Thats a stunningly good suggestion that can result in gob as well as face smacking results of epic mind blowing and life altering proportions. My favorite statement is something is so good it has altered all known laws of physics. When I see any of these comments I take them with a grain of salt. For me, when I read that the ----- whatever it is product was great but the sound really opened up when I switched power cords or different interconnects- the review ends for me and the magazine goes in the trash.
Alas the 621 isn't that good- but running 2 channel PCM from my K player when playing back bit accurate ripped CDs, it was quite a pleasant surprise for me in my system. Noticeably better than straight coax from the K PLayer to the 861. Its exactly as the others have said- the cleaned up sound allowed me to hear things I was missing before. Its kind of like fixing the sharpness on a friend's monitor when they had it pegged at 100% with the intent of seeing more, but the reality was they were seeing less because the ringing and false contouring the control was introducing was obscuring real picture detail. When you bring it back down, you can actually see more. I think the best way to say it is, after hearing this, I am ruined for other setups. IF the 861V4 will get it, I would wait. But if you decide you want the high res blu ray (and hddvd?) formats, then this filter is a great bonus in the 621. Whats your audio transport? Streaming? There must be a way to get that signal on HDMI.
My whole setup is in my signature. I could test playing CD's on the PS3 initially. I'd have to add another component to convert SPDIF to HDMI. And I'd have to rearrange the rack to fit the HD621. And I'm not sure how good the cheap SPDIF to HDMI adapters are and if it can handle the occasional 24/96 native material from the Transporter. I don't mind doing all that if it's the only way, but it would be frustrating if the firmware came out, because that would be a much better solution (sound wise, money wise, system tidiness wise, time wise). Lately we've been watching movies once a month, not worth it for movies. But music is every day.