I stumbled across this thread a few days ago, did a bunch of internet reading guided by AI and thought what the heck, bought the $55 Douk Audio wood box version vs the $$$ audiophile unit. It arrived today, plugged it in, 5 feet high just slightly left behind the speakers. And…when I switch on/off in quick comparison “I don’t think that I think I can tell a difference.” Nothing really in a quick A/B comparison.
HOWEVER, for some reason I do like the music with it on vs off. My system is not super expensive, but I’ve got speaker placement dialed in, big tube amp driving Klipschorns with superb imaging and soundstage. Damn, my rig sure sounds good tonight! Rich, lush detail, sparkling highs, superb midrange vocals, instrument separation and location but in a coherent way. Live recordings with audience clapping sounds like I’m in the middle of them.
Snake oil, placebo effect, science, or whatever…I definitely like it on vs off!