I'm a little skeptical about tweaks, but I get great results and can enthusiastically recommend the following: 1) wrap any remote control devices in black Pashmina (cream, acqua and turquoise will NOT work for some reason), and while keeping them bundled, remove the parcel from the line of sight of your tweeters 2) using any HP calculator with RPN or reverse polish notation, affix it to the center of the top of your power amp using a roughly 50/50 mixture of Blue Tack and Play Doh. I have had especially good results with an old HP 12C. Most important, although not specifically a "tweak", ALL food past its sell by date MUST be removed from the house. Although trickier to discern in the 200-250 HZ region, this combination will dramatically improve most of 10-30khz spectrum and give spine tingling, holographic imaging comparable to systems worth 5-10 times the price.
Snake oil and tweaks that work!
This is in no way intended to bring out argument but discussion of tweaks people have tried and have found success with. I know there are at least 50% of you out there that think everything in audio is snake oil, and you are initialed to those opinions. Please don't make this your battle field! If you want to start an opposing thread calling us nuts and getting in arguments please do, it might be fun to have both going. I want this one to be an informational for people who want to try things. I for one have tried a lot of the recommendations in Stereophile each month, most don't work for me, but I have found a few things that do work. #1 tweak: Speaker location. Even a 1/16" can make all the difference. I try to play with this about every six months. A dedicated circuit from the panel with 10ga. wire had a very noticeable improvement. Cables and wires matter, some have been good for my system, some real bad. We have plenty of threads covering this so lets no go there. The "Bedini Ultra Clarifier" works amazingly well for me, I know it's crazy but it works! The Cardas caps I got for X-mas really worked, they produced a more quite background, go figure. Black Diamond Racing "the Puck and the Shelf " have been great improvements, all the different cones I've tried change the sound, I haven't found one I would recommend. The Audio Prism Quiteline filters work great, but power conditioners and RFI/EMI ferrets did nothing. The last thing that has helped me is furniture location, I find if I move something only an inch it can help or hurt. I look forward to hearing others experiences.