Are Shakti Stones effective?


I have never used Shakti Stones and wonder if they really work and, if so, what do they do,  I have used the Shakti Holographs and found them to magically focus the sound and tighten the soundstage. From what I have heard, even from Shakti, is that the stones make a significant difference is some usage and less in other. Has anyone used these and what do they do?
mglik
Depends on were you use it.
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One would have a real set of stones to argue this one!