Owner's Manual

13
Design Notes from the AMR/iFi Research & Development department
The Pro iDSD Signature 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 Signature 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 dierential signals are used and mixed.
While the Pro iDSD Signature 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 Signature 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 oer 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 lters embedded in
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.de.