The Active Snare System is a replacement snare that retro-fits to any 14" snare drum using a single-sided strainer/throw off. Probably inspired by the vintage Rogers Dynasonic system. This innovative alternative to the snappy snare uses an anodized aluminum carrier to pre-tension the wires, allowing the unit to be adjusted with significantly less pressure against the bottom head for more sensitivity, resonance and volume from the drum. I have had these mounted on all my snare drums since the 90's. I don't think these are manufactured any more. Fantastic sensitivity.
I will provide your choice of tapes/strings if you need.