Re: Do you guys agree ???
According to Gerald Weber higher impedances tend to roll off some highs. Say you're given two 8-ohm speakers - you can wire them in parallel for 4 ohms, or series for 16 ohms. (Further assume your amp has taps for both impedances, so it can match whatever impedance you choose). The 4-ohm setup will sound brighter and livelier, because there is less impedance - more specifically, a smaller inductive component in the total impedance, which is what fights the high frequencies.
Reversing this analysis, I can see why someone would thing the 16-ohm setup sounds better for high-gain amps - it will help round off their inherent fizzy, bright nature.
Buy Weber's latest book, it's a gold mine of info, once you get past the lack of literary style.