AVX have "audio grade" capacitors, and they watch my videos. I'm going ask them to prove their marketing claims, and in what way their "audio grade" are manufactured differently from their regular capacitors of the exact same spec. And how they actually quantify "deeper bass" and all those wank words. Let's see if I get a response
Meanwhile you can check AVX audio tantalum benchmark paper: https://www.interstatemarketing.com/Papers/TechArticles/Tant-Niobium/tantbench.pdf
You know, a benchmark "paper" (it is not peer reviewed nor published) where the authors are two reps of the capacitor manufacturer, a rep of a company selling equipment using those caps and two guys from a Czech uni that got likely roped in to give this some kind of scientific veneer (Zajaček was a PhD student and J. Šikula is likely professor Josef Šikula who was his thesis advisor - and most likely had nothing to do with this paper. It is routine to put the name of the advisor on publications by the student as a courtesy) is totally a valid and trustworthy source of information.
And "published" by a dealer of AVX (seriously, I thought "interstatemarketing.com" was a spam domain - the name doesn't get much more spammy than this).
BTW, there is absolutely nothing about any special "audio tantalums" in that paper. They measure things like THD, sensitivity to piezoelectric effect and impact of ESR of different capacitor technologies (regular consumer tantalum, low ESR tantalum and 2 polymer tantalums in parallel, normal and low ESR niobium oxidide type, normal electrolytic and X5R MLCC) that AVX manufactures when used as a coupling capacitor for a Wolfson audio codec (supplied on an eval board - that's likely why there is the Wolfson rep as a coauthor).
I have no means to check the measurements but just looking at how this is written is making me laugh (yeah, I did review a few research papers before). The best are the final results - they recommend the tantalum caps over aluminium elcos, even though the elcos were at least as good as the tantalums in their test with this copout:
"Aluminium capacitors performed well in the tests, however a special care should be paid to their limited reliability, capacitance drop with time and lead-free process compliance. This is beyond scope of this paper. For Reference see 7."
Where reference [7] is a marketing paper by AVX written by the same AVX rep that is the coauthor of this "study" (3 out of total 8 references are self-citations by this guy) about how their niobium oxide "Oxicaps" outperform aluminium elcos. Which actually this study doesn't show - the "Oxicaps" performed the same or worse than both the tantalums and the elcos.
You can guess why they had to write that despite the results, given who has supplied the capacitors and paid for the study
I am really sorry for the PhD student that they had convinced to do the measurements and to put his name on this "paper".
(We are talking small signal audio coupling caps here, not highly loaded power supply switching filter caps or coupling caps passing many watts of power where an aluminium elco would be particularly stressed).