> Like anything in the art world, it may be misleading to talk about quality at all.
Here's the reality in the humble opinion of a person who understands some art at a sophisticated level and other art not well at all:
Talking about quality is not at all misleading; the idea that quality is just a matter of arbitrary opinion is just false; it's a nice populist notion that people use to comfort themselves when they don't understand something. I used to do it too: 'It's not me; it's the art that's failed.'
There are very real differences in quality. Just because you can't see them doesn't mean they don't exist. Just because something can't be proven quantitatively doesn't mean it doesn't exist (let's start with love and beauty).
If you take that way out, you are cutting yourself off from some of the great insights and achievements of humankind. Instead of comforting yourself, accept there are things that are difficult, even intimidating, for you to understand - that challenge your self-perception as a genius - and either take the challenge of learning them or be realistic and humble enough to accept your ignorance. Having taken the challenge, it has opened up worlds and wonders to my understanding. FWIW, I find it's hard to force myself to grasp the insights at a desired moment; I just have to be open to them, work at it, and one day the light bulb turns on.
I'm also not talking about all art or all kinds of art; we're discussing high priced auction pieces by recognized names versus the quality of items by relatively unknown artists. The problem is that narrative and name recognition trump the discussion of quality; you can't effectively discuss quality because the stories bias the discussion so heavily. We are also talking about price, which further clouds ideas of quality. Price is not proportional to quality in the art world.
The quality of sound of Stradivari violins has been studied, and it has never been demonstrated in controlled conditions that any experts can discern a qualitative difference in Stradivarius violins. You shouldn't assume there is a qualitative difference and go looking for the source of the difference before you can show that the qualitative difference exists.
https://www.thestrad.com/blind-tested-soloists-unable-to-tel...
Interestingly, the study simultaneously staters that the players couldn't identify the older violins but also generally rated them lower. I'm wondering, was there something different about these violins that they didn't like (indicating an identifiable, if unfavorable, difference), or did they feel the old violins just sorta came up short in a non-descript way?
Playing style and tastes have changed over the years, so that could be a factor.
It doesn't seem outside the realm of possibility to make physical measurements to find out whether these differences are likely to be borne out in audible ways, e.g., by looking for differences in resonances of more than a few dB.
What would surprise me, would be if such studies uncovered no differences, because it would mean that the luthier's art has been refined to an exceptional level, in order to make instruments sound the same.
Now, if it's possible to discern a difference, even without being able to identify the source of the difference, then it becomes a completely different matter, which is, which one sounds better? And that's a subjective matter.
Disclosure: I'm not a violinist, but a double bassist, and in the world of basses, there are profound differences in materials and construction among instruments, so the idea that two fine instruments should sound different is quite plausible.
Like anything in the art world, it may be misleading to talk about quality at all. (I know that was part of your point; and I agree with you). These old violins are historical works of art, and they are collectors items based on name recognition and irreplacability. Quality has very little to do with their extremely high prices.
The narrative that these instruments are unequaled is in part a story that adds mystique and credibility to the super high prices. Blind studies have failed to show that Stradivaris and Guarneris sound better to trained ears.
Possibly the biggest irony here is that Stradivarius was doing as much mass production as was possible at the time; he had a violin factory and the violins were made by apprentices, not by Stradivarius himself. The artisanal violins of today are usually made by the luthier.
> I don't have $10,000+ to spend, and I doubt a high end shop would enjoy me running this experiment on their inventory.
It never hurts to ask. When I shop, I don't tell the staff how much money I have, or whether I intend to buy. Chances are if you're interested and ask to play them, they'll let you. Plus if you find the tone you're looking for, you might change your mind about buying.