Definition of "transient performance" of a speaker

ctviggen · « **on:** 11 Jan 2006, 01:03 pm »

I'm reading "The Loud Speaker Design Cookbook" by Vance Dickason. When discussing vented box low frequency systems, he creates a table of of alignment types. When discussing the various alignments, he states the following: "The difference lies in the somewhat better transient performance reflected in the slightly more shallow rolloff of the SBB4 alignment." The table lists a rolloff of 18 db/octave slope for the SBB4 (as opposed to higher rolloffs of 19, 20, 27, and 30 db/oct).

What does rolloff have to do with transient performance?

_scotty_ · « **Reply #1 on:** 11 Jan 2006, 08:12 pm »

The rolloff has nothing to do with the transient behavior per se.
The rolloff rate is a product of the Q of the alignment which determines the transient behavior of the system.
Scotty

ctviggen · « **Reply #2 on:** 11 Jan 2006, 08:36 pm »

Thanks, Scotty.

_scotty_ · « **Reply #3 on:** 11 Jan 2006, 09:09 pm »

ctviggen,you might check Vance's footnotes for further reading on this subject. This article from JAES might also prove interesting.
http://www.aes.org/e-lib/browse.cfm?elib=5799
Scotty