Take for example the Altec A7 Voice of the Theatre loudspeakers, which you can get a beautifully restored pair for around $3500 USD from Gary Fischer, and then have Pete Rigglebuild a pair of his inexpensive Hiraga-style crossovers for them (around $1000 USD if I remember correctly).
The combination will crush any of the current "high-end" speakers I've heard anywhere near the price, or double the price for that matter, in terms of musicality and the sheer fun factor of their live-like presence, not to mention the personal satisfaction of owning a classic pair of loudspeakers.
As for the Advents versus the top-of-the-line speakers, we can only say that you may prefer them to a pair of KLH Nines or Altec A-7s, or you may not. By all the accepted standard of evaluation (excepting sensitivity, where the Altecs excel), the Advents are as accurate reproducers of sound as any top-line system we have heard. But we must face the fact that accuracy is no guarantee of personal satisfaction with a loudspeaker, and that many people value transparency above lack of coloration and find that a closer or more distant-sounding speaker conveys a more convincing illusion of realism than one that is completely neutral. We feel, though, that listeners who have no particular preference for a certain aspect of or kind of reproduced sound will be as happy with the Advents as with anything costing up to five times as much. Maybe even more so.
Read more at https://www.stereophile.com/standloudspeakers/171advent/index.html#5ryRw4o7edyJ5QJx.99