A small midrange driver has the advantage of better
transient and speed and probably because of that,
has better clarity. It is also easier to cross to
the tweeter because it has a wide dispersion at around
3khz which is the typical cross over point to the tweeter
for most speakers. The disadvantage of a small midrange
driver is it lacks lower midrange weight vs. say a
5.5in. midrange driver. You could neutralize that
by crossing a small mid range driver to the bass driver
at a higher frequency. For example, a typical 5.5in
midrange driver crosses to the bass driver at around
300 to 400hz. For the small mid range driver of the CS2.4,
you have to cross higher, and I believe from Stereophile
measuremnt page, the CS2.4 cross over point is around 1KHz
between the mid and the bass driver.
The weakness of a larger mid range driver, such as the
5.5in is that at 3khz, it starts beaming so its dispersion
is different from the tweeter so the listening window
is a bit narrower, but it can be done. You could cross
over a 5.5in to the tweeter at a lower freq. maybe around
2.5khz or 2.0khz to improve dispersion but crossing the
tweeter low has its own problem too. I guess it's
a matter of compromise. One is better at higher freq.
and the other is better at the lower freq. One is clearer
and cleaner, whereas the other is a bit warmer and fuller
at the lower midrange freq. I guess it depends on your
preference.
Regardless of how the cross over points are implemented,
ultimately the physics of the size will dictate the sound.
I think that's why many people have said the CS2.4
can sound a bit lean. I don't think in the absolute sense,
they sound lean, but in relative to other speakers that
use larger mid range driver, they do sound a bit lean
relatively. That does not mean they sound bright by
any mean.
