@nickpish As you mentioned, it's nearly impossible to come to a universally accepted definition of descriptors, including 'brightness'. To me VM540ML sounds more detailed, with more information extracted especially in the high registers, and most importantly without distortion.
As I mentioned in one of my previous post, I'm also skeptical of some of the descriptors where lack of detail, and a darker, dead-er sound is described as 'musical'. To me there is nothing 'musical' about lack of detail. In the same vain, there is nothing excessively 'bright' about the increased detail in the high registers, which I experienced with VM540ML. But then, that argument gets us back to atmasphere's point about whether you have access to master tape, and really know how something was meant to sound in the studio. And that's where I jump off the audiophile ship :)
As I mentioned in one of my previous post, I'm also skeptical of some of the descriptors where lack of detail, and a darker, dead-er sound is described as 'musical'. To me there is nothing 'musical' about lack of detail. In the same vain, there is nothing excessively 'bright' about the increased detail in the high registers, which I experienced with VM540ML. But then, that argument gets us back to atmasphere's point about whether you have access to master tape, and really know how something was meant to sound in the studio. And that's where I jump off the audiophile ship :)