Hi and welcome,
Lots of good advice given by others, but just to update you a little, NAD's "soft-clipping" circuit has been a feature for years of NAD amplifiers. What it does is, at the expense of slightly increased overall distortion (measurable but likely inaudible), it prevents the "hard" and nasty-sounding waveform clipping of conventional solid-state amps driven past their limits. I'd leave soft clipping turned off if I were you.
One poster suggests that the possible 4-ohm load of the Cantons combined with the 4-ohm M80s may be a bit too much for the NAD, and I'd agree.
In the past, Canton speakers had a very "Germanic" sound typical of lots of German brands---a somewhat pumped-up boomy bass, recessed midrange and greatly exaggerated upper highs--cymbals, etc. We used to call it "boom and tizz".
The Axiom M80s are more "linear", better balanced through deep bass, midrange and highs. That will make them sound quite different from your Cantons if the Cantons still have the German voicing.
And for sure try some good movie soundtracks and CDs. MP3 stuff at 128 kbps played over linear speakers like the M80s will reveal any audible defects. Use 320 kbps or higher files to preserve transparency and avoid harshness.
Thank you for your response! I've been reading lots of info on internet and your name comes up a lot. It's great; that you took your time to advise me on the particulars. I will switch the "soft clip" to off and use a good quality recording.
Maybe, I'll purchase the QS8 speakers for surrounds and put my Canton's up for sale.
Maybe, I should upgrade my A/V?
BTW here's the spec's for the canton's;just incase my AV can handle the Cantons.(NAD T765HD) Not too savy when it come AV stuff.
Type Floorstanding speaker
Engineering Principle 2½-way Bass reflex system
Nom. /Music power handling 110 / 170 watts
SPL (1 watt/1m) 87.5 db (1 W, 1 m)
Frequency response 25...40.000 Hz
Crossover frequency 300 / 3.000 Hz
Woofer 1 x 180 mm (7''), Aluminum (Wave surround)
Midrange 1 x 180 mm (7''), Aluminum (Wave surround)
Tweeter 1 x 25 mm (1''), aluminum-manganese
Nominal Impedance 4...8 ohms
Dimensions (WxHxD) 19 x 95 x 29 cm
(7.5'' x 37.4'' x 11.4'')
Weight 16.3 kg