I have to say, early impressions of the Silver Poison are great, a hugely cliched term when it comes to Sennheisers, however I swear that listening to Frank's cable, compared to the stock cable. that a veil has been lifted across the whole tone, especially - to me, being very mid-centric, in the mids where they sound more alive - although the very first clear difference I heard was more treble definition / bite / clarity...
This is with only a few hours on the clock, so the real test / opinions will come in a couple of weeks time - However, I cannot imagine my impressions will degrade between now and then,
I deliberately haven't mentioned soundstage at this time, as I am still pretty darned new to the HD800s as it is, so will need to A/B when I'm fully accustomed to them to hear if I can hear a difference in soundstage as well as tonal balance / power....
I guess, in the case of the HD800, that it must definitely be considered that Sennheiser charge the same, if not slightly more money for a replacement stock cable than what Frank charges for the Silver Poison - with that in mind, and knowing that most of us here are tweakers - this cable to me is a no-brainer...
It is funny that when I bought the WireWorld Ultraviolet I was scorning spending £50 on a USB cable, and now here I am with a custom headphone cable - in both instances differences were noted, for the better - so - a happy camper all around
[Edit] Frank - I wonder why I was up half the night, lol - might be something to do with having a new cable to play with lol - Thanks again for your stellar customer service!