sorry to say guys, but i think this is all bollocks.
Canton has their way of defining specs since the early 70s and never changed AFAIK
. It was always a purely electrical spec - a technical rating referring to the crossover design, not audible capabilities. 20Hz... was always cut off freq, no -dB anything, no indicator for roll off. And when all other manufactures put the upper end way beyond 20kHz they followed suit. Listening at 40kHz anybody?
And while in metric world - where they come from - they provide exact dimensions of chassis in the imperial inch world they just provide rough guidance for buyers who are used to inches. It's obvious when looking at the specs. It's not a big issue either, coz freq reproduction is not solely defined by the diameter.
Everything about certain user expectations on what a specific rating should stand for just developed in the last two decades when our homies got more and more into building home theaters and started debating on the Internet. The hifi world is full of flawed specs made by marketing ppl. You can only really compare at single digits within same brand, and even then you might be mislead. Its a mess but it is what it is.
I'd definitely prefer Canton keeps rating speakers as they do. The only thing they could improve on is a SPL diagram in detailed spec sheet, but that's a twofold thing, most ppl make wrong conclusions on those. Very few manufacturers do such diagrams
, there is no international normative standard to make those either.
I think in the end it's all good, you get what you pay for. And if you're serious about it you better test listen before, going only by written specs does not tell how good a speaker really sounds.