Well what I meant was I think I have lost some of the higher frequency's, so in that case I should raise the rear of the tonearm correct?
Correct. Two very important things to keep in mind. First, and foremost, the closer you get to ideal VTA the more important it is that your adjustments be extremely micro. 1mm is macro. .1mm is moderate. The difference between perfect and close is more like .01mm. So micro adjustments.
The other thing to keep in mind, the raise the arm brighter/lower warmer is a very crude way of looking at it. As you get within that last .1mm there will be almost no difference in tone. Instead you are going for focus and a perfect balance between attack, development, and decay. What you will notice is raising slightly emphasizes attack. You hear the guitar string being plucked, and hear the difference between a finger nail and a pick. Lowering slightly emphasizes development, and you hear the difference between the fundamental note of the string and the resonant body of the guitar. Something like that.