I have not started to build 2Pi yet, because i am hesitating to
start may be with a dessign offering more bass.

I can't find any comments/recommendation of Beta-15 speaker in 4Pi.
Is there some reason I ignore ?
After last change of Eminence parameters, it seems that Beta-15
is quiet good replacement for oldest Aplha-15: require the similar box
dimensions and offer the similar bass response
(Beta-15 in 7cu ft has -3dB at 44Hz, Alpha-15 -oldestt- had
-3dB at 42Hz in 8 cu ft).
This is nearest than new Alpha-15 which require 11.5 cu ft.

Is there some sonic penalty for Beta-15 ?

Thanks in advance,
O'Tor.

Thanks for your response. I would also like to ask you if the
midrange quality of Alpha-based one and two Pi is the same.
I.e. the only change for the passing from one Pi to two Pi is
the benefit of deeper bass ?
I am asking this because in the hifi-line, there is often some
midrange degradation for the largest cones, especially when they
are used with no low-pass crossover (often a huge peaks and
irregularities in the 3-5kHz region, and often not shown on the
driver SPL plot but still audible).

TIA,
O'Tor