[collo]

The extra output of a ported system comes from exciting a resonance over the working range of the port.

I've always suspected that such a system may take several cycles to build to full excitation, and possibly delay over several cycles. If so, this may lead to sharp transients being less well reproduced in a ported system.

I was interested to see if there was any evidence of this happening in Rodny's ported IB.


I used the term "group delay" as this is visible in WinISD when you compare ported vs sealed. I think it actually emcompasses more than just the phenomenon I described, and I'm not sure how one would measure it.

I certainly don't see this as greatly diminishing the benefits of a ported sub (I've built a few...), but opportunities for an A-B test don't come along very often.