Are cables additive or subtractive?

I think it is definitely subtractive.

Whether it is cabling, phono cartridges, CD transports or dacs. The goal is to subtract interference, subtract vibration or subtract jitter.

Our goal is to remove all the added crap to get back to a pure signal.

Unfortunately my experience is that they are contextual: their specific resistance, impedance and capacitance characteristics work well in one setting and are negative in another, This applies equally to digital and analogue connections. And the permutations from shielding, gauges, metallurgy and connectors are mindboggling. The best solution therefore is no cable. Think Uptone USPCB…

That said they are a major component in system synergy and a bl**dy money pit.

My 2 cents:

Cables can’t add more or ‘better’ information than is in the original signal (cd, LP, high rez file, master tape), so cables can only ‘contaminate’ the original signal. 

If we call the original music signal “100%” and you replace a cable that only gives you 70% (of the original 100%) for one that gives you 90%, it will sound 20% better, but it did not become 120%.

Back in the Days of Yore (early 80’s) Audioquest sent an IC comparator to their dealers for customers to try. This was a passive device with two pairs of inputs and one pair of outputs, with a rotary switch on top to select pairs of IC A or pairs of IC B. The comparator was connected between a preamp and an amp by a pair of IC C - which could be the same as either A or B. So totally passive with a single switch in the signal path after the preamp. This allowed instant listening to either IC A or B. Audioquest soon withdrew their comparator because nobody could tell A or B apart. I tried it myself and could hear no difference between two pairs of ICs from different mfgrs.

The Audioquest comparator box was an embarrassment to them because it proved that all ICs sound alike - that ICs neither add nor subtract anything to a music signal! That's why I remain an IC atheist after trying the comparator!