While I honestly doubt you could find 40K speakers for 4K, I would say that speaker design hasn't advanced much (if at all) during the last 10 years, and I would remind you that something like a Siemens Bionor (old cinema speakers from the first half of the 20th century) are still considered by many to be state of the art, with some even claiming they're their favorite speaker system. The laws of physics haven't changed. 10 years is nothing regarding speakers. Now if we were talking about DACs or class D amps, it would be a different story.
Buy a pair of ten year old $40,000 speakers for $4,000 or new ones at that price point?
Hi. There are bargains to be had on really high-end components that are more than a few years old. DACs change too much and we need the newer technology. How about speakers? I know it can depend on the specific model but in general is a 10 year old speaker system that was $40,000 in 2009 and now sells for $4,000 a better value than a new system that sells for $4,000 in 2019? How much has speaker and crossover technology evolved in the past decade or so? (I posted a similar questions about amps in that forum). Thanks for all the input and wisdom.