No these tweaks really work!
Mike, thought you're gettin' out of the audio business?
I've been playing tweaks a little lately also. You are aware, I've played with my cheap DIY preamp (a Cary vintage kit I did some years ago). Since I put in a 10 uf on the output side, I've been tinkling with it. Coupled with the loss of my oldie Meridian CD player (the best sound I've ever had from a CD player), I just never quite liked the sound. The 10 uf opened up the sound, as it was kind of on the dense side. I just lost much of the tonality I loved.
I've always had some (wood) cones under the units. One day couple weeks ago, I just threw a couple of wood flats underneath (from a woodwork project someone was doing), just pine 2x3 wood I think. Well.... it beat the hell out of those fancy wood cones. With cones, I've always thought the sound was on the thin side (supposedly they improve on focus and soundstaging). The mids and lows were never the way I liked. The NO-COST wood chips somehow gave me back some tonality in the low and mid area.
However, the highs were still short. Then, I just threw a book, one of those with glossy paper, i.e. heavier stock paper (not the newspaper type of paper) under the pre. Well... I like the sound even more. Go figure!
So, all these years, blowing away much $$, I could have saved hundreds, and got better sound with junk and.....