GoomazegoM :
I think that makes sense. So I'd be better off with the 100W speakers at 4-6 ohm than the 125W at 6-8 ohm?
Nope.
The numbers given tells you it's worse at lower ohms 6, than higher, 8.
The 8 ohm spec is better because is telling you LESS DISTORTION, at the entire audio range.
The 6 ohm spec is telling you it's got MORE DISTORTION, not only that, it's only measured at 1 kHz, one point in the entire audio spectrum.
What you like best? when the doctor says you can do THIS ONLY when you are rested, or you can do THIS all the time?
It's all very sad. I grew up with the famed, now defunct Stereo Review, when things were spec as X watt RMS, at 1/3 volume for 1 hour, 20-20 kHz, +/- so many DB THD Y. (they didn't say but it was assumed both stereo channels at the same time). All that told you the spec maintain its constancy throughout the audio spectrum and only varies so much (DB), and able to do this for one whole hour at 1/3 the power, so a real-life, I'm telling you because the box actually did this.
Nowadays, spec with 1 channel? you gotta be kidding me, who ever run with 1 channel EVER, and if you have surround, most likely one would have all speakers active even if you are playing stereo. Why is this bad? as more channel comes on, the total available power lowers, lower by how much, alas THEY DON'T TELL YOU!
Subscribe to youtube's audioholics, they talk about this stuff better than I do am sure.