Must speakers have certain volume to sound convincing ?

I guess everyone hears things differently, but one of the greatest impressions a speaker has ever left on me was Stan Getz's sax and Astrud Gilberto's voice on Girl from Ipanema as reproduced by large SoundLab panels.  I'm not sure what Inna considers "sounding like real music", but that sure convinced me.

FWIW, I spend a few hours a day with an acoustic guitar in hand or (less commonly) seated at a piano.  I do have the reference at hand on a daily basis.

Well, Getz's sax and even more Gilberto's voice don't impress me regardless of speakers.
Everyone hears differently or processes what is heard differently? Assuming good hearing, of course.

Hello Roxy54, 
You clearly  appreciate both panel and horn speakers.  Which would you choose to build a system around if you could only have one?
Charles, 

I suspect it has a lot to do with how much damage your ears have sustained. 

I think any speaker has to play loud enough to:
1) sound convincing or somewhat realistic
2) portray dynamics
3) pressurize the room
4) reveal, or at least, plumb the lower regions convincingly
5) reveal ambience
One can always go louder but I find that proper matching (or just serendipity) can negate the need to go really loud and still be convincing.

All the best,
Nonoise