Like just about any audio equipment assessment, the answer to what makes a perfect woofer diameter is: "it depends".
6.5 vs 8 vs 10 woofer
IMHO I think the 8 is the ideal size cone for mid/small sized listening rooms. Even for large size listening rooms.
The lower mid hz's seem cleaner/clearer. And there is so little fq's in 905+ of the music we listen to, it seems to me the 8 driver is the most perfect size cone.
A 10 size cone has the potential to become overwheling, aggressive, attacking when amp gain is pushed just a tad too much, = Better volume control with a 8 vs a 10.
The 6.5 misses some of that lower bass which a 8 can voice superior.
After listening to several YT vids with a 10 FR, I had considered going 10, but i think staying with a 8 avoids regrets.
I listen at low/mid volume.
The lower mid hz's seem cleaner/clearer. And there is so little fq's in 905+ of the music we listen to, it seems to me the 8 driver is the most perfect size cone.
A 10 size cone has the potential to become overwheling, aggressive, attacking when amp gain is pushed just a tad too much, = Better volume control with a 8 vs a 10.
The 6.5 misses some of that lower bass which a 8 can voice superior.
After listening to several YT vids with a 10 FR, I had considered going 10, but i think staying with a 8 avoids regrets.
I listen at low/mid volume.