[Doublej]

In layman's term can someone explain what group delay is? My understanding is that it does not exist in a sealed design. Does it matter if a system with a subwoofer has mains that are ported and a subwoofer that is sealed or vice versa?

[JohnR]

It's basically a delay of the signal that varies with frequency. Sealed subs have group delay, but less than ported (speaking in generalities and assumptions). From your second question it sounds like the question is really about bass integration? I've found that matching slopes (and time delays) usually gets me most of the way there. The group delay curve will be different for the two scenarios.

Why do you ask?

[Doublej]

Very simply I am trying to understand if there would be any issues with purchasing a small sealed subwoofer such as the PSB Sub Series 100 to provide more bottom end to my Hsu HB-1s.

[JohnR]

Hi again, I'd be more concerned about a. output level and b. integration (crossover, slope and frequency adjustment).