To answer your question, the Axioms will extend lower, playing deeper bass and the midrange and highs will definitely be more clear and accurate. I would guess the difference for music would be quite noticable.
The Technics are rated at 40Hz - 22,000Hz 16 dB below average. Which means that as they play lower bass, the output at a given frequency starts to fall off. 40Hz would be the point at 16dB below the average of all the other higher frequencies. This is about half as loud compared to the rest of the frequencies the speaker is playing. *If* these were spec'd using a +/- 3dB tolerance, the rating might be somthing like 55Hz - 18,000.
The +/- dB reference is basically the window of tolerance for how well the speaker can play all frequencies within the range at the same volume level. Idealy, you want a linear response thru the entire range. The Axioms do very well with this at +/- 3dB. +/- 2dB would be better, and the Technics are not so good at something like +?/-16 dB.
I hope this helps