the ADDC measure: measure hardly detectable audio signals (and others)
ADDC means Aligned Digital Degraded Channel, that is a model aimed at completely ignoring the physics of the chain being investigated, only focusing on its input and its output, without making any assumptions on what there is in the middle.
Mainly the ADDC measure is able among other things, to detect the output inaccuracy of a given system with the greatest precision. This allows to well give evidence to phenomenon and effects generally considered hardly detectable and measurable.
It is worth pointing out that, since the first high fidelity audio equipments were developed, there have been endless debates about the possible key measure to identify the best audio systems and what makes pleasant or unpleasant listening to them.
But in spite of any attempt of working out an answer, high fidelity equipments still continue to play jokes on us, for example each time we change or invert a signal cable or twist some of them, or rotate a power plug or even move something: we clearly perceive the sound has changed but it is really hard to say why.
May we try in a different way?