Each of the Echoing Orbs is attuned to a different aspect of its master. The method you used in Ashenvale to destroy the Althalaxx Orb will not be effective on the orb we possess. I know of a ritual that may be able to destabilize the orb and allow us to destroy it, but it requires components with specific magical significance. We already possess some of the required materials, but you'll need to retrieve the rest. Take this, it should help you in your search.