has anyone else tried Lloyd Walkers latest tweak

What works in one system may very well not work in another. Stereo systems benefit from tweeking to eliminate resonances, and correct faults. That's what the joy of this hobby is....enjoy.

I'm generally not one to blow my own horn but I was the first to use crystals in comprehensive ways for audio applications. My crystals debuted at the HI FI Show in London in 2003. As I showed ten years ago Crystals can be applied in many locations, including power cord plugs, RCA jacks of interconnects, near small vacuum tubes, room corners, on top of transformers, on top of speakers, on top of CD players, and many other locations.

Lewm, I have a good feeling you will get to the bottom of this thing. That's exactly what I think we need, more folks that are determined to find out what in the heck is going on with these devilish little crystals. If you find something somewhere out there in cyberspace regarding crystals and their use in audio systems, I mean other than in clocks, please be so kind as to provide a link. You would think NASA, DARPA, IEEE, MIT, AES, ASA - somebody! - would have at least done some sort of preliminary investigation. I would even settle for the Amazing Randi. Lol

Geoff, I sense your sarcasm, but I am immune to it. Another computer search today reveals mainly that Google finds either confirmation from many sources that crystal oscillators are a source of RFI OR it finds references in the Tweakers Asylum and elsewhere in audio fora, many of which are to your past postings, when I search on any combination of words that include "crystal" and "RFI". I see that you previously denied the probability that Cardas Caps block RFI from entering into an audio chassis, and on Tweakers Asylum you wrote this in 2010:

"I therefore propose there must be some other mechanism in crystals, when used individually or in groups - besides piezoelectric effect - responsible for the change in sound -- at least when discussing RFI/EMI absorption. I also propose that - in almost all cases - the actual operation of a crystal or group of crystals in an audio system has nothing whatsoever to do with RFI/EMI absorption - rather acoustic/mechanical energy absorption!"

So, we agree (because it's come to be my view as well) that crystals are unlikely to have a beneficial effect via blocking or absorbing RFI, unless you've changed your tune in the past 3 years.

Forgot to add a response to Stringreen: This is not about whether crystals "work" or not. This is about the simple question of whether a crystal can absorb and eliminate or reduce RFI or EMI, at all, to any extent.