Tech Notes

SPECIAL TECH
OptimaLoop | NEGATIVE FEEDBACK THAT’S PURELY POSITIVE
‘Negative feedback’ is used in amplifier circuits
to compare the output signal with the input
signal and correct errors, in order to control gain
and reduce distortion. For sound quality, this is
positive; but commonly applied, one-size-fits-all
‘global negative feedback’ can highlight different
problems whilst solving others – corruption of
the error signal, phase shifts, group delay and so
on can all have a negative impact on sound
quality.
Recognising that different parts of a circuit
benefit from specifically optimised feedback
loops, iFi has developed a negative feedback
system that is much more accurate than the
usual approach. This incorporates multiple
feedback paths instead of a global loop, each
path optimised for a particular function and
working synergistically with the others to deliver
optimal overall performance. iFi calls this new
configuration OptimaLoop.
PureWave | BALANCED CIRCUIT DESIGN FOR THE PUREST SOUND
Balanced, differential analogue circuit design has
long been championed for its ability to reduce
noise and cross-talk within the signal path by
fully separating the left and right channels. The
iDSD Diablo benefits from further refinement of
balanced, symmetrical dual-mono topologies
with short, direct signal paths. iFi calls this circuit
concept ‘PureWave’, referring to the sonic purity
it achieves thanks to exceptional linearity and
infinitesimally low levels of noise and distortion.