If loudspeakers could somehow magically occupy the same point in space, our work would be considerably less difficult. Unfortunately, actual, physical loudspeaker enclosures prohibit us from doing so, which is when "Shit hits the fans" (plural). Physical displacement between multiple loudspeakers is one of the prime challenges in sound system design.
figure 1One of the biggest challenges every new generation of sound engineers appears to struggle with is learning how to phase align subwoofers to mains. A quest which at one point in my early career felt like impossible.
In this article, I will disclose the method which has been working flawlessly for me in the past couple of years. It's a two-step process consisting of a relative and absolute part.
If you lookup group delay on Wikipedia, you'll find the following definition:
"Group delay is the time delay of the amplitude envelopes of the various sinusoidal components of a signal through a device under test (DUT)."
Where various can be thought of as assorted or mixed.
The first time I read that, my initial thought was: "Come again?". I mean seriously, what does that even mean?
During the past three years, this long-dreaded article has been slowly taking shape in my mind. Finally, I have found the courage to write it because frankly, I don't know if I even understand it myself. So here goes nothing.