Not knowing the NS1000 I looked them up and found this:
It appears, though, that Yamaha may have a tough job of selling their 1000 speakers to buyers, for everyone knows that metal cones sound metallic, and since the speakers are sold without grille cloth covers—the drivers are visible through wire-mesh covers—there is no concealing the fact that the mid- and upper-range drivers on the 1000 are metal. Thus, most audiophiles who have listened to our review pairs of NS-1000s have claimed to hear the metallic quality of those speakers. Interestingly, though, when some of them heard the same speakers, after having been told that other speakers standing next to them were operating, they no longer heard the metallic sound and were quite enthusiastic about what they heard. Strange, what a prejudice can do...
The full review is at NS1000 review
Still an objectiveist review but obviously written by someone who isn't totally fixed on measurement.