Axiomman,
It isn't the use of the two tweeters or dual midranges in the original M80ti (around 2002, when I joined Axiom) that gave it a midrange/upper midrange aggressiveness that I didn't care for; it was a glitch--in techie terms, a non-linearity--in the frequency response that gave it an edginess noticeable on vocals, brasses and other instruments with upper midrange content. The dual midrange drivers and dual tweeters were added years ago by Ian to raise the power handling of the M80s and enable them to play very, very loud and clean, if listeners wanted those high SPLs in playback.
The resistors we briefly handed out to M80ti owners who complained of the edginess were a temporary and not very successful "fix", until Ian Colquhoun re-designed the crossover around Fall of 2003. The new "ti" M80 was much smoother and more linear, and it no longer had the upper midrange "edge" that I objected to in the blind listening tests of the original M80ti. However, the actual model number of the M80ti did not change until 2005, when the v2 series was introduced, along with other cosmetic/mechanical differences.
The M80 v3 included cosmetic and some minor mechanical changes but the biggest difference was the new titanium dome tweeter(s), with smoother and more linear off-axis response. In double-blind listening tests, this resulted in a more spacious and broader soundstage and smoother response overall. Those benefits of the v3 tweeter also extended to other Axiom models, including the M22 v3s, which I auditioned at great length against my old M22ti's.
Each evolution of the M80 has brought audible improvements, and these also trickled down to the M60 v3 and M22 v3.
Regards,
Alan
