer those elements' numbers nor the accuracy required.
All signals to the DACs are re-clocked with the low-jitter Global Master Timing® derived master clock from the AMR
DP-777.
2) Digital Processing
Bitperfect or Upsampled
All digital processing is bit-perfect, without employing ASRC or up conversion unless digital filters embedded the Crysopeia
FPGA remastering engine are explicitly selected. Divergent digital filters (including bit-perfect mode without digital
filtering) are selectable and operate in synchronous mode.
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