Groovemaster II tonearm

I’ll bump the thread by adding a few objective details:

The current arm is the Groovemaster III

A mk2 arm can be upgraded to the new counterweight assembly ( and arm lift ) ~ $200

The effective mass of 22g is calculated using ( iirc ) 14g headshell. Or maybe it was 15g. At any rate lighter or heavier headshells can shift the effective mass value...

disclosure- I am a dealer for AudioCreative.

I've asked variations of this question over the years and never got a really straight answer. From what I could discern, it has a powerful, controlled sound but somewhat dark and rolled off top end. I remember when publication's did product comparisons but these single product reviews where everything is wonderful fail to enlighten. 

How can a tone arm make a dark top end?