Group delay in subwoofers

I would think connection via the speaker terminals should have no issue with delay, but I am not an EE.
Perhaps Almarg will help. If anyone knows about this stuff, it's him.
Bob

Delay is caused by the velocity factor of electricity through the paths it takes. Wire and circuit board traces are generally the fastest parts on the trip, but still you need to take the aggregate length of both routes to know if one is significantly delayed compared to the other. This is easily done with an oscilloscope comparing the output of each path fed by the same input source (i.e. a 1khz sine wave). The best solution is to eliminate the subwoofer altogether and go with speakers that have sufficient bottom end response. 

Um, um, um, it is complicated.

By themselves, a large woofer driver does not have any group delay other than the position of the motor relative to the other motors.

BUT!!

DSP processing like you find in a lot of advanced subs can add up to a couple of milliseconds worth of delay. This affects the slope and phase matching as it hands off to the main speakers. On the other hand, if both your top and low are going through DSP, the difference is negligible.

Best,
E

Thanks for the comments.  I had a feeling that it wasn't quite as simple as I had hoped.

JC: Group delay for subs isn't as important as the proper phase/amplitute matching through the crossover, room acoustics and EQ.

That's where you should focus your time and energy.