Tweek Geek and crystals (from their web site)
"My own experimentation began by placing large crystals of quartz, amethyst, tourmaline and other stones on top of cables, components etc. Most had next to no effect, some made me think there was a good improvement, only to determine later that it made the sound to bright and edgy. Not to mention looking like a crazy person to my family and friends.
I also learned that the process of evaluating the effect of crystals is a difficult process. This is why I also think that Crystal based products get a bad rap sometimes. Their effect takes time to develop, sometimes a few days to stabilize. Removing them from the room does not immediately remove their effect either. It appears the room itself needs time to "discharge" once the crystals are removed. Usually an hour or two. Up until I learned this I made too many snap judgements. Removing crystals and listening immediately afterward had me thinking that some made no difference. However, returning to the "un-crystallized" room hours later I would notice their absence. This was the cause of many re-evaluations."
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>>>>>I’m heartened to hear that another tweak manufacturer has been experimenting with crystals. As he intimates, crystals are enigmatic and complicated. My Brilliant Pebbles, introduced at the London HiFi Show in 2003, were the first comprehensive crystal based products for audio applications. Power to the Pebble!
Note to self: why did Tweek Geek discuss crystals just before Sonic Tonic. Is Sonic Tonic crystal based? Is this really just a wannabe copy cat of my Micro Brilliant Pebbles for Interconnect connectors and speaker terminals? The first version of Brilliant Pebbles were, uh, crystals contained in small laboratory glass bottles. Coincidence? Hmmmmm..