Group Delay and Delay


2010-07-28 10:47 am
A "simple" question but I am guessing not a simple answer?!

I understand any driver mounted in a defined box type has its own GD curve, plotted by many simple software design packages.

Using WinISDpro you can simulate a filter and it will show the combined GD of driver and filter. Its easy to read the GD off the plots against frequency.

Here's the question. If you are going to add "global" delay from a DSP is it just as simple as deriving the GD from the driver/filter plot at any one frequency and adding the delay from the DSP. Say you have a GD of .3ms at a particular frequency from the driver/filter combination and you add .5ms of DSP delay does that = .8ms total at that frequency??

I ask because I am working on a column speaker with gain shading and different delays to the drivers from DSP and not sure if I should just add in the GD from the driver/filter at each chosen frequency point to create the polar plot.