Had a chance to try out the 15A less expensive MIT Z Duplex receptacle ($150) and I'm pretty amazed. The receptacle is Hubbell medical grade, but with an attached parallel filter. Three separate filters to be precise, each tuned to a different frequency and all potted in a tiny plastic box which is attached to the back of the Hubbell.
As a Goldmund fan, I've been using MIT products for nearly 15 years now. Parallel filtering does not current limit, so I plug my amps in as well.
- Noise floor dropped significantly.
- Bass became more controlled.
- Soundstage gained a bit of width, depth, and holography.
Consider me very impressed.