I actually have tried both the standard and the Reference Signal Purifiers in my home system and will honestly say that they do make a substantial difference ( IMPROVEMENT) in the overall sound from the speakers in the room. They go onto the positive leg of the speaker cables only and I have zero idea of why/how they work, but I can tell you that they absolutely do. For the skeptics - as usual, since you haven't tried them, it becomes easy to throw stones.
